1. |
- Karlsson, Maria, 1985, et al.
(författare)
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Reconstitution of water channel function of an aquaporin overexpressed and purified from Pichia pastoris.
- 2003
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Ingår i: FEBS Letters. - 1873-3468 .- 0014-5793. ; 537:1-3, s. 68-72
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Tidskriftsartikel (refereegranskat)abstract
- The aquaporin PM28A is one of the major integral proteins in spinach leaf plasma membranes. Phosphorylation/dephosphorylation of Ser274 at the C-terminus and of Ser115 in the first cytoplasmic loop has been shown to regulate the water channel activity of PM28A when expressed in Xenopus oocytes. To understand the mechanisms of the phosphorylation-mediated gating of the channel the structure of PM28A is required. In a first step we have used the methylotrophic yeast Pichia pastoris for expression of the pm28a gene. The expressed protein has a molecular mass of 32462 Da as determined by matrix-assisted laser desorption ionization-mass spectrometry, forms tetramers as revealed by electron microscopy and is functionally active when reconstituted in proteoliposomes. PM28A was efficiently solubilized from urea- and alkali-stripped Pichia membranes by octyl-beta-D-thioglucopyranoside resulting in a final yield of 25 mg of purified protein per liter of cell culture.
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2. |
- Persson, Daniel, 1972, et al.
(författare)
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Penetratin-induced Aggregation and Subsequent Dissociation of Negatively Charged Phospholipid Vesicles
- 2001
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Ingår i: FEBS Letters. - 1873-3468 .- 0014-5793. ; 505:2, s. 307-312
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Tidskriftsartikel (refereegranskat)abstract
- The interaction of the cellular delivery vector penetratin with a model system consisting of negatively charged phospholipid vesicles has been studied. Above a certain peptide to lipid molar ratio, the cationic oligopeptide induces vesicle aggregation. Interestingly, the aggregation is followed by spontaneous disaggregation, which may be related to membrane translocation of the peptide. Circular dichroism (CD) measurements indicate a conformational transition, from alpha -helix to antiparallel beta -pleated sheet, which is simultaneous with the aggregation process. The potential influence of spectroscopic artifacts on CD data due to the drastically increased turbidity during aggregation is discussed.
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3. |
- Thoren, Per, 1972, et al.
(författare)
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The Antennapedia peptide penetratin translocates across lipid bilayers - the first direct observation
- 2000
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Ingår i: FEBS Letters. - 1873-3468 .- 0014-5793. ; 482:3, s. 265-268
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Tidskriftsartikel (refereegranskat)abstract
- The potential use of polypeptides and oligonucleotides for therapeutical purposes has been questioned because of their inherently poor cellular uptake. However, the 16-mer oligopeptide penetratin, derived from the homeodomain of Antennapedia, has been reported to enter cells readily via a non-endocytotic and receptor- and transporter-independent pathway, even when conjugated to large hydrophilic molecules. We here present the first study where penetratin is shown to traverse a pure lipid bilayer. The results support the idea that the uptake mechanism involves only the interaction of the peptide with the membrane lipids. Furthermore, we conclude that the translocation does not involve pore formation.
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4. |
- Chang, Shu-Nu, 1975-, et al.
(författare)
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An acidic amino acid cluster regulates the nucleolar localization and ribosome assembly of human ribosomal protein L22
- 2000
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Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 484:1, s. 22-28
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Tidskriftsartikel (refereegranskat)abstract
- The control of human ribosomal protein L22 (rpL22) to enter into the nucleolus and its ability to be assembled into the ribosome is regulated by its sequence. The nuclear import of rpL22 depends on a classical nuclear localization signal of four lysines at positions 13-16. RpL22 normally enters the nucleolus via a compulsory sequence of KKYLKK (I-domain, positions 88-93). An acidic residue cluster at the C-terminal end (C-domain) plays a nuclear retention role. The retention is concealed by the N-domain (positions 1-9) which weakly interacts with the C-domain as demonstrated in the yeast two-hybrid system. Once it reaches the nucleolus, the question of whether rpL22 is assembled into the ribosome depends upon the presence of the N-domain. This suggests that the N-domain, on dissociation from its interaction with the C-domain, binds to a specific region of the 28S rRNA for ribosome assembly.
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5. |
- Jonsson, AP, et al.
(författare)
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A novel Ser O-glucuronidation in acidic proline-rich proteins identified by tandem mass spectrometry.
- 2000
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Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 475:2, s. 131-4
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Tidskriftsartikel (refereegranskat)abstract
- Human acidic proline-rich salivary protein PRP-1 and its C-terminally truncated form PRP-3 were analyzed by electrospray tandem mass spectrometry. Post-translational modifications were detected and characterized. A pyroglutamic acid residue was demonstrated at the N-terminus, Ser-8 and Ser-22 were shown to be phosphorylated and an O-linked glucuronic acid conjugation was identified. The latter modification was located to Ser-17 and found to be present in approximately 40% of the polypeptides.
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6. |
- Alam, M.T., et al.
(författare)
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The importance of being knotted : Effects of the C-terminal knot structure on enzymatic and mechanical properties of bovine carbonic anhydrase II1
- 2002
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 519:1-3, s. 35-40
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Tidskriftsartikel (refereegranskat)abstract
- In order to better understand the contribution of the knotted folding pattern to the enzymatic and mechanical properties of carbonic anhydrases, we replaced Gln-253 of bovine carbonic anhydrase II with Cys, which allowed us to measure the mechanical strength of the protein against tensile deformation by avoiding knot tightening. The expressed protein, to our surprise, turned out to contain two conformational isomers, one capable of binding an enzymatic inhibitor and the other not, which led to their separation through affinity chromatography. In near- and far-UV circular dichroism and fluorescence spectra, the separated conformers were very similar to each other and to the wild-type enzyme, indicating that they both had native-like conformations. We describe new evidence which supports the notion that the difference between the two conformers is likely to be related to the completeness of the C-terminal knot formation. © 2002 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.
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7. |
- Alleva, R., et al.
(författare)
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Coenzyme Q blocks biochemical but not receptor-mediated apoptosis by increasing mitochondrial antioxidant protection
- 2001
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 503:1, s. 46-50
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Tidskriftsartikel (refereegranskat)abstract
- Generation of free radicals is often associated with the induction and progression of apoptosis. Therefore, antioxidants can prove anti-apoptotic, and can help to elucidate specific apoptotic pathways. Here we studied whether coenzyme Q, present in membranes in reduced (ubiquinol) or oxidised (ubiquinone) forms, can affect apoptosis induced by various stimuli. Exposure of Jurkat cells to a-tocopheryl succinate (a-TOS), hydrogen peroxide, anti-Fas IgM or TRAIL led to induction of apoptosis. Cell death due to the chemical agents was suppressed in cells enriched with the reduced form of coenzyme Q. However, coenzyme Q did not block cell death induced by the immunological agents. Ubiquinol-10 inhibited reactive oxygen species (ROS) generation in cells exposed to a-TOS, and a mitochondrially targeted coenzyme Q analogue also blocked apoptosis triggered by a-TOS or hydrogen peroxide. Therefore, it is plausible that ubiquinol-10 protects cells from chemically-induced apoptosis by acting as an antioxidant in mitochondria. Our results also indicate that generation of free radicals may not be a critical step in induction of apoptosis by immunological agents. © 2001 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.
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8. |
- Basu, Samar, et al.
(författare)
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Biomarkers of free radical injury during spinal cord ischemia
- 2001
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 508:1, s. 36-38
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Tidskriftsartikel (refereegranskat)abstract
- Plasma and urinary levels of 8-iso-PGF(2alpha) and 15-keto-dihydro-PGF(2alpha) were analysed at baseline and during the ischemia-reperfusion period in experimental spinal cord ischemia. A significant and immediate increase of 8-iso-PGF(2alpha) in plasma at the start and up to 60 min, and in the urine at 90-150 min following ischemia indicate an association of oxidative injury. The inflammatory response indicator 15-keto-dihydro-PGF(2alpha) in plasma increased significantly at the start and up to 60 min after ischemia. No such increase was seen in animals with no spinal cord ischemia. Thus, free radical mediated and cyclooxygenase catalysed products of arachidonic acid are increased during spinal cord ischemia as a consequence of oxidative injury and inflammation.
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9. |
- Basu, Samar, et al.
(författare)
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Development of a novel biomarker of free radical damage in reperfusion injury after cardiac arrest
- 2000
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 470:1, s. 1-6
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Tidskriftsartikel (refereegranskat)abstract
- In a porcine model of cardiopulmonary resuscitation (CPR), we investigated changes in the plasma levels of 8-iso-PGF(2alpha), a marker for oxidative injury, and 15-keto-dihydro-PGF(2alpha), an inflammatory response indicator during the post-resuscitation period after cardiac arrest. Twelve piglets were subjected to either 2 or 5 min (VF2 and VF5 group) of ventricular fibrillation (VF) followed by 5 min of closed-chest CPR. Six piglets without cardiac arrest were used as controls. In VF5 group, 8-iso-PGF(2alpha) in the jugular bulb plasma (draining the brain) increased four-fold. Jugular bulb 8-iso-PGF(2alpha) in the control group remained unchanged. The 15-keto-dihydro-PGF(2alpha) also increased four-fold in the VF5 group. Thus, 8-iso-PGF(2alpha) and 15-keto-dihydro-PGF(2alpha) measurements in jugular bulb plasma may be used as biomarkers for quantification of free radical catalyzed oxidative brain injury and inflammatory response in reperfusion injury
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10. |
- Bu, Shizhong, et al.
(författare)
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Mechanisms for 2-methoxyestradiol-induced apoptosis of prostate cancer cells
- 2002
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 531:2, s. 141-51
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Tidskriftsartikel (refereegranskat)abstract
- Prostate and breast carcinomas are sex hormone-related carcinomas, which are known to be associated with an over-expression of the proto-oncogene Bcl-2. Here, we report that 2-methoxyestradiol (2-ME), an endogenous metabolite of estrogen that does not bind to nuclear estrogen receptors, effectively induces apoptosis in Bcl-2-expressing human prostate and breast carcinoma cells in vitro and in a rat prostate tumor model in vivo. In several cell lines derived from prostate, breast, liver and colorectal carcinomas, 2-ME treatment led to an activation of c-Jun N-terminal kinase (JNK) and phosphorylation of Bcl-2, which preceded the induction of apoptosis. In summary, our data suggest that 2-ME induces apoptosis in epithelial carcinomas by causing phosphorylation of JNK, which appears to be correlated with phosphorylation of Bcl-2.
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11. |
- Chang, Shu-Nu, 1975-, et al.
(författare)
-
An acidic amino acid cluster regulates the nucleolar localization and ribosome assembly of human ribosomal protein L22
- 2000
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 484:1, s. 22-28
-
Tidskriftsartikel (refereegranskat)abstract
- The control of human ribosomal protein L22 (rpL22) to enter into the nucleolus and its ability to be assembled into the ribosome is regulated by its sequence. The nuclear import of rpL22 depends on a classical nuclear localization signal of four lysines at positions 13-16. RpL22 normally enters the nucleolus via a compulsory sequence of KKYLKK (I-domain, positions 88-93). An acidic residue cluster at the C-terminal end (C-domain) plays a nuclear retention role. The retention is concealed by the N-domain (positions 1-9) which weakly interacts with the C-domain as demonstrated in the yeast two-hybrid system. Once it reaches the nucleolus, the question of whether rpL22 is assembled into the ribosome depends upon the presence of the N-domain. This suggests that the N-domain, on dissociation from its interaction with the C-domain, binds to a specific region of the 28S rRNA for ribosome assembly.
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12. |
- Chumnarnsilpa, Sakesit, 1967-, et al.
(författare)
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Activation in isolation : exposure of the actin-binding site in the C-terminal half of gelsolin does not require actin
- 2003
-
Ingår i: FEBS Letters. - Netherlands : Elsevier Science B.V.. - 0014-5793 .- 1873-3468. ; 552:2-3, s. 82-85
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Tidskriftsartikel (refereegranskat)abstract
- Gelsolin requires activation to carry out its severing and capping activities on F-actin. Here, we present the structure of the isolated C-terminal half of gelsolin (G4-G6) at 2.0 A resolution in the presence of Ca(2+) ions. This structure completes a triptych of the states of activation of G4-G6 that illuminates its role in the function of gelsolin. Activated G4-G6 displays an open conformation, with the actin-binding site on G4 fully exposed and all three type-2 Ca(2+) sites occupied. Neither actin nor the type-l Ca(2+), which normally is sandwiched between actin and G4, is required to achieve this conformation.
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13. |
- Fredriksson, Robert, et al.
(författare)
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Novel human G protein-coupled receptors with long N-terminals containing GPS domains and Ser/Thr-rich regions
- 2002
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 531:3, s. 407-414
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Tidskriftsartikel (refereegranskat)abstract
- We report eight novel members of the superfamily of human G protein-coupled receptors (GPCRs) found by searches in the human genome databases, termed GPR97, GPR110, GPR111, GPR112, GPR113, GPR114, GPR115 and GPR116. Phylogenetic analysis shows that these are additional members of a family of GPCRs with long N-termini, previously termed EGF-7TM, LNB-7TM, B2 or LN-7TM. Five of the receptors form their own phylogenetic cluster, while three others form a cluster with the previously reported HE6 and GPR56 (TM7XN1). All the receptors have a GPS domain in their N-terminus and long Ser/Thr-rich regions forming mucin-like stalks. GPR113 has a hormone binding domain and one EGF domain. GPR112 has over 20 Ser/Thr repeats and a pentraxin domain. GPR116 has two immunoglobulin-like repeats and a SEA box. We found several human EST sequences for most of the receptors showing differential expression patterns, which may indicate that some of these receptors participate in reproductive functions while others are more likely to have a role in the immune system.
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14. |
- Funk, Christiane, et al.
(författare)
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D1' centers are less efficient than normal photosystem II centers
- 2001
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 505:1, s. 113-117
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Tidskriftsartikel (refereegranskat)abstract
- One prominent difference between the photosystem II (PSII) reaction center protein D1 ' in Synechocystis 6803 and normal D1 is the replacement of Phe-186 in D1 with leucine in D1 '. Mutants of Synechocystis 6803 producing only D1 ', or containing engineered D1 proteins with Phe-186 substitutions, were analyzed by 77 K fluorescence emission spectra, chlorophyll a fluorescence induction yield and decay kinetics, and flash-induced oxygen evolution. Compared to D1-containing PSII centers, D1 ' centers exhibited a 50% reduction in variable chlorophyll a fluorescence yield, while the flash-induced O-2 evolution pattern was unaffected. In the F186 mutants, both the P680(+)/Q(A)(-) recombination and O-2 oscillation pattern were noticeably perturbed.
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15. |
- Grimm, T, et al.
(författare)
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Genomic organization and embryonic expression of Suppressor of Fused, a candidate gene for the split-hand/split-foot malformation type 3
- 2001
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 505:1, s. 13-17
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Tidskriftsartikel (refereegranskat)abstract
- The genes for human and mouse Suppressor of Fused (SU(FU)/Su(Fu)) in the Hedgehog signaling pathway were characterized and found to contain 12 exons. Human SU(FU) localized on chromosome 10q24-25 between the markers D10S192 and AFM183XB12. We detected three additional SU(FU) isoforms, two of which have lost their ability to interact with the transcription factor GLI1. Expression analysis using whole mount in situ hybridization revealed strong expression of Su(Fu) in various mouse embryonic tissues. SU(FU) was considered a candidate gene for the split-hand/split-foot malformation type 3 (SHFM3). However, no alterations in the SU(FU) gene were found in SHFM3 patients.
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16. |
- Hilden, L., et al.
(författare)
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Do the extracellular enzymes cellobiose dehydrogenase and manganese peroxidase form a pathway in lignin biodegradation?
- 2000
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 477:02-jan, s. 79-83
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Tidskriftsartikel (refereegranskat)abstract
- The extracellular enzyme manganese peroxidase is believed to degrade lignin by a hydrogen peroxide-dependent oxidation of Mn(II) to the reactive species Mn(III) that attacks the lignin, However, Mn(III) is not able to directly oxidise the non-phenolic lignin structures that predominate in native lignin, We show here that pretreatment of a non-phenolic lignin model compound with another extracellular fungal enzyme, cellobiose dehydrogenase, allows the manganese peroxidase system to oxidise this molecule. The mechanism behind this effect is demethoxylation and/or hydroxylation, i.e. conversion of a nonphenolic structure to a phenolic one, mediated by hydroxyl radicals generated by cellobiose dehydrogenase, This suggests that cellobiose dehydrogenase and manganese peroxidase may act in an extracellular pathway in fungal lignin biodegradation, Analytical techniques used in this paper are reverse-phase high-pressure liquid chromatography, gas chromatography connected to mass spectroscopy and UV-visible spectroscopy.
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17. |
- Jimenez, A, et al.
(författare)
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Human spermatid-specific thioredoxin-1 (Sptrx-1) is a two-domain protein with oxidizing activity
- 2002
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 530:1-3, s. 79-84
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Tidskriftsartikel (refereegranskat)abstract
- Spermatid-specific thioredoxin-1 (Sptrx-1) is the first member of the thioredoxin family of proteins with a tissue-specific expression pattern, found exclusively in the tail of elongating spermatids and spermatozoa. We describe here further biochemical characterization of human Sptrx-1 protein structure and enzymatic activity. In gel filtration chromatography human Sptrx-1 eluates as a 400 kDa protein consistent with either an oligomeric form, not maintained by intermolecular disulfide bonding, and/or a highly asymmetrical structure. Analysis of circular dichroism spectra of fragments 1-360 and 361-469 and comparison to spectra of full-length Sptrx-1 supports a two-domain organization with a largely unstructured N-terminal domain and a folded thioredoxin-like C-terminal domain. Functionally, Sptrx-1 behaves as an oxidant in vitro when using selenite, but not oxidized glutathione, as electron acceptor. This oxidizing enzymatic activity suggests that Sptrx-1 might govern the stabilization (by disulfide cross-linking) of the different structures in the developing tail of spermatids and spermatozoa.
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18. |
- Kaarniranta, Kai, et al.
(författare)
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Protein synthesis is required for stabilization of hsp70 mRNA upon exposure to both hydrostatic pressurization and elevated temperature.
- 2000
-
Ingår i: FEBS Letters. - : Elsevier. - 0014-5793 .- 1873-3468. ; 475:3, s. 283-286
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Tidskriftsartikel (refereegranskat)abstract
- We have recently described that in chondrocytic cells high hydrostatic pressure (HP) causes a heat shock response via mRNA stabilization without a transcriptional activation of the hsp70 gene. In this study, we investigated whether this exceptional regulatory mechanism occurs more generally in different types of cells. Indeed, hsp70 mRNA and protein accumulated in HeLa, HaCat and MG-63 cells under 30 MPa HP, without DNA-binding of heat shock transcription factor 1 (HSF1) to the heat shock element of the hsp70 gene or formation of nuclear HSF1 granules, revealing a lack of transcriptional activation. Moreover, we observed that protein synthesis is needed for mRNA stabilization. Thus, high HP offers a model to study the mechanisms of hsp70 mRNA stabilization without HSF1-mediated induction of the heat shock gene response.
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19. |
- Kieselbach, T, et al.
(författare)
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A peroxidase homologue and novel plastocyanin located by proteomics to the Arabidopsis chloroplast thylakoid lumen
- 2000
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 480:2-3, s. 271-276
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Tidskriftsartikel (refereegranskat)abstract
- A study by two-dimensional electrophoresis showed that the soluble, lumenal fraction of Arabidopsis thaliana thylakoids can be resolved into 300 protein spots. After subtraction of low-intensity spots and accounting for low-level stromal contamination, the number of more abundant, lumenal proteins was estimated to be between 30 and 60. Two of these proteins have been identified: a novel plastocyanin that also was the predominant component of the total plastocyanin pool, and a putative ascorbate peroxidase. Import studies shamed that these proteins are routed to the thylakoid lumen by the Sec- and delta pH-dependent translocation pathways, respectively, In addition, novel isoforms of PsbO and PsbQ were identified.
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20. |
- Käll, Lukas, 1969-, et al.
(författare)
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Reliability of transmembrane predictions in whole-genome data
- 2002
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 532:3, s. 415-418
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Tidskriftsartikel (refereegranskat)abstract
- Transmembrane prediction methods are generally benchmarked on a set of proteins with experimentally verified topology. We have investigated if the accuracy measured on such datasets can be expected in an unbiased genomic analysis, or if there is a bias towards 'easily predictable' proteins in the benchmark datasets. As a measurement of accuracy, the concordance of the results from five different prediction methods was used (TMHMM, PHD, HMMTOP, MEMSAT, and TOPPRED). The benchmark dataset showed significantly higher levels (up to five times) of agreement between different methods than in 10 tested genomes. We have also analyzed which programs are most prone to make mispredictions by measuring the frequency of one-out-of-five disagreeing predictions.
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21. |
- Li, Wei, 1962-, et al.
(författare)
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Induction of cell death by the lysosomotropic detergent MSDH
- 2000
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 470:1, s. 35-39
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Tidskriftsartikel (refereegranskat)abstract
- Controlled lysosomal rupture was initiated in lysosome-rich, macrophage-like cells by the synthetic lysosomotropic detergent, O-methyl-serine dodecylamide hydrochloride (MSDH). When MSDH was applied at low concentrations, resulting in partial lysosomal rupture, activation of pro-caspase-3-like proteases and apoptosis followed after some hours. Early during apoptosis, but clearly secondary to lysosomal destabilization, the mitochondrial transmembrane potential declined. At high concentrations, MSDH caused extensive lysosomal rupture and necrosis. It is suggested that lysosomal proteases, if released to the cytosol, may cause apoptosis directly by pro-caspase activation and/or indirectly by mitochondrial attack with ensuing discharge of pro-apoptotic factors.
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22. |
- McGee, Karen, et al.
(författare)
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Microtubule-dependent regulation of Rho GTPases during internalisation of Yersinia pseudotuberculosis
- 2003
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 533:1-3, s. 35-41
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Tidskriftsartikel (refereegranskat)abstract
- Internalisation of the human pathogen Yersinia pseudotuberculosis via interaction of bacterial invasin with host beta1 integrins depends on the actin cytoskeleton and involves Src family kinases, focal adhesion kinase, p130Crk-associated substrate, proline-rich tyrosine kinase 2, Rac, Arp 2/3 complex and WASP family members. We show here that Rho GTPases are regulated by the microtubule system during bacterial uptake. Interfering with microtubule organisation using nocodazole or paclitaxel suppressed uptake by HeLa cells. The nocodazole effect on microtubule depolymerisation was partially inhibited through overexpression of Rac, Cdc42, RhoG or RhoA and completely prevented by expression of Vav2. This suggests that microtubules influence Rho GTPases during invasin-mediated phagocytosis and in the absence of functional microtubules Vav2 can mimic their effect on one, or more, of the Rho family GTPases. Lastly, overexpression of p50 dynamitin partially inhibited bacterial uptake and this effect was also blocked by co-expression of Vav2, thus further implicating this guanine nucleotide exchange factor in activating Rho GTPases for internalisation during loss of microtubule function.
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23. |
- Nilsson, IngMarie, et al.
(författare)
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Cleavage of a tail-anchored protein by signal peptidase
- 2002
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 516:1-3, s. 106-108
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Tidskriftsartikel (refereegranskat)abstract
- Tail-anchored proteins are post-translationally targeted and inserted into the endoplasmic reticulum membrane. They do not use the co-translational sign at-recognition particle (SRP)-dependent pathway, but rather utilize an ill-defined, ATP-dependent mechanism. Here, we show that a tail-anchored protein can be cleaved by signal peptidase and that the sequence requirements for efficient cleavage seem to be the same as for cleavage of co-translationally targeted SRP-dependent proteins.
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24. |
- Persson, Camilla, et al.
(författare)
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Primary sequence determinants responsible for site-selective dephosphorylation of the PDGF beta-receptor by the receptor-like protein tyrosine phosphatase DEP-1
- 2002
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 517:1-3, s. 27-31
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Tidskriftsartikel (refereegranskat)abstract
- Site-selective dephosphorylation of receptor tyrosine kinases contributes to receptor regulation. The receptor-like protein tyrosine phosphatase DEP-1 site-selectively dephosphorylates the PDGF beta-receptor. DEP-1 dephosphorylation of original and chimeric phospho-peptides spanning the preferred pY1021 and the less preferred pY857 and pY562 sites was analyzed. Double substitutions of basic residues at -4 and +3 of pY857 and pY562 peptides improved affinity. Substitutions of single amino acids indicated preference for an acidic residue at position -1 and a preference against a basic residue at position +3. DEP-1 site-selective dephosphorylation of PDGF beta-receptor is thus determined by the primary sequence surrounding phosphorylation sites and involves interactions with residues spanning at least between positions -1 and +3.
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25. |
- Punga, Tanel, et al.
(författare)
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Adenovirus 2 E1B-55K protein relieves p53-mediated transcriptional repression of the survivin and MAP4 promoters
- 2003
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 552:2-3, s. 214-218
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Tidskriftsartikel (refereegranskat)abstract
- It is well established that adenovirus E1B-55K protein functions as an inhibitor of the tumor suppressor protein p53 by binding and inactivating p53 as a transcriptional activator protein. Here we show that the adenovirus 2 E1B-55K protein also blocks p53 as a transcriptional repressor protein of the survivin and the MAP4 promoters. The repression is dependent on the ability of E1B-55K to bind to p53 and is enhanced by coexpression of the adenovirus E4orf6 protein. Overexpression of the transcriptional corepressor protein Sin3A partially relieves the inhibitory effect of E1B-55K, suggesting that E1B-55K blocks p53 functions by interfering with the Sin3 complex.
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26. |
- Punga, Tanel, et al.
(författare)
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The adenovirus-2 E1B-55K protein interacts with a mSin3A/histone deacetylase 1 complex
- 2000
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 476:3, s. 248-252
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Tidskriftsartikel (refereegranskat)abstract
- The adenovirus E1B-55K protein is a multifunctional phosphoprotein that regulates nuclear to cytoplasmic export of host cell and viral mRNAs during lytic viral growth. E1B-55K also blocks apoptosis by binding and functionally inactivating the human tumor suppressor protein p53. Here, we show that E1B-55K interacts with histone deacetylase 1 (HDAC1) and the transcriptional corepressor protein mSin3A, both in the adenovirus-transformed 293 cell line and during a lytic adenovirus infection. Furthermore, we show that the central amino acids 156-261 in E1B-55K are necessary for efficient HDAC1 interaction. Importantly, the E1B-55K/mSin3A/HDAC1 complex is also enzymatically active, catalyzing deacetylation of a histone substrate peptide. Collectively, our results suggest that E1B-55K interaction with mSin3A/HDAC1 containing complexes may be significant for one or several of the multiple activities ascribed to this protein.
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27. |
- Surapureddi, Sailesh, et al.
(författare)
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Colocalization of leukotriene C synthase and microsomal glutathione S-transferase elucidated by indirect immunofluorescence analysis
- 2000
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 480:2-3, s. 239-243
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Tidskriftsartikel (refereegranskat)abstract
- We have previously shown that the two membrane bound enzymes leukotriene C synthase and microsomal glutathione S-transferase interact in vitro and in vivo. Rat basophilic leukemia cells and murine mastocytoma cells, two well-known sources of leukotriene C synthase, both expressed microsomal glutathione S-transferase as determined by Western blot analyses. Several human tissues were found to contain both leukotriene C synthase and microsomal glutathione S-transferase mRNA. These data suggest that the interaction may be physiologically important. To study this further, expression vectors encoding the two enzymes were cotransfected into mammalian cells and the subcellular localization of the enzymes was determined by indirect immunofluorescence using confocal laser scanning microscopy. The results showed that leukotriene C synthase and microsomal glutathione S-transferase were both localized on the nuclear envelope and adjacent parts of the endoplasmic reticulum. Image overlay demonstrated virtually identical localization. We also observed that coexpression substantially reduced the catalytic activity of each enzyme suggesting that a mechanism involving protein–protein interaction may contribute to the regulation of LTC4 production.
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28. |
- Thidholm, Ellinor, et al.
(författare)
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Novel approach reveals localisation and assembly pathway of the PsbS and PsbW proteins into the photosystem II dimer
- 2002
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Ingår i: FEBS LETTERS. - 0014-5793 .- 1873-3468. ; 513:2-3, s. 217-22
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Tidskriftsartikel (refereegranskat)abstract
- A blue-native gel electrophoresis system was combined with an in organello import assay to specifically analyse the location and assembly of two nuclear-encoded photosystem 11 (PSII) subunits. With this method we were able to show that initially the low molecular mass PsbW protein is not associated with the monomeric form of PSII. Instead a proportion of newly imported PsbW is directly assembled in dimeric PSH super-complexes with very fast kinetics; its negatively charged N-terminal domain is essential for this process. The chlorophyll-binding PsbS protein, which is involved in energy dissipation, is first detected in the monomeric PSII subcomplexes, and only at later time points in the dimeric form of PSII. It seems to be bound tighter to the PSII core complex than to light harvesting complex II. These data point to radically different assembly pathways for different PSII subunits. (C) 2002 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.
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29. |
- Turkina, Maria V, et al.
(författare)
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The transit peptide of CP29 thylakoid protein in Chlamydomonas reinhardtii is not removed but undergoes acetylation and phosphorylation
- 2004
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Ingår i: FEBS Letters. - Amsterdam : Elsevier. - 0014-5793 .- 1873-3468. ; 564:1-2, s. 104-108
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Tidskriftsartikel (refereegranskat)abstract
- The surface-exposed peptides were cleaved by trypsin from the photosynthetic thylakoid membranes isolated from the green alga Chlamydomonas reinhardtii. Two phosphorylated peptides, enriched from the peptide mixture and sequenced by nanospray quadrupole time-of-flight mass spectrometry, revealed overlapping sequences corresponding to the N-terminus of a nuclear-encoded chlorophyll a/b-binding protein CP29. In contrast to all known nuclear-encoded thylakoid proteins, the transit peptide in the mature algal CP29 was not removed but processed by methionine excision, N-terminal acetylation and phosphorylation on threonine 6. The importance of this phosphorylation site is proposed as the reason of the unique transit peptide retention.
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30. |
- Urban, Constantin, et al.
(författare)
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Identification of cell surface determinants in Candida albicans reveals Tsa1p, a protein differentially localized in the cell
- 2003
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Ingår i: FEBS Letters. - : Elsevier. - 0014-5793 .- 1873-3468. ; 544:1-3, s. 228-235
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Tidskriftsartikel (refereegranskat)abstract
- To identify cell surface proteins of Candida albicans, the predominant fungal pathogen in humans, we have established an approach using a membrane impermeable biotin derivative in combination with affinity purification. We were able to identify 29 different proteins under two distinct conditions. Among mannoproteins, heat shock proteins and glycolytic enzymes we found thiol-specific antioxidant-like protein 1 (Tsa1p) to be differentially localized depending on the conditions applied. Only in hyphally grown cells Tsa1p was localized to the cell surface whereas in blastospores no surface but mainly nuclear localization was found. This indicates that cell surface expression of at least some proteins is mediated by differential translocation.
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31. |
- Wilczynska, Malgorzata, et al.
(författare)
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The spontaneous polymerization of plasminogen activator inhibitor type-2 and Z-antitrypsin are due to different molecular aberrations
- 2003
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 537:1-3, s. 11-16
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Tidskriftsartikel (refereegranskat)abstract
- The wild-type form of plasminogen activator inhibitor type-2 (PAI-2) and the pathogenic Z-mutant of alpha(1)-antitrypsin (alpha(1)AT) are serpins that spontaneously polymerize by the loop-sheet mechanism. Compared to the consensus serpin sequence, both PAI-2 and Z-alpha(1)AT have deviations in the so-called breach region located at the top of the A beta-sheet. In the case of Z-alpha(1)AT, conformational perturbations caused by a single amino acid substitution result in polymerization in vivo and predisposes to disease. To test whether the polymerization of PAI-2 is due to aberrations in the breach region, we constructed substitution mutants of PAI-2 with conserved residues in this region. Analysis of the mutants revealed that deviations in the breach region modulate but are not the major cause of PAI-2 polymerization. Rather, PAI-2 exists in a highly polymerogenic conformation and does not require conformational rearrangements before polymerization can take place.
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32. |
- Yang, Dan-Hui, et al.
(författare)
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The N-terminal domain of the light-harvesting chlorophyll a/b-binding protein complex (LHCII) is essential for its acclimative proteolysis
- 2000
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 466:2-3, s. 385-388
-
Tidskriftsartikel (refereegranskat)abstract
- Variations in the amount of the light-harvesting chlorophyll a/b-binding protein complex (LHCII) is essential for regulation of the uptake of light into photosystem II. An endogenous proteolytic system was found to be involved in the degradation of LHCII in response to elevated light intensities and the proteolysis was shown to be under tight regulation [Yang, D.-H. et al. (1998) Plant Physiol. 118, 827-834]. In this study, the substrate specificity and recognition site towards the protease were examined using reconstituted wild-type and mutant recombinant LHCII. The results show that the LHCII apoprotein and the monomeric form of the holoprotein are targeted for proteolysis while the trimeric form is not. The N-terminal domain of LHCII was found to be essential for recognition by the regulatory protease and the involvement of the N-end rule pathway is discussed. (C) 2000 Federation of European Biochemical Societies.
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33. |
- Zafra, Olga, et al.
(författare)
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A cytochrome c encoded by the nar operon is required for the synthesis of active respiratory nitrate reductase in Thermus thermophilus
- 2002
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 523:1-3, s. 99-102
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Tidskriftsartikel (refereegranskat)abstract
- A cytochrome c (NarC) is encoded as the first gene of the operon for nitrate respiration in Thermus thermophilus. NarC is required for anaerobic growth and for the synthesis of active nitrate reductase (NR). The alpha and delta subunits (NarG, NarJ) of the NR were constitutively expressed in narC::kat mutants, but NarG appeared in the soluble fraction instead of associated with the membranes. Our data demonstrate for NarC an essential role in the synthesis of active enzyme and for the attachment to the membrane of the respiratory NR from T. thermophilus.
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34. |
- Zhao, Ming, 1966-, et al.
(författare)
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Bcl-2 phosphorylation is required for inhibition of oxidative stress-induced lysosomal leak and ensuing apoptosis
- 2001
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 509:3, s. 405-412
-
Tidskriftsartikel (refereegranskat)abstract
- B-cell leukemia/lymphoma 2 (Bcl-2) blocks oxidant-induced apoptosis at least partly by stabilizing lysosomes. Here we report that phosphorylation of Bcl-2 may be required for these protective effects. J774 cells overexpressing wild-type Bcl-2 resist oxidant-induced lysosomal leak as well as apoptosis, and this protection is amplified by pretreatment with phorbol 12-myristate 13-acetate (which promotes protein kinase C (PKC)-dependent phosphorylation of Bcl-2). In contrast, cells overexpressing the Bcl-2 mutant S70A (which cannot be phosphorylated) are not protected in either circumstance. Transfection with Bcl-2(S70E), a constitutively active Bcl-2 mutant which does not require phosphorylation, is protective independent of PKC activation. In contrast, C2-ceramide, a putative protein phosphatase 2A activator, abolishes the protective effects of wild-type Bcl-2 overexpression but does not diminish protection afforded by Bcl-2(S70E). Additional results suggest that, perhaps as a consequence of lysosomal stabilization, Bcl-2 may prevent activation of phospholipase A2, an event potentially important in the ultimate initiation of apoptosis.
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35. |
- Zhao, Ming, 1966-, et al.
(författare)
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Delayed oxidant-induced cell death involves activation of phospholipase A2
- 2001
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 509:3, s. 399-404
-
Tidskriftsartikel (refereegranskat)abstract
- Short-term (1 h) exposure of cells to a low steady-state concentration of H2O2 causes no immediate cell death but apoptosis occurs several hours later. This delayed cell death may arise from activation of phospholipases, in particular phospholipase A2 (PLA2), which may destabilize lysosomal and mitochondrial membranes. Indeed, the secretory PLA2 (sPLA2) inhibitor 4-bromophenacyl bromide diminishes both delayed lysosomal rupture and apoptosis. Furthermore, sPLA2 activation by mellitin, or direct micro-injection of sPLA2, causes lysosomal rupture and apoptosis. Finally, B-cell leukemia/lymphoma 2 (Bcl-2) over-expression prevents oxidant-induced activation of PLA2, delayed lysosomal destabilization and apoptosis. This supports a causal association between PLA2 activation and delayed oxidant-induced cell death and suggests that Bcl-2 may suppress apoptosis by preventing PLA2 activation.
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36. |
- Zhao, Ming, 1966-, et al.
(författare)
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Protection against oxidant-mediated lysosomal rupture : a new anti-apoptotic activity of Bcl-2?
- 2000
-
Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 485:2-3, s. 104-108
-
Tidskriftsartikel (refereegranskat)abstract
- Bcl-2 antagonizes apoptosis through mechanisms which are not completely understood. We have proposed that apoptosis is initiated by minor lysosomal destabilization followed some time later by secondary massive lysosomal rupture. In J774 cells over-expressing Bcl-2, early oxidant-induced lysosomal destabilization is unaffected but secondary lysosomal rupture and apoptosis are suppressed, despite the fact that wild-type and Bcl-2 over-expressing cells degrade hydrogen peroxide at similar rates. It may be that Bcl-2 directly blocks the effects of released lysosomal enzymes and/or prevents downstream activation of unknown cytosolic pro-enzymes by released lysosomal hydrolases, suggesting a new and heretofore unknown activity of Bcl-2.
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37. |
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38. |
- Aspenström, Pontus
(författare)
-
The verprolin family of proteins : Regulators of cell morphogenesis and endocytosis
- 2005
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Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 579:24, s. 5253-5259
-
Forskningsöversikt (refereegranskat)abstract
- The verprolin family of proteins, WIP, CR16 and WIRE/WICH, has emerged as critical regulators of cytoskeletal organisation in vertebrate cells. The founding father of the family, verprolin, was originally identified in budding yeast and later shown to be needed for actin polymerisation during polarised growth and during endocytosis. The vertebrate verprolins regulate actin dynamics either by binding directly to actin, by binding the WASP family of proteins or by binding to other actin regulating proteins. Interestingly, also the vertebrate verprolins have been implicated in endocytosis, demonstrating that most of the functional modules in this fascinating group of proteins have been conserved from yeast to man.
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39. |
- Axler, Olof, et al.
(författare)
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Apolipoprotein M associates to lipoproteins through its retained signal peptide.
- 2008
-
Ingår i: FEBS Letters. - : Wiley. - 1873-3468 .- 0014-5793. ; 582:5, s. 826-828
-
Tidskriftsartikel (refereegranskat)abstract
- Apolipoprotein M (apoM) is predominantly associated with HDL. In this study, it was investigated whether apoM's uncleaved signal peptide is necessary for the protein's ability to associate with lipoproteins. ApoM with a cleavable signal peptide, Q22A, was expressed, together with wild-type apoM, in HEK293 cells. On size-exclusion chromatography, the elution profile of wild-type apoM was similar to that of human HDL-associated plasma apoM. In contrast, the size of the Q22A mutant corresponded to free, unassociated apoM. This strongly indicates that the signal peptide is indeed necessary for apoM's ability to associate with lipid.
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40. |
- Badhai, Jitendra, et al.
(författare)
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Posttranscriptional down-regulation of small ribosomal subunit proteinscorrelates with reduction of 18S rRNA in RPS19 deficiency
- 2009
-
Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 583:12, s. 2049-2053
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Tidskriftsartikel (refereegranskat)abstract
- Ribosomal protein S19 (RPS19) is mutated in patients with Diamond-Blackfan anemia (DBA). We hypothesized that decreased levels of RPS19 lead to a coordinated down-regulation of other ribosomal (r-)proteins at the subunit level. We show that small interfering RNA (siRNA) knock-down of RPS19 results in a relative decrease of small subunit (SSU) r-proteins (S20, S21 and S24) when compared to large subunit (LSU) r-proteins (L3, L9, L30 and L38). This correlates with a relative decrease in 18S rRNA with respect to 28S rRNA. The r-protein mRNA levels remain relatively unchanged indicating a post transcriptional regulation of r-proteins at the level of subunit formation.
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41. |
- Bailey, Leslie, et al.
(författare)
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Small molecule inhibitors of type III secretion in Yersinia block the Chlamydia pneumoniae infection cycle
- 2007
-
Ingår i: FEBS Letters. - : Elsevier. - 0014-5793 .- 1873-3468. ; 581:4, s. 587-595
-
Tidskriftsartikel (refereegranskat)abstract
- Intracellular parasitism by Chlamydiales is a complex process involving transmission of metabolically inactive particles that differentiate, replicate, and re-differentiate within the host cell. A type three secretion system (T3SS) has been implicated in this process. We have here identified small molecules of a chemical class of acylated hydrazones of salicylaldehydes that specifically blocks the T3SS of Chlamydia. These compounds also affect the developmental cycle showing that the T3SS has a pivotal role in the pathogenesis of Chlamydia. Our results suggest a previously unexplored avenue for development of novel anti-chlamydial drugs.
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42. |
- Bárány-Wallje, Elsa, et al.
(författare)
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Differential membrane perturbation caused by the cell penetrating peptide Tp10 depending on attached cargo
- 2007
-
Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 581:13, s. 2389-2393
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Tidskriftsartikel (refereegranskat)abstract
- The membrane leakage caused by the cell penetrating peptide Tp10, a variant of transportan, was studied in large unilamellar vesicles with the entrapped fluorophore calcein. The vesicles were composed of zwitterionic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine. A significant decrease in membrane leakage was found when the 55 kDa streptavidin protein was attached to Tp10. When a 5.4 kDa peptide nucleic acid molecule was attached, the membrane leakage was comparable to that caused by Tp10 alone. The results suggest that direct membrane effects may cause membrane translocation of Tp10 alone and of smaller complexes, whereas these effects do not contribute for larger cargoes.
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43. |
- Bhushan, Shashi, et al.
(författare)
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The role of the N-terminal domain of chloroplast targeting peptides in organellar protein import and miss-sorting
- 2006
-
Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 580:16, s. 3966-3972
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Tidskriftsartikel (refereegranskat)abstract
- We have analysed 385 mitochondrial and 567 chloroplastic signal sequences of proteins found in the organellar proteomes of Arabidopsis thaliana. Despite overall similarities, the first 16 residues of transit peptides differ remarkably. To test the hypothesis that the N-terminally truncated transit peptides would redirect chloroplastic precursor proteins to mitochondria, we studied import of the N-terminal deletion mutants of ELIP, PetC and Lhcb2.1. The results show that the deletion mutants were neither imported into chloroplasts nor miss-targeted to mitochondria in vitro and in vivo, showing that the entire transit peptide is necessary for correct targeting as well as miss-sorting.
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44. |
- Bugaeva, Elizaveta Y., et al.
(författare)
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One SmpB molecule accompanies tmRNA during its passage through the ribosomes
- 2008
-
Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 582:10, s. 1532-1536
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Tidskriftsartikel (refereegranskat)abstract
- tmRNA and SmpB are the main participants of trans-translation, a process which rescues the ribosome blocked during translation of non-stop mRNA. While a one-to-one stoichiometry of tmRNA to the ribosome is generally accepted, the number of SmpB molecules in the complex is still under question. We have isolated tmRNA-ribosome complexes blocked at different steps of the tmRNA path through the ribosome and analyzed the stoichiometry of the complexes. Ribosome, tmRNA and SmpB were found in equimolar amount in the tmRNA-ribosome complexes stopped at the position of the 2nd, 4th, 5th or the 11th codons of the coding part of the tmRNA.
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45. |
- Bäckman, Hans G, et al.
(författare)
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Binding of divalent cations is essential for the activity of the organellar peptidasome in Arabidopsis thaliana, AtPreP.
- 2009
-
Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 583:17, s. 2727-33
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Tidskriftsartikel (refereegranskat)abstract
- The dual-targeted mitochondrial and chloroplastic zinc metallooligopeptidase from Arabidopsis, AtPreP, functions as a peptidasome that degrades targeting peptides and other small unstructured peptides. In addition to Zn located in the catalytic site, AtPreP also contains two Mg-binding sites. We have investigated the role of Mg-binding using AtPreP variants, in which one or both sites were rendered unable to bind Mg(2+). Our results show that metal binding besides that of the active site is crucial for AtPreP proteolysis, particularly the inner site appears essential for normal proteolytic function. This is also supported by its evolutionary conservation among all plant species of PreP.
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46. |
- Chi, Celestine N., et al.
(författare)
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A conserved folding mechanism for PDZ domains
- 2007
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Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 581:6, s. 1109-1113
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Tidskriftsartikel (refereegranskat)abstract
- An important question in protein folding is whether the folding mechanism is sequence dependent and conserved for homologous proteins. In this work we compared the kinetic folding mechanism of five postsynaptic density protein-95, disc-large tumor suppressor protein, zonula occludens-1 (PDZ) domains, sharing similar topology but having different primary structures. Investigation of the different proteins under various experimental conditions revealed that the folding kinetics of each member of the PDZ family can be described by a model with two transition states separated by an intermediate. Moreover, the positions of the two transition states along the reaction coordinate (as given by their βT-values) are fairly constant for the five PDZ domains.
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47. |
- Dahlbäck, Björn, et al.
(författare)
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The anticoagulant protein C pathway.
- 2005
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Ingår i: FEBS Letters. - : Wiley. - 1873-3468 .- 0014-5793. ; 579:15, s. 3310-3316
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Forskningsöversikt (refereegranskat)
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48. |
- Dufe, Veronica T, et al.
(författare)
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Cloning, expression, characterisation and three-dimensional structure determination of Caenorhabditis elegans spermidine synthase
- 2005
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Ingår i: FEBS Letters. - : Wiley. - 1873-3468 .- 0014-5793. ; 579:27, s. 6037-6043
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Tidskriftsartikel (refereegranskat)abstract
- The polyamine synthesis enzyme spermidine synthase (SPDS) has been cloned from the model nematode Caenorhabditis elegans. Biochemical characterisation of the recombinantly expressed protein revealed a high degree of similarity to other eukaryotic SPDS with the exception of a low affinity towards the substrate decarboxylated S-adenosylmethionine (K-m = 110 mu M) and a less pronounced feedback inhibition by the second reaction product 5 '-methylthioadenosine (IC50 = 430 mu M). The C elegans protein that carries a nematode-specific insertion of 27 amino acids close to its N-terminus was crystallized, leading to the first X-ray structure of a dimeric eukaryotic SPDS. (c) 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
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49. |
- Ehrenberg, Måns, et al.
(författare)
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Systems Biology: Nobel Symposium 146.
- 2009
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Ingår i: FEBS letters. - : Wiley. - 1873-3468 .- 0014-5793. ; 583:24
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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50. |
- Eriksson, Charlotta, et al.
(författare)
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Dynamic properties of nuclear pore complex proteins in gp210 deficient cells
- 2004
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Ingår i: FEBS Letters. - : Wiley. - 0014-5793 .- 1873-3468. ; 572:1-3, s. 261-265
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Tidskriftsartikel (refereegranskat)abstract
- Gp210, an integral membrane protein of the nuclear pore complex (NPC), is believed to be involved in NPC biogenesis. To test this hypothesis, we have investigated dynamic properties of the NPC and distribution of NPC proteins in NIH/ 3T3 cells lacking gp210. POM121 (the other integral NPC protein) and NUP107 (of the NUP107/160 complex) were correctly distributed at the nuclear pores in the absence of gp210. Furthermore, fluorescence recovery after photobleaching experiments showed that POM121 and NUP107 remained stably associated at the NPCs. We conclude that gp210 cannot be required for incorporation of POM121 or NUP107 or be required for maintaining NPC stability.
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