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- Löhr, J, et al.
(författare)
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Quantification, immunoaffinity purification and sequence analysis of a pigment-dispersing hormone of the shore crab, Carcinus maenas (L.).
- 1993
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Ingår i: Comparative biochemistry and physiology. B, Comparative biochemistry. - 0305-0491. ; 104:4, s. 699-706
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Tidskriftsartikel (refereegranskat)abstract
- 1. A sensitive sandwich-ELISA for pigment-dispersing hormone (PDH) with a detection limit of approximately 5 fmol per well has been developed using primary IgG and secondary biotinylated IgG fractions from an antiserum against beta-PDH and streptavidin-peroxidase conjugate for detection. 2. ELISA determinations in different parts of the central nervous system of the shore crab Carcinus maenas revealed maximum levels of 15.1 pmol immunoreactive PDH in the two eyestalk ganglia of one crab, 3.6 pmol in the sinus glands, 2.8 pmol in the brain and 0.8 pmol in the thoracic ganglia. 3. Carcinus PDH was purified from whole eyestalk ganglia and sinus glands by use of a simple two-step purification procedure consisting of immunoaffinity-prepurification on an anti-PDH IgG-protein A-Sepharose column and HPLC. 4. Automated gas-phase sequencing of the purified peptide and FAB-mass spectroscopy unambiguously revealed the sequence of Carcinus PDH as NSELINSILGLPKVMNDAamide (M(r) 1927.2 Da), which is identical to the beta-PDH of other brachyuran crustaceans.
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| 2. |
- Axelson, H, et al.
(författare)
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A new variant 15; 16 translocation in mouse plasmacytoma leads to the juxtaposition of c-myc and immunoglobulin lambda
- 1991
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Ingår i: Oncogene. - 0950-9232. ; 6:12, s. 70-2263
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Tidskriftsartikel (refereegranskat)abstract
- Mouse plasmacytomas (MPCs) induced by pristane oil, or by a combination of pristane oil and Abelson virus, carry one of two chromosomal translocations. The typical 12; 15 translocation leads to the juxtaposition of c-myc and immunoglobulin heavy-chain sequences, whereas the 6; 15 translocation links the kappa light-chain locus with the pvt-1 (plasmacytoma variant translocation) locus, located at least 75kb 3' of c-myc [Cory, S., Graham, M., Webb, E., Corcoran, L. & Adams, J. (1985). EMBO J., 4, 675-681]. Unlike the human Burkitt's lymphoma-associated translocation, the lambda/myc juxtaposed variant translocation has not been found previously in MPCs. Using unconventional MPC induction systems in which the tumor precursor cell was induced to proliferate in a secondary host, we have recently identified a 15; 16 translocation in six of the derived MPCs [Wiener, F., Silva, S., Sugiyama, H., Babonits, M. & Klein, G. (1990). Genes Chromosomes Cancer, 2, 36-43]. Chromosome 16 harbors the lambda light-chain gene. To explore whether the 15; 16 translocation represents the lambda/myc juxtaposition, we have mapped the breakpoints on chromosomes 15 and 16 by pulsed-field gel electrophoresis (PFGE). The pvt-1 region was mapped to approximately 220 kb 3' of c-myc. The breakpoint on chromosome 15 in ABPC-Ch-163-10, one of the six 15; 16 translocation-carrying MPCs, was situated approximately 80 kb 3' of c-myc and 140 kb 5' of pvt-1b, the major breakpoint cluster region of the previously analysed 6; 15 variant MPCs. The breakpoint on chromosome 16 was found to cut between the V1 and C3 regions of the lambda locus. Co-migration experiments showed that the C3 and the myc gene were juxtaposed head to tail on the 15; 16 translocation chromosome. On the reciprocal product V1 was juxtaposed to pvt-1.
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| 3. |
- Henriksson, M, et al.
(författare)
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Nuclear colocalization of c-myc protein and hsp70 in cells transfected with human wild-type and mutant c-myc genes
- 1992
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Ingår i: Experimental Cell Research. - 0014-4827. ; 203:2, s. 94-383
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Tidskriftsartikel (refereegranskat)abstract
- Using immunofluorescence and electron microscopy we have studied the localization of wild-type and mutant c-myc proteins transiently expressed in CV-1 cells. In agreement with our previous observations, wild-type c-myc protein accumulated in large amorphous globules in the nucleus. All mutant proteins tested accumulated in the nucleus as well, but gave rise to morphologically different inclusion bodies. Many small globules appeared in cells transfected with D145-262 (deletion of amino acids 145-262), while cells transfected with D371-412 or D414-433 generated structures looking like a fine network or like beads on a string. In addition, a particulate cytoplasmic staining appeared in some cells transfected with the wild-type gene and in cells transfected with mutants D145-262 or D414-433. Since the c-myc protein has been reported to stimulate expression of exogenous hsp70 protein, we also examined the intracellular distribution of hsp70 in the transfected cells. Double immunofluorescence microscopy revealed that hsp70 codistributed with the c-myc protein in distinct globules in the nucleus of many but not all myc-positive cells. However, the levels of hsp70 transcripts were not significantly raised compared to nontransfected and vector-transfected cells. Likewise, the levels of hsp70 protein did not vary significantly. These findings indicate that overexpression of c-myc stimulates translocation of preexisting hsp70 from the cytoplasm into the nucleus, rather than influencing hsp70 expression. Conceivably, this may represent one of several mechanisms whereby the cell deals with excessive amounts of c-myc protein.
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| 4. |
- Wang, Y, et al.
(författare)
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Functional homology between N-myc and c-myc in murine plasmacytomagenesis : plasmacytoma development in N-myc transgenic mice
- 1992
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Ingår i: Oncogene. - 0950-9232. ; 7:6, s. 7-1241
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Tidskriftsartikel (refereegranskat)abstract
- Mouse plasmacytomas induced by pristane oil alone, or in combination with Abelson murine leukemia virus (A-MuLV), regularly carry one of three alternative chromosomal translocations that juxtapose c-myc to immunoglobulin heavy- or light-chain loci. E mu-c-myc transgenic mice develop translocation-free plasmacytomas after induction by pristane oil and/or A-MuLV [Sugiyama, H., Silva, S., Wang, Y., Weber, G., Babonits, M., Rosen, A., Wiener, F. & Klein, G. (1990). Int. J. Cancer, 46, 845-852]. In order to test whether another member of the myc family, N-myc, could play a similar role as c-myc, we treated E mu-N-myc transgenic mice with pristane and helper-free A-MuLV. Of 20 mice that received a single pristane injection followed by A-MuLV, 17 developed plasmacytomas with a mean latency period of 54 +/- 20 days. In a corresponding group that only received a single pristane injection, five out of six transgenic mice developed plasmacytomas with a mean latency period of 142 +/- 32 days. However, after three monthly injections of pristane, all 15 transgenic mice developed plasmacytomas with a mean latency period of 128 +/- 20 days. All plasmacytomas expressed the N-myc transgene, while none of them expressed either c-myc or endogenous N-myc. None of the tumors carried the usual plasmacytoma-associated translocations.
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