| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
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| 3. |
- Abdallah, J, et al.
(författare)
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Charged particle multiplicity in three-jet events and two-gluon systems
- 2005
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; C:44, s. 311-331
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Tidskriftsartikel (refereegranskat)abstract
- The charged particle multiplicity in hadronic three-jet events from Z decays is investigated. The topology dependence of the event multiplicity is found to be well described by a modified leading logarithmic prediction. A parameter fit of the prediction to the data yields a measurement of the colour factor ratio C-A/C-F with the result C-A/C-F = 2.261 +/- 0.014(stat). +/- 0.036(exp). +/- 0-066(theo). in agreement with the SU(3) expectation of QCD. The quark-related contribution to the event multiplicity is subtracted from the three-jet event multiplicity resulting in a measurement of the multiplicity of two-gluon colour-singlet states over a wide energy range. The ratios r = N-gg(s)/Ng (g) over bar (s) of the gluon and quark multiplicities and r((1)) = N'(gg)(s)/N'g (g) over bar (s) of their derivatives are compared with perturbative calculations. While a good agreement between calculations and data is observed for r((1)), larger deviations are found for r indicating that non-perturbative effects are more important for r than for r((1)).
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| 4. |
- Abdallah, J, et al.
(författare)
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Production of Xi(0)(c) and Xi(b) in Z decays and lifetime measurement of Xi(b)
- 2005
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; C:44, s. 299-309
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Tidskriftsartikel (refereegranskat)abstract
- The charmed strange baryon Xi(c)(0) was searched for in the decay channel Xi(c)(0) -> Xi(-)pi(+), and the beauty strange baryon Xi(b) in the inclusive channel Xi(b) -> Xi(-)l(-)(nu) over barX, using the 3.5 million hadronic Z events collected by the DELPHI experiment in the years 1992-1995. The Xi(-) was reconstructed through the decay AT, using a constrained fit method for cascade decays. An iterative discriminant analysis was used for the Xi(c)(0) and Xi(b) selection. The production rates were measured to be f(Xi c)(0) x BR(Xi(c)(0) -> Xi(-)pi(+) = (4.7 +/- 1.4(stat.) +/- 1.1(syst.)) x 10(-4) per hadronic Z decay, and BR(b -> Xi(b))xBR(Xi(b) -> Xi(-)l(-)X) = (3.0 +/- 1.0(stat.) +/- 0.3(syst.)) x 10(-4) for each lepton species (electron or muon). The lifetime of the Xi(b) baryon was measured to be tau(Xi b) = 1.45(-0.43)(+0.55)(stat.)+/- 0.13(syst.) ps. A combination with the previous DELPHI lifetime measurement gives tau(Xi b) = 1.48(-0.31)(+0.40)(stat.)+/- 0.12(syst.) ps.
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| 5. |
- Abdallah, J, et al.
(författare)
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Coherent soft particle production in Z decays into three jets
- 2005
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Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 605:1-2, s. 37-48
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Tidskriftsartikel (refereegranskat)abstract
- Low-energy particle production perpendicular to the event plane in three-jet events produced in Z decays in e(+)e(-) annihilation is measured and compared to that perpendicular to the event axis in two-jet events. The topology dependence of the hadron production ratio is found to agree with a leading-order QCD prediction. This agreement and especially the need for the presence of a destructive interference term gives evidence for the coherent nature of gluon radiation. Hadron production in three-jet events is found to be directly proportional to a single topological scale function of the inter-jet angles. The slope of the dependence of the multiplicity with respect to the topological scale was measured to be 2.211 +/- 0.014(stat.) +/- 0.053(syst.) in good agreement with the expectation given by the colour-factor ratio C-A/C-F = 9/4. This result strongly supports the assumption of local parton-hadron duality, LPHD, at low hadron momentum.
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| 6. |
- Abdallah, J, et al.
(författare)
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Determination of A(FB)(b) at the Z pole using inclusive charge reconstruction and lifetime tagging
- 2005
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 40:1, s. 1-25
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Tidskriftsartikel (refereegranskat)abstract
- A novel high precision method measures the b-quark forward-backward asymmetry at the Z pole on a sample of 3,560,890 hadronic events collected with the DELPHI detector in 1992 to 2000. An enhanced impact parameter tag provides a high purity b sample. For event hemispheres with a reconstructed secondary vertex the charge of the corresponding quark or anti-quark is determined using a neural network which combines in an optimal way the full available charge information from the vertex charge, the jet charge and from identified leptons and hadrons. The probability of correctly identifying b-quarks and anti-quarks is measured on the data themselves comparing the rates of double hemisphere tagged like-sign and unlike-sign events. The b-quark forward-backward asymmetry is determined from the differential asymmetry, taking small corrections due to hemisphere correlations and background contributions into account. The results for different centre-of-mass energies are: A(FB)(b) ( 89.449 GeV) = 0.0637 +/- 0.0143( stat.) +/- 0.0017( syst.), A(FB)(b) ( 91.231 GeV) = 0.0958 +/- 0.0032( stat.) +/- 0.0014( syst.), A(FB)(b) ( 92.990 GeV) = 0.1041 +/- 0.0115( stat.) +/- 0.0024( syst.). Combining these results yields the b-quark pole asymmetry A(FB)(b0) = 0.0972 +/- 0.0030( stat.) +/- 0.0014( syst.).
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| 7. |
- Abdallah, J, et al.
(författare)
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Search for eta(b) in two-photon collisions at LEP II with the DELPHI detector
- 2006
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Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 634:4, s. 340-346
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Tidskriftsartikel (refereegranskat)abstract
- The pseudoscalar meson eta(b) has been searched for in two-photon interactions at LEP II. The data sample corresponds to a total integrated luminosity of 617 pb(-1) at centre-of-mass energies ranging from 161 to 209 GeV. Upper limits at a confidence level of 95% on the product Gamma(gamma gamma) (eta(b)) x BR(eta(b)) are 190, 470 and 660 eV/c(2) for the eta(b) decaying into 4, 6 and 8 charged particles, respectively.
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| 8. |
- Berg, S., et al.
(författare)
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Serotypes of Streptococcus pneumoniae isolated from blood and cerebrospinal fluid related to vaccine serotypes and to clinical characteristics
- 2006
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Ingår i: Scand J Infect Dis. - : Informa UK Limited. - 0036-5548. ; 38:6-7, s. 427-32
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Tidskriftsartikel (refereegranskat)abstract
- Pneumococci isolated from blood and cerebrospinal fluid from 1998 to 2001 in 2 counties in south-west Sweden were serotyped with the capsular reaction test. Of the 836 strains, 353 (42%), 598 (72%) and 789 (94%) belonged to serotypes included in the 7- and 11-valent pneumococcal conjugate vaccines and in the 23-valent polysaccharide vaccine, respectively. The most common serotype was type 1 (119 isolates) followed in descending frequency by serotypes 7F, 9V, 14, 4 and 12F (90-49 isolates per serotype). The coverage rates of the 7- and 11-valent conjugate vaccines among 58 strains isolated from children and adolescents 0-19 y of age were 46% and 93%, respectively. A comparison of clinical characteristics of infections caused by different serotypes showed that types 1 and 7F were less commonly associated with severe underlying diseases, that patients infected with these serotypes were younger than the average and, thus, had a lower case-fatality rate.
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| 9. |
- Bjornvold, M., et al.
(författare)
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FOXP3 polymorphisms in type 1 diabetes and coeliac disease
- 2006
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Ingår i: J Autoimmun. - : Elsevier BV. - 0896-8411. ; 27:2, s. 140-4
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Tidskriftsartikel (refereegranskat)abstract
- The FOXP3 gene encodes a transcription factor thought to be essential for the development and function of T regulatory cells. Two previous studies have tested common polymorphisms in FOXP3 for association with type 1 diabetes (T1D) with conflicting results. The aim of our study was to see whether there is any evidence of association between the FOXP3 polymorphisms previously reported to be associated with T1D, in a Caucasian population regarding T1D and coeliac disease (CD). We further looked for evidence of interaction between FOXP3 polymorphisms and HLA-DR3 in conferring susceptibility to T1D. Initially, we analysed two microsatellites in the FOXP3 gene in 363 T1D nuclear families. Our results indicated an association between FOXP3 and T1D (global p=0.004) and a possible interaction between FOXP3 and the HLA-DR3-DQ2 susceptibility haplotype. We then genotyped an additional independent set of 826 T1D patients and 1459 controls as well as one CD dataset consisting of 325 families. A similar tendency was revealed in the CD family material (pnc=0.055 for the associated allele). On the other hand, we were unable to reproduce our initial findings in the T1D case-control dataset (global p=0.6). Our results suggest that the tested FOXP3 markers do not have any major impact on susceptibility for these diseases.
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| 10. |
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| 11. |
- Adamovic, Svetlana, 1965, et al.
(författare)
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Fine mapping study in Scandinavian families suggests association between coeliac disease and haplotypes in chromosome region 5q32.
- 2008
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Ingår i: Tissue Antigens. - : Wiley. - 1399-0039 .- 0001-2815. ; 71:1, s. 27-34
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Tidskriftsartikel (refereegranskat)abstract
- The previous genome-wide scan in Scandinavian families supported earlier evidence for linkage of a region on chromosome 5 (5q31–33) to coeliac disease. This study deals with further genetic mapping of an 18 cM region, spanning from marker GAh18A (131.87 Mb) to D5S640 (149.96 Mb). Linkage and association analyses were performed in a two-step approach. First, seven microsatellites were added. Strong evidence for linkage was obtained with a Zlr score of 3.96, Pnc = 4 × 10−5 at marker D5S436. The strongest association was with a haplotype consisting of the markers D5S2033 and D5S2490 (Pnc < 0.001). In the second step, we added 17 microsatellites and 69 single nucleotide polymorphisms (SNPs) to the analysis. These markers were located close to or within candidate genes across the region of approximately 7 Mb beneath the linkage peak marked by D5S2017 and D5S812. A substantial increase of the linkage signal with a maximum Zlr score of 4.6 at marker rs1972644 (Pnc = 2 × 10−6) was obtained and several SNPs showed association. Seven SNPs that individually showed the strongest association were genotyped in a second independent family sample set (225 trios). In the trio family sample as well as in the multiplex family sample, the strongest association was found with SNPs within the region flanked by the associated microsatellites D5S2033 and D5S2490 at 5q32.
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| 12. |
- Amundsen, S. S., et al.
(författare)
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Association analysis of MYO9B gene polymorphisms with celiac disease in a Swedish/Norwegian cohort
- 2006
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Ingår i: Hum Immunol. - : Elsevier BV. - 0198-8859. ; 67:4-5, s. 341-5
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Tidskriftsartikel (refereegranskat)abstract
- Association between myosin IXB (MYO9B) gene variants and celiac disease (CD) has been reported in a study of a Dutch cohort. Six single nucleotide polymorphisms (SNPs) within the 3' part of the MYO9B gene showed significant genetic association and formed an associated haplotype. The current study aimed to replicate these findings in a Swedish/Norwegian cohort. Genotyping of the three SNPs which tagged the associated haplotype was performed in a CD family dataset (n = 326) and in an additional set of healthy controls (n = 562). Although our material provided reasonable power to detect the previously observed association, we were unable to replicate association with these SNPs. Lack of reproducibility could be explained by no or negligible contribution of MYO9B to the genetic predisposition to CD in the Swedish/Norwegian population. Alternatively, it might be due to variable linkage disequilibria in distinct populations in the tested SNPs and a causative mutation yet to be identified or to false positive findings (type I error) in the Dutch study.
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| 13. |
- McKeith, IG, et al.
(författare)
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Diagnosis and management of dementia with Lewy bodies - Third report of the DLB consortium
- 2005
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Ingår i: Neurology. - : Ovid Technologies (Wolters Kluwer Health). - 1526-632X .- 0028-3878. ; 65:12, s. 1863-1872
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Forskningsöversikt (refereegranskat)abstract
- The dementia with Lewy bodies (DLB) Consortium has revised criteria for the clinical and pathologic diagnosis of DLB incorporating new information about the core clinical features and suggesting improved methods to assess them. REM sleep behavior disorder, severe neuroleptic sensitivity, and reduced striatal dopamine transporter activity on functional neuroimaging are given greater diagnostic weighting as features suggestive of a DLB diagnosis. The 1-year rule distinguishing between DLB and Parkinson disease with dementia may be difficult to apply in clinical settings and in such cases the term most appropriate to each individual patient should be used. Generic terms such as Lewy body (LB) disease are often helpful. The authors propose a new scheme for the pathologic assessment of LBs and Lewy neurites (LN) using alpha-synuclein immunohistochemistry and semiquantitative grading of lesion density, with the pattern of regional involvement being more important than total LB count. The new criteria take into account both Lewy-related and Alzheimer disease (AD)-type pathology to allocate a probability that these are associated with the clinical DLB syndrome. Finally, the authors suggest patient management guidelines including the need for accurate diagnosis, a target symptom approach, and use of appropriate outcome measures. There is limited evidence about specific interventions but available data suggest only a partial response of motor symptoms to levodopa: severe sensitivity to typical and atypical antipsychotics in similar to 50%, and improvements in attention, visual hallucinations, and sleep disorders with cholinesterase inhibitors.
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| 14. |
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| 15. |
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| 16. |
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| 17. |
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Ek, K, et al.
(författare)
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Distribution of palladium, platinum and rhodium in birds of prey
- 2005
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Ingår i: Palladium Emissions in the Environment: Analytic, Environmental Assessment and Health Effects.. - : Springer-Verlag Berlin Heidelberg New York. - 3540292195 ; , s. 537-547
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 22. |
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| 23. |
- Ek, M., et al.
(författare)
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Microsatellite markers for powdery mildew resistance in pea (Pisum sativum L.)
- 2005
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Ingår i: Hereditas. - : Springer Science and Business Media LLC. - 1601-5223 .- 0018-0661. ; 142, s. 86-91
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Tidskriftsartikel (refereegranskat)abstract
- Powdery mildew is a common disease of field pea, Pisum sativum L., and is caused by the ascomycete fungus Erysiphe pisi. It can cause severe damage in areas where pea is cultivated. Today breeders want to develop new pea lines that are resistant to the disease. To make the breeding process more efficient, it is desirable to find genetic markers for use in a marker-assisted selection (MAS) strategy. In this study, microsatellites (SSR) were used to find markers linked to powdery mildew resistance. The resistant pea cultivar '955180' and the susceptible pea cultivar 'Majoret' were crossed and F-2 plants were screened with SSR markers, using bulked segregant analysis. A total of 315 SSR markers were screened out of which five showed linkage to the powdery mildew resistance gene. No single marker was considered optimal for inclusion in a MAS program. Instead, two of the markers can be used in combination, which would result in only 1.6% incorrectly identified plants. Thus SSR markers can be successfully used in marker-assisted selection for powdery mildew resistance breeding in pea.
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| 24. |
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| 25. |
- Ek, S, et al.
(författare)
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Oligohydramnios in uncomplicated pregnancies beyond 40 completed weeks. A prospective, randomised, pilot study on maternal and neonatal outcomes
- 2005
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Ingår i: Fetal diagnosis and therapy. - : S. Karger AG. - 1015-3837 .- 1421-9964. ; 20:3, s. 182-185
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Tidskriftsartikel (refereegranskat)abstract
- <i>Objectives:</i> In low-risk pregnancies, the management of oligohydramnios is not clear. The aim of this study was to compare maternal and neonatal outcomes in cases of isolated oligohydramnios randomised to either induction of labour or expectant management. <i>Methods:</i> 87 women pregnant beyond 40 completed weeks were asked to participate in the study. Fifty-four accepted and were randomised at 288 days of pregnancy. Twenty-six were randomised to expectant management and 28 to induction of labour. The primary maternal outcome was the mode of delivery and the primary neonatal outcomes were cord blood pH and Apgar score at delivery. <i>Results:</i> No significant differences were found for any important maternal or neonatal outcome. <i>Conclusion:</i> Based on these results, the decisions about management could be individualised. Even though the number of patients included was small, these results are well in concordance with others.
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| 26. |
- Ek, Ulla, et al.
(författare)
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Etik och juridik
- 2009. - 1
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Ingår i: Psykolog i skolan. - Lund : Studentlitteratur. - 9789144054452 ; , s. 35-82
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Kapitlet handlar om etiska och juridiska aspekter avseende skolpsykologer.
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| 27. |
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| 28. |
- Johansson, S, et al.
(författare)
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Intracellular targeting of CEA results in Th1-type antibody responses following intradermal genetic vaccination by a needle-free jet injection device
- 2007
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Ingår i: TheScientificWorldJournal. - : Hindawi Limited. - 1537-744X. ; 7, s. 987-999
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Tidskriftsartikel (refereegranskat)abstract
- The route and method of immunization, as well as the cellular localization of the antigen, can influence the generation of an immune response. In general, intramuscular immunization results in Th1 responses, whereas intradermal delivery of DNA by gene gun immunization often results in more Th2 responses. Here we investigate how altering the cellular localization of the tumor antigen CEA (carcinoembryonic antigen) affects the quality and amplitude of DNA vaccine-induced antibody responses in mice following intradermal delivery of DNA by a needle-free jet injection device (Biojector). CEA was expressed either in a membrane-bound form (wild-type CEA) or in two truncated forms (CEA6 and CEA66) with cytoplasmic localization, where CEA66 was fused to a promiscuous T-helper epitope from tetanus toxin. Repeated intradermal immunization of BALB/c mice with DNA encoding wild-type CEA produced high antibody titers of a mixed IgG1/IgG2a ratio. In contrast, utilizing the DNA construct that resulted in intracellular targeting of CEA led to a reduced capacity to induce CEA-specific antibodies, but instead induced a Th1-biased immune response.
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| 29. |
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| 30. |
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| 31. |
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| 32. |
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| 33. |
- Mathey, EK, et al.
(författare)
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Neurofascin as a novel target for autoantibody-mediated axonal injury
- 2007
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 0022-1007 .- 1540-9538. ; 204:10, s. 2363-2372
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Tidskriftsartikel (refereegranskat)abstract
- Axonal injury is considered the major cause of disability in patients with multiple sclerosis (MS), but the underlying effector mechanisms are poorly understood. Starting with a proteomics-based approach, we identified neurofascin-specific autoantibodies in patients with MS. These autoantibodies recognize the native form of the extracellular domains of both neurofascin 186 (NF186), a neuronal protein concentrated in myelinated fibers at nodes of Ranvier, and NF155, the oligodendrocyte-specific isoform of neurofascin. Our in vitro studies with hippocampal slice cultures indicate that neurofascin antibodies inhibit axonal conduction in a complement-dependent manner. To evaluate whether circulating antineurofascin antibodies mediate a pathogenic effect in vivo, we cotransferred these antibodies with myelin oligodendrocyte glycoprotein–specific encephalitogenic T cells to mimic the inflammatory pathology of MS and breach the blood–brain barrier. In this animal model, antibodies to neurofascin selectively targeted nodes of Ranvier, resulting in deposition of complement, axonal injury, and disease exacerbation. Collectively, these results identify a novel mechanism of immune-mediated axonal injury that can contribute to axonal pathology in MS.
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| 34. |
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| 35. |
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| 36. |
- Popovic, K, et al.
(författare)
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Fine specificity of the Ro/SSA autoantibody response in relation to serological and clinical findings in 96 patients with self-reported cutaneous symptoms induced by the sun
- 2007
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Ingår i: Lupus. - : SAGE Publications. - 0961-2033 .- 1477-0962. ; 16:1, s. 10-17
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Tidskriftsartikel (refereegranskat)abstract
- Anti-Ro/SSA assays assist the clinician in distinguishing autoimmune diseases such as Sjögrenś syndrome (SS), systemic lupus erythematosus (SLE) and subacute cutaneous lupus erythematosus (SCLE). The objective of the study was to investigate the fine specificity of the autoantibodies in relation to clinical presentation as well as environmental and endogenous factors such as photosensitivity, smoking and immunoglobulin (Ig) levels in patients with Ro/SSA autoantibodies. Serum samples from 96 anti-Ro/SSA positive photosensitive patients were tested for autoantibody levels by enzyme-linked immunosorbent assay (ELISA) using purified recombinant Ro52 kd, Ro60 kd and La proteins as antigens. The highest levels of anti-Ro52 and anti-La were observed in patients with primary SS, and the lowest levels of anti-Ro52 in chronic cutaneous lupus erythematosus (CCLE). SCLE patients with systemic disease (SLE and/or SS) showed higher levels of anti-Ro52 than SCLE limited to the skin. A correlation between high serum levels of IgG and anti-Ro52 ( P < 0.01) and between IgA and anti-Ro52 ( P < 0.05) and anti-Ro60 ( P < 0.05) was found. Polymorphic light eruption (PLE) was common in all diagnostic groups but did not correlate with autoantibody levels. Smoking was more common in lupus patients than in SS patients. Our findings thus propose different mechanisms for different clinical presentations of Ro/SSA positive patients. The testing of anti-Ro52 antibodies might serve as a prognostic tool in photosensitive cutaneous diseases.
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| 37. |
- Rainey-Barger, EK, et al.
(författare)
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Dimerization of ERp29, a PDI-like protein, is essential for its diverse functions
- 2007
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Ingår i: Molecular biology of the cell. - : American Society for Cell Biology (ASCB). - 1059-1524 .- 1939-4586. ; 18:4, s. 1253-1260
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Tidskriftsartikel (refereegranskat)abstract
- Protein disulfide isomerase (PDI)-like proteins act as oxido-reductases and chaperones in the endoplasmic reticulum (ER). How oligomerization of the PDI-like proteins control these activities is unknown. Here we show that dimerization of ERp29, a PDI-like protein, regulates its protein unfolding and escort activities. We have demonstrated previously that ERp29 induces the local unfolding of polyomavirus in the ER, a step required for viral infection. We now find that, in contrast to wild-type ERp29, a mutant ERp29 (D42A) that dimerizes inefficiently is unable to unfold polyomavirus or stimulate infection. A compensatory mutation that partially restores dimerization to the mutant ERp29 (G37D/D42A) rescues ERp29 activity. These results indicate that dimerization of ERp29 is crucial for its protein unfolding function. ERp29 was also suggested to act as an escort factor by binding to the secretory protein thyroglobulin (Tg) in the ER, thereby facilitating its secretion. We show that this escort function likewise depends on ERp29 dimerization. Thus our data demonstrate that dimerization of a PDI-like protein acts to regulate its diverse ER activities.
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| 38. |
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