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991.
Shinkawa T Tan K Fujimoto M Hayashida N Yamamoto K Takaki E Takii R Prakasam R Inouye S Mezger V Nakai A 《Molecular biology of the cell》2011,22(19):3571-3583
Heat shock response is characterized by the induction of heat shock proteins (HSPs), which facilitate protein folding, and non-HSP proteins with diverse functions, including protein degradation, and is regulated by heat shock factors (HSFs). HSF1 is a master regulator of HSP expression during heat shock in mammals, as is HSF3 in avians. HSF2 plays roles in development of the brain and reproductive organs. However, the fundamental roles of HSF2 in vertebrate cells have not been identified. Here we find that vertebrate HSF2 is activated during heat shock in the physiological range. HSF2 deficiency reduces threshold for chicken HSF3 or mouse HSF1 activation, resulting in increased HSP expression during mild heat shock. HSF2-null cells are more sensitive to sustained mild heat shock than wild-type cells, associated with the accumulation of ubiquitylated misfolded proteins. Furthermore, loss of HSF2 function increases the accumulation of aggregated polyglutamine protein and shortens the lifespan of R6/2 Huntington's disease mice, partly through αB-crystallin expression. These results identify HSF2 as a major regulator of proteostasis capacity against febrile-range thermal stress and suggest that HSF2 could be a promising therapeutic target for protein-misfolding diseases. 相似文献
992.
Keng CT Akerström S Leung CS Poon LL Peiris JS Mirazimi A Tan YJ 《Microbes and infection / Institut Pasteur》2011,13(2):179-188
The severe acute respiratory syndrome coronavirus (SARS-CoV) 8b protein, which is not expressed by other known coronaviruses, can down-regulate the envelope (E) protein via a proteasome-dependent pathway. Here, we showed that the down-regulation of E is not dependent on the lysine residues on 8b and the reduction of polyubiquitination of E mutants is not correlated with their down-regulation by 8b, suggesting an ubiquitin-independent proteasome pathway is involved. A time-course study revealed that 8b was expressed at late-stages of SARS-CoV infection. By using Vero E6 cells stably expressing green fluorescence protein-tagged 8b, ectopic expression of 8b was shown to significantly reduce the production of progeny virus and down-regulate E expression. Taken together, these results suggest that 8b negatively modulates virus replication by down-regulating E via an ubiquitin-independent proteasome pathway. 相似文献
993.
Tang ZX Yang ZJ Fu SL Yang MY Li GR Zhang HQ Tan FQ Ren Z 《Journal of applied genetics》2011,52(1):31-33
A repetitive sequence of 491 bp, named pMD232-500, was isolated from S. cereale cv. Kustro using wheat SSR marker Xgwm232. GenBank BLAST search revealed that the sequence of pMD232-500 was highly similar to a part of retrotransposon Nusif-1.
Fluorescence in situ hybridization (FISH) analysis using pMD232-500 as probe indicated that only 14 Thinopyrum intermedium chromosomes and all the chromosomes of S. cereale cv. Kustro bear FISH signals, however, no FISH signals were observed on Dasypyrum villosum chromosomes. In addition, the FISH signals were distributed on whole arms except their terminal regions. Further genomic
in situ hybridization (GISH) analysis using genomic DNA from Pseudoroegneria spicata indicated that the 14 Th. intermedium chromosomes bearing FISH signals should belong to J genome. Thereafter, the repetitive elements pMD232-500 showed the unambiguous
features of genomic constitution of Th. intermedium. In addition, the results in the present study have indicated the similarity of genomes from Th. intermedium and S. cereale. 相似文献
994.
995.
Kwek Yan Chong Richard T. Corlett Darren C. J. Yeo Hugh T. W. Tan 《Biological invasions》2011,13(7):1571-1577
Worldwide spread and establishment of alien plant species continues to accelerate and damage ecological and agricultural systems.
Early warning and prevention of high-risk introductions is the most cost-effective approach to minimise losses while maximising
benefits, and the Australian Weed Risk Assessment (A-WRA) system has been the most well-developed and successful predictive
scheme. However, any system would be limited if the results or scores were confined to the locality of assessment. We compiled
A-WRA scores conducted in four tropical to sub-tropical regions and tested the accuracy of these scores for predicting naturalisations
for a separate well-documented, equatorial, exotic flora where weed risk assessments have never been conducted. Receiver Operating
Characteristic (ROC) curves reflect high accuracies of predictions, comparable to those in other studies. No significant differences
in accuracy were found between each regional subset and the compiled set of scores. Our results show that A-WRA scores assessed
at one locality can be used for others of similar climate, increasing the utility of every species’ assessment. A global database
of A-WRA scores would enable rapid local decision-making in border controls on imported plant species. A growing record of
species assessments would also facilitate monitoring evolutionary and ecological aspects of invasive species. 相似文献
996.
C. M. Wang L. C. Lo Z. Y. Zhu H. Y. Pang H. M. Liu J. Tan H. S. Lim R. Chou L. Orban G. H. Yue 《Marine biotechnology (New York, N.Y.)》2011,13(1):74-82
The caudal fin represents a fundamental design feature of fishes and plays an important role in locomotor dynamics in fishes.
The shape of caudal is an important parameter in traditional systematics. However, little is known about genes involved in
the development of different forms of caudal fins. This study was conducted to identify and map quantitative trait loci (QTL)
affecting the length of caudal fin and the ratio between tail length and standard body length in Asian seabass (Lates calcarifer). One F1 family containing 380 offspring was generated by crossing two unrelated individuals. One hundred and seventeen microsatellites
almost evenly distributed along the whole genome were genotyped. Length of caudal fin at 90 days post-hatch was measured.
QTL analysis detected six significant (genome-wide significant) and two suggestive (linkage-group-wide significant) QTL on
seven linkage groups. The six significant QTL explained 5.5–16.6% of the phenotypic variance, suggesting these traits were
controlled by multiple genes. Comparative genomics analysis identified several potential candidate genes for the length of
caudal fin. The QTL for the length of caudal fin detected for the first time in marine fish may provide a starting point for
the future identification of genes involved in the development of different forms of caudal fins in fishes. 相似文献
997.
Yu W Chan-On W Teo M Ong CK Cutcutache I Allen GE Wong B Myint SS Lim KH Voorhoeve PM Rozen S Soo KC Tan P Teh BT 《Genome biology》2011,12(9):R96-14
Background
Well differentiated papillary mesothelioma of the peritoneum (WDPMP) is a rare variant of epithelial mesothelioma of low malignancy potential, usually found in women with no history of asbestos exposure. In this study, we perform the first exome sequencing of WDPMP.Results
WDPMP exome sequencing reveals the first somatic mutation of E2F1, R166H, to be identified in human cancer. The location is in the evolutionarily conserved DNA binding domain and computationally predicted to be mutated in the critical contact point between E2F1 and its DNA target. We show that the R166H mutation abrogates E2F1's DNA binding ability and is associated with reduced activation of E2F1 downstream target genes. Mutant E2F1 proteins are also observed in higher quantities when compared with wild-type E2F1 protein levels and the mutant protein's resistance to degradation was found to be the cause of its accumulation within mutant over-expressing cells. Cells over-expressing wild-type E2F1 show decreased proliferation compared to mutant over-expressing cells, but cell proliferation rates of mutant over-expressing cells were comparable to cells over-expressing the empty vector.Conclusions
The R166H mutation in E2F1 is shown to have a deleterious effect on its DNA binding ability as well as increasing its stability and subsequent accumulation in R166H mutant cells. Based on the results, two compatible theories can be formed: R166H mutation appears to allow for protein over-expression while minimizing the apoptotic consequence and the R166H mutation may behave similarly to SV40 large T antigen, inhibiting tumor suppressive functions of retinoblastoma protein 1. 相似文献998.
The potential environmental suitability and economic viability of growing two biodiesel crops in marginal regions of Australia were explored. Firstly, we used spatial analysis techniques to identify marginal agricultural regions suitable for growing pongam (Pongamia pinnata) and Indian mustard (Brassica juncea), and determined the base socioeconomic viability of investments for the production of biodiesel in the identified areas. Secondly, we used climate change projections (target years 2020 to 2070) from the Commonwealth Scientific, Industrial and Research Organization Mk3.0 global circulation model generated for two emission scenarios (A1B and A1FI) to determine the shift in potential areas for these crops. Under the climate change scenarios tested, the total area suitable for growing pongam between 2040 and 2070 is substantially different from the suitable area under current climate, indicating that long-term investments in this perennial tree crop may not be viable in all regions, especially in southern Australia. There is a greater variation in suitability projections for Indian mustard, although there is more flexibility for cropping options given that it is an annual crop. However, future economic viability is likely to depend on the ability to receive renewable energy certificates for both crops and, in the case of pongam, the certified emission reductions. Opportunities exist for sustainable pongam agroforestry to supply biodiesel to regional towns, cattle stations and mines in northern Australia. 相似文献
999.
Survey of tyrosine kinase signaling reveals ROS kinase fusions in human cholangiocarcinoma 总被引:1,自引:0,他引:1
Gu TL Deng X Huang F Tucker M Crosby K Rimkunas V Wang Y Deng G Zhu L Tan Z Hu Y Wu C Nardone J MacNeill J Ren J Reeves C Innocenti G Norris B Yuan J Yu J Haack H Shen B Peng C Li H Zhou X Liu X Rush J Comb MJ 《PloS one》2011,6(1):e15640
Cholangiocarcinoma, also known as bile duct cancer, is the second most common primary hepatic carcinoma with a median survival of less than 2 years. The molecular mechanisms underlying the development of this disease are not clear. To survey activated tyrosine kinases signaling in cholangiocarcinoma, we employed immunoaffinity profiling coupled to mass spectrometry and identified DDR1, EPHA2, EGFR, and ROS tyrosine kinases, along with over 1,000 tyrosine phosphorylation sites from about 750 different proteins in primary cholangiocarcinoma patients. Furthermore, we confirmed the presence of ROS kinase fusions in 8.7% (2 out of 23) of cholangiocarcinoma patients. Expression of the ROS fusions in 3T3 cells confers transforming ability both in vitro and in vivo, and is responsive to its kinase inhibitor. Our data demonstrate that ROS kinase is a promising candidate for a therapeutic target and for a diagnostic molecular marker in cholangiocarcinoma. The identification of ROS tyrosine kinase fusions in cholangiocarcinoma, along with the presence of other ROS kinase fusions in lung cancer and glioblastoma, suggests that a more broadly based screen for activated ROS kinase in cancer is warranted. 相似文献
1000.