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971.
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
972.
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
973.
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
974.
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975.
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
976.
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
977.
Altomare DA Menges CW Xu J Pei J Zhang L Tadevosyan A Neumann-Domer E Liu Z Carbone M Chudoba I Klein-Szanto AJ Testa JR 《PloS one》2011,6(4):e18828
The CDKN2A/ARF locus encompasses overlapping tumor suppressor genes p16(INK4A) and p14(ARF), which are frequently co-deleted in human malignant mesothelioma (MM). The importance of p16(INK4A) loss in human cancer is well established, but the relative significance of p14(ARF) loss has been debated. The tumor predisposition of mice singly deficient for either Ink4a or Arf, due to targeting of exons 1α or 1β, respectively, supports the idea that both play significant and nonredundant roles in suppressing spontaneous tumors. To further test this notion, we exposed Ink4a(+/-) and Arf(+/-) mice to asbestos, the major cause of MM. Asbestos-treated Ink4a(+/-) and Arf(+/-) mice showed increased incidence and shorter latency of MM relative to wild-type littermates. MMs from Ink4a(+/-) mice exhibited biallelic inactivation of Ink4a, loss of Arf or p53 expression and frequent loss of p15(Ink4b). In contrast, MMs from Arf(+/-) mice exhibited loss of Arf expression, but did not require loss of Ink4a or Ink4b. Mice doubly deficient for Ink4a and Arf, due to deletion of Cdkn2a/Arf exon 2, showed accelerated asbestos-induced MM formation relative to mice deficient for Ink4a or Arf alone, and MMs exhibited biallelic loss of both tumor suppressor genes. The tumor suppressor function of Arf in MM was p53-independent, since MMs with loss of Arf retained functional p53. Collectively, these in vivo data indicate that both CDKN2A/ARF gene products suppress asbestos carcinogenicity. Furthermore, while inactivation of Arf appears to be crucial for MM pathogenesis, the inactivation of both p16(Ink4a) and p19(Arf) cooperate to accelerate asbestos-induced tumorigenesis. 相似文献
978.
979.
Trophoblast stem (TS) cells are ideal models to investigate trophectoderm differentiation and placental development. Herein, we describe the derivation of rabbit trophoblast stem cells from embryonic stem (ES) cells. Rabbit ES cells generated in our laboratory were induced to differentiate in the presence of BMP4 and TS-like cell colonies were isolated and expanded. These cells expressed the molecular markers of mouse TS cells, were able to invade, give rise to derivatives of TS cells, and chimerize placental tissues when injected into blastocysts. The rabbit TS-like cells maintained self-renewal in culture medium with serum but without growth factors or feeder cells, whilst their proliferation and identity were compromised by inhibitors of FGFs and TGF-β receptors. Taken together, our study demonstrated the derivation of rabbit TS cells and suggested the essential roles of FGF and TGF-β signalings in maintenance of rabbit TS cell self-renewal. 相似文献
980.