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961.
962.
Aimin Wang Yan Wang Zhifeng Gu Sifa Li Yaohua Shi Ximing Guo 《Marine biotechnology (New York, N.Y.)》2011,13(2):275-283
The pearl oyster, Pinctada martensii, is the primary species used for the aquaculture production of marine pearls in China and Japan. Genetic tools and resources
are needed to study the genome of this species and to understand the molecular basis of development, growth, host defense,
pearl formation, and other important traits. In this study, we developed a set of expressed sequence tags (ESTs) for P. martensii. We constructed cDNA libraries from adult tissues and sequenced 7,128 ESTs. Clustering analysis identified 788 contigs (covering
5,769 ESTs) and 1,351 singletons, yielding a total of 2,139 unique genes. Of these unique genes, only 935 had significant
(E-value ≤ 0.005) hits in GenBank, and the remaining 1,204 (56.3%) were novel. Most of the known genes are related to cellular
structure, protein binding, and metabolic processes. Putative host-defense genes (86) were identified including C-type lectin,
ferritin, polyubiquitin, proteases, protease inhibitors, scavenger receptors, heat shock proteins, and RAS oncogenes. The
EST sequences developed in this study provide a valuable resource for future efforts on gene identification, marker development,
and studies on molecular mechanism of host defense in pearl oysters. 相似文献
963.
The purpose of this study was to assess if there was trophic niche overlap of silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis) in four large freshwater ecosystems from southern China using stable carbon and nitrogen isotopes (δ13C and δ15N). Multivariate analysis of variance (MANOVA) on the δ13C and δ15N values measured from muscle tissue indicates trophic niche overlap in one unproductive and one highly productive large system
and trophic niche segregation in two systems with moderate watershed size and productivity. For these two coexisting planktivorous
fish, which were hitherto believed to occupy different trophic niches, this study demonstrated that the degree of their trophic
niche overlap varied according to ecosystem properties. 相似文献
964.
965.
966.
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
967.
Activating mutations in the Kras gene are commonly found in some but not all epithelial cancers. In order to understand the susceptibility of different epithelial tissues to Kras-induced tumorigenesis, we introduced one of the most common Kras mutations, Kras(G12D), broadly in epithelial tissues. We used a mouse model in which the G12D mutation is placed in the endogenous Kras locus controlled by inducible, Cre-mediated recombination in tissues expressing cytokeratin 19 including the oral cavity, GI tract, lungs, and ducts of the liver, kidney, and the pancreas. Introduction of the Kras(G12D) mutation in adult mouse tissues led to neoplastic changes in some but not all of these tissues. Notably, many hyperplasias, metaplasias and adenomas were observed in the oral cavity, stomach, colon and lungs, suggesting that exposure to products of the outside environment promotes Kras(G12D)-initiated tumorigenesis. However, environmental exposure did not consistently correlate with tumor formation, such as in the small intestine, suggesting that there are also intrinsic differences in susceptibility to Kras activation. The pancreas developed small numbers of mucinous metaplasias with characteristics of early stage pancreatic intraepithelial neoplasms (PanINs), supporting the hypothesis that pancreatic ducts have the potential to give rise pancreatic cancer. 相似文献
968.
969.
Diribarne M Mata X Chantry-Darmon C Vaiman A Auvinet G Bouet S Deretz S Cribiu EP de Rochambeau H Allain D Guérin G 《PloS one》2011,6(4):e19281
The fur of common rabbits is constituted of 3 types of hair differing in length and diameter while that of rex animals is essentially made up of amazingly soft down-hair. Rex short hair coat phenotypes in rabbits were shown to be controlled by three distinct loci. We focused on the "r1" mutation which segregates at a simple autosomal-recessive locus in our rabbit strains. A positional candidate gene approach was used to identify the rex gene and the corresponding mutation. The gene was primo-localized within a 40 cM region on rabbit chromosome 14 by genome scanning families of 187 rabbits in an experimental mating scheme. Then, fine mapping refined the region to 0.5 cM (Z = 78) by genotyping an additional 359 offspring for 94 microsatellites present or newly generated within the first defined interval. Comparative mapping pointed out a candidate gene in this 700 kb region, namely LIPH (Lipase Member H). In humans, several mutations in this major gene cause alopecia, hair loss phenotypes. The rabbit gene structure was established and a deletion of a single nucleotide was found in LIPH exon 9 of rex rabbits (1362delA). This mutation results in a frameshift and introduces a premature stop codon potentially shortening the protein by 19 amino acids. The association between this deletion and the rex phenotype was complete, as determined by its presence in our rabbit families and among a panel of 60 rex and its absence in all 60 non-rex rabbits. This strongly suggests that this deletion, in a homozygous state, is responsible for the rex phenotype in rabbits. 相似文献
970.
Keratoconus, historically viewed as a non-inflammatory disease, is an ectatic corneal disorder associated with progressive thinning of the corneal stroma. Recently, a few inflammatory mediators have been reported to be elevated in the tear fluid of keratoconus patients. Consequently, we investigated a wide range of inflammation regulating cytokines in the tears and sera of keratoconus and control subjects. Interleukin (IL)-1β, IL-4, IL-6, IL-10, IL-12, IL-13, IL-17, interferon (IFN)-γ, chemokine C-C motif ligand 5 (CCL5) and tumor necrosis factor (TNF)-α were tested in tear samples and sera of keratoconus and control individuals by multiplex immuno-bead assays. Selected cytokines were further tested by standard ELISA on pooled tear samples. All cytokines in the sera were generally low, with no significant changes between keratoconus and control subjects. However, in tear fluids, clear differences were detected between the two groups. These differences include increased IL-6, and decreased IL-12, TNF-α, IFN-γ, IL-4, IL-13 and CCL5 in keratoconus compared to control tear fluids. The decreases in IL-12, TNF-α and CCL5 were statistically significant, while the IL-13 decrease was statistically significant in the severe keratoconus group only. IL-17 could not be detected by multiplex immuno-bead assay, but showed an increase in keratoconus by conventional ELISA on a limited number of pooled tear samples. Our findings confirm increased IL-6, but dispute earlier reports of increased TNF-α, and suggest a cytokine imbalance in keratoconus disrupting corneal homeostasis. Moreover, an increase in IL-17 suggests tissue degenerative processes at work, contributing to the thinning and weakening of the corneal connective tissue in keratoconus. 相似文献