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991.
992.
993.
Fu-Zheng Wei Ziyang Cao Xi Wang Hui Wang Mu-Yan Cai Tingting Li Naoko Hattori Donglai Wang Yipeng Du Boyan Song Lin-Lin Cao Changchun Shen Lina Wang Haiying Wang Yang Yang Dan Xie Fan Wang Toshikazu Ushijima Ying Zhao Wei-Guo Zhu 《Autophagy》2015,11(12):2309-2322
Macroautophagy is an evolutionarily conserved cellular process involved in the clearance of proteins and organelles. Although the autophagy regulation machinery has been widely studied, the key epigenetic control of autophagy process still remains unknown. Here we report that the methyltransferase EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit) epigenetically represses several negative regulators of the MTOR (mechanistic target of rapamycin [serine/threonine kinase]) pathway, such as TSC2, RHOA, DEPTOR, FKBP11, RGS16 and GPI. EZH2 was recruited to these genes promoters via MTA2 (metastasis associated 1 family, member 2), a component of the nucleosome remodeling and histone deacetylase (NuRD) complex. MTA2 was identified as a new chromatin binding protein whose association with chromatin facilitated the subsequent recruitment of EZH2 to silenced targeted genes, especially TSC2. Downregulation of TSC2 (tuberous sclerosis 2) by EZH2 elicited MTOR activation, which in turn modulated subsequent MTOR pathway-related events, including inhibition of autophagy. In human colorectal carcinoma (CRC) tissues, the expression of MTA2 and EZH2 correlated negatively with expression of TSC2, which reveals a novel link among epigenetic regulation, the MTOR pathway, autophagy induction, and tumorigenesis. 相似文献
994.
Microbulbifer hainanensis sp. nov., a moderately halopilic bacterium isolated from mangrove sediment
Cheng Yuping Zhu Suting Guo Chaobo Xie Feilu Jung Dawoon Li Shengying Zhang Weiyan He Shan 《Antonie van Leeuwenhoek》2021,114(7):1033-1042
Antonie van Leeuwenhoek - A new bacterium was successfully isolated from a mangrove sediment sample in Haikou City, Hainan Province, China. The organism is a Gram-negative, rod-shaped, non-motile... 相似文献
995.
Manon M. S. Richard Stéphanie Pflieger Mireille Sévignac Vincent Thareau Sophie Blanchet Yupeng Li Scott A. Jackson Valérie Geffroy 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(7):1653-1666
Key message
The Co - x anthracnose R gene of common bean was fine-mapped into a 58 kb region at one end of chromosome 1, where no canonical NB-LRR-encoding genes are present in G19833 genome sequence.Abstract
Anthracnose, caused by the phytopathogenic fungus Colletotrichum lindemuthianum, is one of the most damaging diseases of common bean, Phaseolus vulgaris. Various resistance (R) genes, named Co-, conferring race-specific resistance to different strains of C. lindemuthianum have been identified. The Andean cultivar JaloEEP558 was reported to carry Co-x on chromosome 1, conferring resistance to the highly virulent strain 100. To fine map Co-x, 181 recombinant inbred lines derived from the cross between JaloEEP558 and BAT93 were genotyped with polymerase chain reaction (PCR)-based markers developed using the genome sequence of the Andean genotype G19833. Analysis of RILs carrying key recombination events positioned Co-x at one end of chromosome 1 to a 58 kb region of the G19833 genome sequence. Annotation of this target region revealed eight genes: three phosphoinositide-specific phospholipases C (PI-PLC), one zinc finger protein and four kinases, suggesting that Co-x is not a classical nucleotide-binding leucine-rich encoding gene. In addition, we identified and characterized the seven members of common bean PI-PLC gene family distributed into two clusters located at the ends of chromosomes 1 and 8. Co-x is not a member of Co-1 allelic series since these two genes are separated by at least 190 kb. Comparative analysis between soybean and common bean revealed that the Co-x syntenic region, located at one end of Glycine max chromosome 18, carries Rhg1, a major QTL contributing to soybean cyst nematode resistance. The PCR-based markers generated in this study should be useful in marker-assisted selection for pyramiding Co-x with other R genes. 相似文献996.
997.
<正>弄岗国家级自然保护区地处云贵高原向东南倾斜的前缘缓冲地带,位于广西的西南部,跨龙州、宁明两县,地理坐标为106°42′28″–107°4′54″E,22°13′56″–22°33′9″N之间,由陇呼、弄岗及陇山3个片区组成,总面积约101 km2。弄岗保护区属典型的喀斯特石山地貌,是我国热带北缘岩溶森林生态系统的典型代表。该区是热带季风气候,年平均降雨量1,350 mm,有明显的旱季和雨季,降雨量主要集中在5–9月(广西壮族自治区林业厅,1993),海拔 相似文献
998.
Objective
The aim of this study was to detect the effects of varying tissue sizes on the efficiency of baboon ovarian tissue vitrification.Study design
The percentages of morphologically normal primordial follicles and the follicles expressing bax protein in ovarian tissues after vitrification–warming were measured. Besides, the 17-β estradiol levels in the culture supernatants were measured.Results
The percentages of morphologically normal primordial follicles in vitrified–warmed ovarian tissues slicing in 0.5–1.5 mm in length and wide, and 1.0 mm in thickness were significantly higher than those slicing in 2.0 mm in length and wide, and 1.0 mm in thickness. Moreover, the follicles expressing bax protein in vitrified–warmed ovarian tissues slicing in 0.5–1.5 mm in length and wide, and 1.0 mm in thickness were significantly lower than those slicing in 2.0 mm in length and wide, and 1.0 mm in thickness. The 17-β estradiol levels in the culture supernatants slicing in 1.0–1.5 mm in length and wide, and 1.0 mm in thickness were significantly higher than those slicing in 0.5 mm or 2.0 mm in length and wide, and 1.0 mm in thickness.Conclusions
Cortex piece slicing in 1.0–1.5 mm in length and wide, and 1.0 mm in thickness is suitable for baboon ovarian vitrification. 相似文献999.
Guangyuan Li Isaac N. Hayward Brittany R. Jenkins Heather M. Rothfuss Coleman H. Young Marja T. Nevalainen Aaron Muth Paul R. Thompson Amy M. Navratil Brian D. Cherrington 《PloS one》2016,11(1)
Peptidylarginine deiminases (PADs) post-translationally convert arginine into neutral citrulline residues. Our past work shows that PADs are expressed in the canine and murine mammary glands; however, the mechanisms regulating PAD expression and the function of citrullination in the normal mammary gland are unclear. Therefore, the first objective herein was to investigate regulation of PAD expression in mammary epithelial cells. We first examined PAD levels in CID-9 cells, which were derived from the mammary gland of mid-pregnant mice. PAD3 expression is significantly higher than all other PAD isoforms and mediates protein citrullination in CID-9 cells. We next hypothesized that prolactin regulates PAD3 expression. To test this, CID-9 cells were stimulated with 5 μg/mL of prolactin for 48 hours which significantly increases PAD3 mRNA and protein expression. Use of a JAK2 inhibitor and a dominant negative (DN)-STAT5 adenovirus indicate that prolactin stimulation of PAD3 expression is mediated by the JAK2/STAT5 signaling pathway in CID-9 cells. In addition, the human PAD3 gene promoter is prolactin responsive in CID-9 cells. Our second objective was to investigate the expression and activity of PAD3 in the lactating mouse mammary gland. PAD3 expression in the mammary gland is highest on lactation day 9 and coincident with citrullinated proteins such as histones. Use of the PAD3 specific inhibitor, Cl4-amidine, indicates that PAD3, in part, can citrullinate proteins in L9 mammary glands. Collectively, our results show that upregulation of PAD3 is mediated by prolactin induction of the JAK2/STAT5 signaling pathway, and that PAD3 appears to citrullinate proteins during lactation. 相似文献
1000.