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41.
Tao Zhong Jianmei Zhang Xiaoying Han Xiaoxiao Gongye Tianqi Lyu Menghan Jiang Kaiwei Yu Xiaoqian Meng Dong Cheng Hui Lyu Tianliang Zhang Lei Zhang Shuzhen Liu 《Journal of cellular biochemistry》2019,120(9):15337-15346
3,3′,4,4′,5-Polychlorinated biphenyl (PCB126) is a persistent organic environmental pollutant which can affect various biological activities of organisms, such as immunity, neurological function, and reproduction. In our study, we aimed to investigate the effects of PCB126 on granulosa cells (GCs). GCs were collected from ovaries in PMSG-treated mice, after 24 hours culture. GCs were then incubated with 10 pg/mL, 100 pg/mL, and 10 ng/mL of PCB126 for another 24 hours. Following these steps, exposed GCs were collected for further experimentation. Our data showed that the number of GCs in the 10 ng/mL PCB126 decreased. Meanwhile, pyknotic nuclei and condensed chromatin increased, while the apoptotic cells in the 10 ng/mL PCB126 group were significantly increased. Furthermore, the expression of the apoptotic executive protein caspase-3 increased after PCB126 treatment. The expression of Bax, Bcl-2, and Bim related to the mitochondrial apoptosis pathway were also influenced to different degrees. Thus, our data suggested that PCB126 affect the GCs apoptosis, and mitochondrial apoptosis pathway was involved in this process. 相似文献
42.
Receptor-mediated interference mechanism responsible for resistance to polytropic leukemia viruses in Mus castaneus
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The Asian mouse Mus castaneus is resistant to infection by the polytropic mink cell focus-inducing (MCF) subgroup of murine leukemia viruses (MuLVs). Genetic crosses showed this recessive resistance to be governed by a single gene that maps at or near the gene encoding the polytropic viral receptor, Rmc1. To investigate this resistance, we mated M. castaneus with mice carrying the wild mouse Sxv variant of the Rmc1 receptor that allows infection by xenotropic as well as polytropic virus. Unlike other F1 hybrids of M. castaneus, these F1 mice were resistant to both xenotropic and polytropic classes of MuLVs. Analysis of backcrossed progeny of the F1 hybrids mated to Sxv mice indicates that resistance is due to inheritance of two M. castaneus genes. Cells from individual backcross mice were also examined for cell surface antigen by fluorescence-activated cell sorter analysis with monoclonal antibodies reactive with xenotropic or MCF virus env glycoproteins. A correlation was observed between virus resistance and antigen, suggesting that virus resistance is due to expression of endogenous viral envelope genes that interfere with infection by exogenous virus. Since the inbred strain Rmc1 receptor remains functional in the presence of these M. castaneus genes, and since M. castaneus contains multiple copies of xenotropic MuLV env genes, we suggest that these resistance genes control expression of xenotropic env glycoprotein that interferes with exogenous virus in cells containing the Sxv variant of Rmc1. 相似文献
43.
Dong C Lyu SC Krensky AM Clayberger C 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(10):5064-5070
DQ 65-79, a peptide derived from residues 65-79 of the alpha-chain HLA class II molecule DQA03011, blocks T cell proliferation and induces T cell apoptosis. Using a yeast two-hybrid assay, we previously identified proliferating cell nuclear Ag (PCNA) as an intracellular ligand for DQ 65-79. In this study, we show that three regions of PCNA, residues 81-100, 121-140, and 241-261, interact with DQ 65-79. Residues 241-261 of PCNA also interact with the C terminus (residues 139-160) of the cell cycle regulator, p21, suggesting that DQ 65-79 and p21 might function similarly. We show here that DQ 65-79 competitively inhibits binding of p21 to PCNA and that both DQ 65-79 and p21 139-160 induce T cell apoptosis, suggesting that DQ 65-79 and p21 act similarly to inhibit cell growth. 相似文献
44.
45.
Characterization of a polytropic murine leukemia virus proviral sequence associated with the virus resistance gene Rmcf of DBA/2 mice
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The DBA/2 mouse Rmcf gene is responsible for in vivo and in vitro resistance to infection by the polytropic mink cell focus-forming (MCF) virus subgroup of murine leukemia viruses (MLVs). Previous studies suggested that Rmcf resistance is mediated by expression of an interfering MCF MLV envelope (Env) gene. To characterize this env gene, we examined resistance in crosses between Rmcf(r) DBA/2 mice and Mus castaneus, a species that lacks endogenous MCF env sequences. In backcross progeny, inheritance of Rmcf resistance correlated with inheritance of a specific endogenous MCF virus env-containing 4.6-kb EcoRI fragment. This fragment was present in the DBA/2N substrain with Rmcf-mediated resistance but not in virus-susceptible DBA/2J substrain mice. This fragment contains a provirus with a 5' long terminal repeat and the 5' half of env; the gag and pol genes have been partially deleted. The Env sequence is identical to that of a highly immunogenic viral glycoprotein expressed in the DBA/2 cell line L5178Y and closely resembles the env genes of modified polytropic proviruses. The coding sequence for the full-length Rmcf Env surface subunit was amplified from DNAs from virus-resistant backcross mice and was cloned into an expression vector. NIH 3T3 and BALB 3T3 cells stably transfected with this construct showed significant resistance to infection by MCF MLV but not by amphotropic MLV. This study identifies an Rmcf-linked MCF provirus and indicates that, like the ecotropic virus resistance gene Fv4, Rmcf may mediate resistance through an interference mechanism. 相似文献
46.
Background
Existing cut-offs for fasting plasma glucose (FPG) and post-load glucose (2hPG) criteria are not equivalent in the diagnosis of diabetes and glucose intolerance. Adjusting cut-offs of single measurements have not helped so we undertook this project to see if they could be complementary. 相似文献47.
Purification and characterization of a novel 7-kDa non-specific lipid transfer protein-2 from rice (Oryza sativa) 总被引:1,自引:0,他引:1
Liu YJ Samuel D Lin CH Lyu PC 《Biochemical and biophysical research communications》2002,294(3):535-540
A novel 7-kDa non-specific lipid transfer protein-2 (nsLTP2) has been isolated from rice (Oryza sativa) seeds. In contrast to nsLTP1s, few nsLTP2s have been purified and characterized. Complete amino acid sequence of rice nsLTP2 was determined by N-terminal Edman degradation of the intact protein as well as the peptide fragments resulted from trypsin digestions. Rice nsLTP2 consists of 69 amino acid residues with eight conserved cysteines forming four disulfide bonds. The secondary structure of rice nsLTP2 is predominantly alpha-helical as determined by circular dichroism spectroscopy. Cysteine pairings of nsLTP2 have one miss match at Cys(35)-X-Cys(37) motif compared to nsLTP1. Primary structure analysis of various plant nsLTP2s revealed an interesting conservation of sequence features among nsLTP2 family. 相似文献
48.
Out of Africa and back again: nested cladistic analysis of human Y chromosome variation 总被引:18,自引:3,他引:15
Hammer MF; Karafet T; Rasanayagam A; Wood ET; Altheide TK; Jenkins T; Griffiths RC; Templeton AR; Zegura SL 《Molecular biology and evolution》1998,15(4):427-441
We surveyed nine diallelic polymorphic sites on the Y chromosomes of 1,544
individuals from Africa, Asia, Europe, Oceania, and the New World.
Phylogenetic analyses of these nine sites resulted in a tree for 10
distinct Y haplotypes with a coalescence time of approximately 150,000
years. The 10 haplotypes were unevenly distributed among human populations:
5 were restricted to a particular continent, 2 were shared between Africa
and Europe, 1 was present only in the Old World, and 2 were found in all
geographic regions surveyed. The ancestral haplotype was limited to African
populations. Random permutation procedures revealed statistically
significant patterns of geographical structuring of this paternal genetic
variation. The results of a nested cladistic analysis indicated that these
geographical associations arose through a combination of processes,
including restricted, recurrent gene flow (isolation by distance) and range
expansions. We inferred that one of the oldest events in the nested
cladistic analysis was a range expansion out of Africa which resulted in
the complete replacement of Y chromosomes throughout the Old World, a
finding consistent with many versions of the Out of Africa Replacement
Model. A second and more recent range expansion brought Asian Y chromosomes
back to Africa without replacing the indigenous African male gene pool.
Thus, the previously observed high levels of Y chromosomal genetic
diversity in Africa may be due in part to bidirectional population
movements. Finally, a comparison of our results with those from nested
cladistic analyses of human mtDNA and beta-globin data revealed different
patterns of inferences for males and females concerning the relative roles
of population history (range expansions) and population structure
(recurrent gene flow), thereby adding a new sex-specific component to
models of human evolution.
相似文献
49.
Ying Lyu Xueying Su Jingna Deng Shangxin Liu Liangqiang Zou Xiaojing Zhao Suning Wei Bin Geng Guoheng Xu 《PloS one》2015,10(2)
Perilipin 1 (Plin1) localizes at the surface of lipid droplets to regulate triglyceride storage and hydrolysis in adipocytes. Plin1 defect leads to low adiposity in mice and partial lipodystrophy in human. This study investigated the roles of Plin1 in adipocyte differentiation. Plin1 null (-/-) mice showed plenty of multilocular adipocytes and small unilocular adipocytes in adipose tissue, along with lack of a subpopulation of adipose progenitor cells capable of in vivo adipogenesis and along with downregulation of adipogenic pathway. Before initiation of differentiation, adipose stromal-vascular cells (SVCs) from Plin1-/- mice already accumulated numerous tiny lipid droplets, which increased in number and size during the first 12-h induction but thereafter became disappeared at day 1 of differentiation. The adipogenic signaling was dysregulated despite protein level of PPARγ was near normal in Plin1-/- SVCs like in Plin1-/- adipose tissue. Heterozygous Plin1+/- SVCs were able to develop lipid droplets, with both the number and size more than in Plin1-/- SVCs but less than in Plin1+/+ SVCs, indicating that Plin1 haploinsufficiency accounts for attenuated adipogenesis. Aberrant lipid droplet growth and differentiation of Plin1-/- SVCs were rescued by adenoviral Plin1 expression and were ameliorated by enhanced or prolonged adipogenic stimulation. Our finding suggests that Plin1 plays an important role in adipocyte differentiation and provides an insight into the pathology of partial lipodystrophy in patients with Plin1 mutation. 相似文献
50.
Xiaofei Lyu Junbao Yu Mo Zhou Bin Ma Guangmei Wang Chao Zhan Guangxuan Han Bo Guan Huifeng Wu Yunzhao Li De Wang 《PloS one》2015,10(3)