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621.
Shikui Tu Monica Z. Wu Jie Wang Asher D. Cutter Zhiping Weng Julie M. Claycomb 《Nucleic acids research》2015,43(1):208-224
As a champion of small RNA research for two decades, Caenorhabditis elegans has revealed the essential Argonaute CSR-1 to play key nuclear roles in modulating chromatin, chromosome segregation and germline gene expression via 22G-small RNAs. Despite CSR-1 being preserved among diverse nematodes, the conservation and divergence in function of the targets of small RNA pathways remains poorly resolved. Here we apply comparative functional genomic analysis between C. elegans and Caenorhabditis briggsae to characterize the CSR-1 pathway, its targets and their evolution. C. briggsae CSR-1-associated small RNAs that we identified by immunoprecipitation-small RNA sequencing overlap with 22G-RNAs depleted in cbr-csr-1 RNAi-treated worms. By comparing 22G-RNAs and target genes between species, we defined a set of CSR-1 target genes with conserved germline expression, enrichment in operons and more slowly evolving coding sequences than other genes, along with a small group of evolutionarily labile targets. We demonstrate that the association of CSR-1 with chromatin is preserved, and show that depletion of cbr-csr-1 leads to chromosome segregation defects and embryonic lethality. This first comparative characterization of a small RNA pathway in Caenorhabditis establishes a conserved nuclear role for CSR-1 and highlights its key role in germline gene regulation across multiple animal species. 相似文献
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The construct General Sleep-related Experiences (GSEs, such as elevated dream recall, vivid or bizarre dreams, flying dreams, hypnagogic hallucinations, nightmares, and recurrent dreams) has been previously linked to various forms of psychopathology in nonclinical populations. The aim of this pilot study was to explore this relationship in the context of severe psychopathology. Nineteen outpatients of a mental health clinic were compared to 26 controls on sleep experiences, psychopathology, sleep quality, life stress, and transliminality. Outpatients also reported illness intrusiveness levels. As expected, the outpatient group had elevated GSEs. Within the outpatient group, illness intrusiveness, stress, and transliminality were correlated with GSEs. These findings elucidate the association between GSEs and distress in the context of severe psychopathology. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Sarah W. Zangen Pirhiya Yaffe Svetlana Shechtman David H. Zangen Asher Ornoy 《Experimental diabetes research》2002,3(4):247-255
The role of the antioxidant defense mechanism in diabetesinduced
anomalies was studied in the Cohen diabetes-sensitive
(CDs) and -resistant (CDr) rats, a genetic model of nutritionally
induced type 2 diabetes mellitus. Embryos, 12.5-day-old, of CDs
and CDr rats fed regular diet (RD) or a diabetogenic high-sucrose
diet (HSD) were monitored for growth retardation and congenital
anomalies. Activity of superoxide dismutase (SOD) and catalaselike
enzymes and levels of ascorbic acid (AA), uric acid (UA), and
dehydroascorbic acid (DHAA) were measured in embryonic homogenates.
When fed RD, CDs rats had a decreased rate of pregnancy,
and an increased embryonic resorption. CDs embryos were
smaller than CDr embryos; 46% were maldeveloped and 7% exhibited
neural tube defects (NTDs). When fed HSD, rate of pregnancy
was reduced, resorption rate was greatly increased (56%;
P < .001), 47.6% of the embryos were retrieved without heart
beats, and 27% exhibited NTD. In contrast, all the CDr embryos
were normal when fed RD or HSD. Activity of SOD and catalase
was not different in embryos of CDs and CDr rats fedRD. When fed
HSD, levels of AA were significantly reduced, the ratio DHAA/AA
was significantly increased, and SOD activity was not sufficiently
increased when compared to embryos of CDr. The reduced fertility
of the CDs rats, the growth retardation, and NTD seem to be
genetically determined. Maternal hyperglycemia seems to result in environmentally induced embryonic oxidative stress, resulting in
further embryonic damage. 相似文献