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RNA Functions (rna + function)
Selected AbstractsRNA damage and surveillance under oxidative stressIUBMB LIFE, Issue 10 2006Zhongwei Li Abstract RNA damage has been recently reported to increase under oxidative stress and in patients with many degenerative diseases, which has drawn attention to the consequences of RNA oxidation at the molecular and cellular levels. Under similar conditions the levels of oxidative damage in RNA are usually higher than those in DNA, which may impair protein synthesis or other RNA function. Therefore, accumulation of RNA damage must be prevented and cells have developed specific mechanisms to remove oxidatively-damaged RNA and to block incorporation of oxidized nucleotides during RNA synthesis. Removal of oxidized RNA may be mediated by specific proteins that recognize oxidative lesions and direct the RNA degradation machinery to eliminate the damaged RNAs. During RNA synthesis, oxidized ribonucleotides are hydrolyzed or discriminated from normal ribonucleotides during transcription, preventing their incorporation into RNA. Collective evidence suggests that RNA oxidative damage is a challenging and persistent problem normally controlled through RNA surveillance mechanisms, making them critical to maintaining cellular health and preventing disease. iubmb Life, 58: 581-588, 2006 [source] Maternal expression and function of the Drosophila sox gene Dichaete during oogenesisDEVELOPMENTAL DYNAMICS, Issue 10 2006Ashim Mukherjee Abstract Members of the Sox family of DNA-binding HMG domain proteins have been shown to regulate gene transcription in a wide range of developmental processes, including sex determination, neurogenesis, and chondrogenesis. However, little is known about their potential functions in developing germline tissues. In Drosophila, the Sox protein Dichaete (a.k.a., Fish-hook) is a member of the SoxB subgroup whose HMG domain shares strong sequence similarity to that of vertebrate Sox2. Dichaete exhibits dynamic expression in embryonic and larval stages and has pleiotropic functions in a variety of tissues. In this study, we extend analyses of Dichaete function and show that expression of Dichaete protein is detected in the developing oocyte during early to mid stages of oogenesis. Strikingly, Dichaete exhibits cytoplasmic distribution and is not detected in the oocyte nucleus. Germline mosaic analyses revealed that the Dichaete gene has maternal functions that influence dorsal/ventral patterning of the egg chamber. Dichaete mutant eggs exhibit defects in formation of the dorsal appendages, differentiation of dorsal/anterior follicle cells, and mislocalization of Gurken protein and gurken mRNA. Dichaete protein was shown to possess RNA-binding capabilities, suggesting a direct post-transcriptional role in regulating RNA functions. Developmental Dynamics 235:2828,2835, 2006. © 2006 Wiley-Liss, Inc. [source] Functional association of human Ki-1/57 with pre-mRNA splicing eventsFEBS JOURNAL, Issue 14 2009Gustavo C. Bressan The cytoplasmic and nuclear protein Ki-1/57 was first identified in malignant cells from Hodgkin's lymphoma. Despite studies showing its phosphorylation, arginine methylation, and interaction with several regulatory proteins, the functional role of Ki-1/57 in human cells remains to be determined. Here, we investigated the relationship of Ki-1/57 with RNA functions. Through immunoprecipitation assays, we verified the association of Ki-1/57 with the endogenous splicing proteins hnRNPQ and SFRS9 in HeLa cell extracts. We also found that recombinant Ki-1/57 was able to bind to a poly-U RNA probe in electrophoretic mobility shift assays. In a classic splicing test, we showed that Ki-1/57 can modify the splicing site selection of the adenoviral E1A minigene in a dose-dependent manner. Further confocal and fluorescence microscopy analysis revealed the localization of enhanced green fluorescent protein,Ki-1/57 to nuclear bodies involved in RNA processing and or small nuclear ribonucleoprotein assembly, depending on the cellular methylation status and its N-terminal region. In summary, our findings suggest that Ki-1/57 is probably involved in cellular events related to RNA functions, such as pre-mRNA splicing. Structured digital abstract ,,MINT-7041074: Ki-1/57 (uniprotkb:Q5JVS0) physically interacts (MI:0915) with SF2P32 (uniprotkb:Q07021) by two hybrid (MI:0018) ,,MINT-7041232: Ki-1/57 (uniprotkb:Q5JVS0) physically interacts (MI:0915) with SFRS9 (uniprotkb:Q13242) by pull down (MI:0096) ,,MINT-7041203: P80-Coilin (uniprotkb:P38432) and Ki-1/57 (uniprotkb:Q5JVS0) colocalize (MI:0403) by fluorescence microscopy (MI:0416) ,,MINT-7041217: SMN (uniprotkb:Q16637) and Ki-1/57 (uniprotkb:Q5JVS0) colocalize (MI:0403) by fluorescence microscopy (MI:0416) ,,MINT-7041189: SC-35 (uniprotkb:Q01130) and Ki-1/57 (uniprotkb:Q5JVS0) colocalize (MI:0403) by fluorescence microscopy (MI:0416) ,,MINT-7041169: NPM (uniprotkb:P06748) and Ki-1/57 (uniprotkb:Q5JVS0) colocalize (MI:0403) by fluorescence microscopy (MI:0416) ,,MINT-7041249: Ki-1/57 (uniprotkb:Q5JVS0) physically interacts (MI:0915) with SFRS9 (uniprotkb:O60506) by pull down (MI:0096) ,,MINT-7041065: Ki-1/57 (uniprotkb:Q5JVS0) physically interacts (MI:0915) with SFRS9 (uniprotkb:Q13242) by two hybrid (MI:0018) ,,MINT-7041069: Ki-1/57 (uniprotkb:Q5JVS0) physically interacts (MI:0915) with YB1 (uniprotkb:P67809) by two hybrid (MI:0018) ,,MINT-7041079: Ki-1/57 (uniprotkb:Q5JVS0) physically interacts (MI:0915) with HNRPQ (uniprotkb:O60506) by two hybrid (MI:0018) ,,MINT-7041087: Ki-1/57 (uniprotkb:Q5JVS0) physically interacts (MI:0218) with HNRPQ3 (uniprotkb:O60506-1), HNRPQ2 (uniprotkb:O60506-2) and HNRPQ-1 (uniprotkb:O60506-3) by anti bait coimmunoprecipitation (MI:0006) [source] Molecular characterization and expression of maternally expressed gene 3 (Meg3/Gtl2) RNA in the mouse inner earJOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2006Shehnaaz S.M. Manji Abstract The pathways responsible for sound perception in the cochlea involve the coordinated and regulated expression of hundreds of genes. By using microarray analysis, we identified several transcripts enriched in the inner ear, including the maternally expressed gene 3 (Meg3/Gtl2), an imprinted noncoding RNA. Real-time PCR analysis demonstrated that Meg3/Gtl2 was highly expressed in the cochlea, brain, and eye. Molecular studies revealed the presence of several Meg3/Gtl2 RNA splice variants in the mouse cochlea, brain, and eye. In situ hybridizations showed intense Meg3/Gtl2 RNA staining in the nuclei of type I spiral ganglion cells and in cerebellum near the dorsal vestibular region of the cochlea. In embryonic mouse head sections, Meg3/Gtl2 RNA expression was observed in the otocyst, brain, eye, cartilage, connective tissue, and muscle. Meg3/Gtl2 RNA expression increased in the developing otocyst and localized to the spiral ganglion, stria vascularis, Reissner's membrane, and greater epithelial ridge (GER) in the cochlear duct. RT-PCR analysis performed on cell lines derived from the organ of Corti, representing neural, supporting, and hair cells, showed significantly elevated levels of Meg3/Gtl2 expression in differentiated neural cells. We propose that Meg3/Gtl2 RNA functions as a noncoding regulatory RNA in the inner ear and that it plays a role in pattern specification and differentiation of cells during otocyst development, as well as in the maintenance of a number of terminally differentiated cochlear cell types. © 2005 Wiley-Liss, Inc. [source] |