Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Astrocytes have a critical role in the neuronal response to ischemia, as their production of neurotrophic mediators can favorably impact on the extreme sensitivity of nervous tissue to oxygen deprivation. Using a differential display method, a novel putative RNA binding protein, RA301, was cloned from reoxygenated astrocytes. Analysis of the deduced amino acid sequence showed two ribonucleoprotein domains and serine/arginine-rich domains, suggestive of their function as RNA splicing factor. Northern analysis displayed striking induction only in cultured astrocytes within 15 min of reoxygenation and reached a maximum by 60 min after hypoxia/reoxygenation. Immunoblotting demonstrated expression of an immunoreactive polypeptide of the expected molecular mass, 36 kDa, in lysates of hypoxia/reoxygenated astrocytes. Induction of RA301 mRNA was mediated, in large part, by endogenously generated reactive oxygen species, as shown by diphenyl iodonium, an inhibitor of neutrophil-type nicotinamide adenine dinucleotide phosphate oxidase which blocks oxygen-free radical formation by astrocytes. Similarly, increased expression of RA301 in supporting a neurotrophic function of astrocytes was suggested by inhibition of interleukin-6 elaboration, a neuroprotective cytokine, in the presence of antisense oligonucleotide for RA301. These studies provide a first step in characterizing a novel putative RNA binding protein, whose expression is induced by oxygen-free radicals generated during hypoxia/reoxygenation, and which may have an important role in redirection of biosynthetic events observed in the ischemic tissues.
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PMID:Cloning of a novel RNA binding polypeptide (RA301) induced by hypoxia/reoxygenation. 749 16

To elucidate the role of astrocytes in the stress response of the central nervous system to ischemia, early gene expression was examined in rat cultured astrocytes after the exposure to hypoxia/reoxygenation, and we have previously cloned a novel RNA binding protein, RA301, from the reoxygenated astrocytes. Furthermore, we have now cloned a new gene for RA301 binding protein, termed YT521, by a yeast two-hybrid screening technique to explore RA301 functions. The YT521 cDNA is about 3200 bp long with an open reading frame encoding 712 amino acids. This amino acid sequence contains arginine-aspartic acid-glutamic acid rich region and glutamic acid rich one, and has a low degree of homology with RNA binding proteins such as U1-70k. Northern blot analysis revealed that YT521 mRNA expression was up-regulated in reoxygenated astrocytes. Induction of YT521 mRNA was mediated by endogenously generated reactive oxygen species, as it was suppressed by treatment of the cells with diphenyl iodonium which blocks oxygen-free radical formation by astrocytes. These expression patterns resembled those of RA301 mRNA. Far Western blot analysis showed that YT521 protein was not only interacting with RA301 protein, but also with SC35 and SF2, both of which are splicing factors. These results suggest that YT521 is a novel candidate for RNA splicing-related protein.
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PMID:Cloning of a gene, YT521, for a novel RNA splicing-related protein induced by hypoxia/reoxygenation. 947 74