Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q9UIJ5 (Rec)
 58,342 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Direct localization of specific genes, RNAs, and proteins has allowed the dissection of individual nuclear speckles in relation to the molecular biology of gene expression. Nuclear speckles (aka SC35 domains) are essentially ubiquitous structures enriched for most pre-mRNA metabolic factors, yet their relationship to gene expression has been poorly understood. Analyses of specific genes and their spliced or mature mRNA strongly support that SC35 domains are hubs of activity, not stores of inert factors detached from gene expression. We propose that SC35 domains are hubs that spatially link expression of specific pre-mRNAs to rapid recycling of copious RNA metabolic complexes, thereby facilitating expression of many highly active genes. In addition to increasing the efficiency of each step, sequential steps in gene expression are structurally integrated at each SC35 domain, consistent with other evidence that the biochemical machineries for transcription, splicing, and mRNA export are coupled. Transcription and splicing are subcompartmentalized at the periphery, with largely spliced mRNA entering the domain prior to export. In addition, new findings presented here begin to illuminate the structural underpinnings of a speckle by defining specific perturbations of phosphorylation that promote disassembly or assembly of an SC35 domain in relation to other components. Results thus far are consistent with the SC35 spliceosome assembly factor as an integral structural component. Conditions that disperse SC35 also disperse poly(A) RNA, whereas the splicing factor ASF/SF2 can be dispersed under conditions in which SC35 or SRm300 remain as intact components of a core domain.
Anat Rec A Discov Mol Cell Evol Biol 2006 Jul
PMID:Molecular anatomy of a speckle. 1676 Dec 80

Nuclear speckles, which are sites of pre-mRNA splicing and/or assembly components, are diffusely distributed throughout the nucleoplasm. They are composed of splicing factors (SFs), including SC-35, which are nuclear proteins that remove introns (noncoding sequences in the genes) from precursor mRNA molecules, to form mature RNA, which will be transported to the cytoplasm, site of protein synthesis and activation. In light of such evidences, here we report that hypoxia modulates in vivo SC-35 SF phosphorylation via protein kinase C (PKC) delta in young rat heart. Trichrome Mallory staining and TUNEL analysis along with immunohistochemistry and Western blotting have been performed on left ventricles excised from young and old rats exposed to intermittent hypoxia. Although young hypoxic myocardial cells appear smaller than normoxic cells, connective and endothelial components increase, SC-35 phosphorylation is particularly evident in the endothelium and paralleled by an increased expression of vascular endothelial growth factor (VEGF). In addition, SC-35 and PKC delta coimmunoprecipitation occurs, suggesting that SC-35 phosphorylation could be PKC delta-mediated and that hypoxic young heart needs to counteract the damage through a process of neoangiogenesis involving such SF. Even though the levels of SC-35 and PKC delta are high, the similar response disclosed by normoxic and hypoxic old rat hearts (both showing a fibrotic organization, similar endothelial components and VEGF levels) could be due to the existence of an impaired oxygen sensing mechanism and thus to a low rate of angiogenesis.
Anat Rec (Hoboken) 2009 Aug
PMID:Effect of hypoxia and aging on PKC delta-mediated SC-35 phosphorylation in rat myocardial tissue. 1964 17