Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.7.6 (RNA polymerase)
 34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Infectivity of human T-lymphotropic virus type I (HTLV-I) to human nervous tissue cells was explored using co-cultivation with X-irradiated, HTLV-I-producing MT2 cells. Examined cells included normal cerebellar cells, brain tumor cells (astrocytoma, medulloblastoma, meningioma, hemangioblastoma, and schwannoma), and various cell lines (astrocytoma, ependymoma, oligodendroglioma, medulloblastoma, and neuroblastoma). Successful HTLV-I infection was confirmed immunohistochemically using monoclonal antibodies to HTLV-I p19, p24, and pX product. All cell lines and primary cultures from normal cerebellar tissues and brain tumors could be infected with HTLV-I. Double immunostaining showed that glial fibrillary acidic protein-, S-100 protein- or vimentin-positive cells were susceptible to infection. Neurofilament- or neuron-specific enolase-positive cells in medulloblastoma could also be infected. Reverse-transcriptase assay revealed the productive infection in U251-MG (astrocytoma) and KG-IC (oligodendroglioma) lines. Co-cultivated U251-MG cells formed syncytial polykaryons after serial passages, and polymerase chain reaction assay detected HTLV-I genome in U251-MG syncytial polykaryons and p19+ mononuclear cells. HTLV-I viral RNA was also detected in infected U251-MG cells by in situ hybridization. These data show that HTLV-I may have a wide spectrum of infectivity in human nervous tissues.
 ...
PMID:Infectivity of human T-lymphotropic virus type I to human nervous tissue cells in vitro. 138 59

Germline mutations in the von Hippel-Lindau tumor suppressor gene (VHL) predispose individuals to a variety of tumors, including renal carcinoma, hemangioblastoma of the central nervous system, and pheochromocytoma. Here, a cellular transcription factor, Elongin (SIII), is identified as a functional target of the VHL protein. Elongin (SIII) is a heterotrimer consisting of a transcriptionally active subunit (A) and two regulatory subunits (B and C) that activate transcription elongation by RNA polymerase II. The VHL protein was shown to bind tightly and specifically to the Elongin B and C subunits and to inhibit Elongin (SIII) transcriptional activity in vitro. These findings reveal a potentially important transcriptional regulatory network in which the VHL protein may play a key role.
 ...
PMID:Inhibition of transcription elongation by the VHL tumor suppressor protein. 766 Jan 21

Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder that predisposes the affected individual to develop characteristic tumors. These include CNS hemangioblastoma, retinal angiomas, endolymphatic sac tumors, pancreatic cysts and tumors, epididymal cystadenomas, pheochromocytomas, renal cysts, and clear-cell renal carcinoma. The VHL gene was localized to 3p25 and then isolated by Latif et al. (1). The gene contains three exons with an open reading frame of 852 nucleotides, which encode a predicted protein of 284 amino acids. The VHL protein is believed to have several functions. It is involved in transcription regulation through its inhibition of elongation by binding to the B and C subunits of elongin. Mutations of VHL allow the B and C subunits to bind with the A subunit. This complex then overcomes "pausing" of RNA polymerase during mRNA transcription (2,3). Several studies suggest that the VHL protein is also involved in regulation of hypoxia-inducible transcripts, particularly vascular endothelial growth factor (VEGF), by altering mRNA stability (4,5). Therefore, VHL gene mutations permit the overexpression of VEGF under normoxic conditions, which leads to the angiogenesis believed to be required for tumor growth. The VHL-elongin BC complex (VBC) also binds two other proteins-CUL2 and Rbx1-in a complex that has structural similarity to other E3 ubiquitin ligase complexes (6). Such complexes mediate the degradation of cell-cycle regulatory proteins.
 ...
PMID:Molecular analysis of the von hippel-lindau disease gene. 2131 97