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)

The e(y)2 gene of Drosophila melanogaster encodes the ubiquitous evolutionarily conserved co-activator of RNA polymerase II that is involved in transcription regulation of a high number of genes. The Drosophila e(y)2b gene, paralogue of the e(y)2 has been found. The analysis of structure of the e(y)2, e(y)2b and its orthologues from other species reveals that the e(y)2 gene derived as a result of retroposition of the e(y)2b during Drosophila evolution. The mRNA-derived retrogenes lack introns or regulatory regions; most of them become pseudogenes whereas some acquire tissue-specific functions. Here we describe the different situation: the e(y)2 retrogene performs the general function and is ubiquitously expressed, while the source gene is functional only in a small group of male germ cells. This must have resulted from retroposition into a transcriptionally favorable region of the genome.
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PMID:A retrocopy of a gene can functionally displace the source gene in evolution. 1631 24

Transcriptional activators, several different coactivators, and general transcription factors are necessary to access specific loci in the dense chromatin structure to allow precise initiation of RNA polymerase II (Pol II) transcription. Histone acetyltransferase (HAT) complexes were implicated in loosening the chromatin around promoters and thus in gene activation. Here we demonstrate that the 2 MDa GCN5 HAT-containing metazoan TFTC/STAGA complexes contain a histone H2A and H2B deubiquitinase activity. We have identified three additional subunits of TFTC/STAGA (ATXN7L3, USP22, and ENY2) that form the deubiquitination module. Importantly, we found that this module is an enhancer of position effect variegation in Drosophila. Furthermore, we demonstrate that ATXN7L3, USP22, and ENY2 are required as cofactors for the full transcriptional activity by nuclear receptors. Thus, the deubiquitinase activity of the TFTC/STAGA HAT complex is necessary to counteract heterochromatin silencing and acts as a positive cofactor for activation by nuclear receptors in vivo.
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PMID:A TFTC/STAGA module mediates histone H2A and H2B deubiquitination, coactivates nuclear receptors, and counteracts heterochromatin silencing. 1824 9

Metazoan E(y)2/ENY2 is a multifunctional protein important for transcription activation and mRNA export, being a component of SAGA/TFTC and the mRNA export complex AMEX. Here, we show that ENY2 in Drosophila is also stably associated with THO, the complex involved in mRNP biogenesis. The ENY2-THO complex is required for normal Drosophila development, functioning independently on SAGA and AMEX. ENY2 and THO arrive on the transcribed region of the hsp70 gene after its activation, and ENY2 plays an important role in THO recruitment. ENY2 and THO show no direct association with elongating RNA polymerase II. Recruitment of ENY2 and THO occurs by their loading onto nascent mRNA, apparently immediately after its synthesis, while the AMEX component Xmas-2 is loaded onto mRNA at a later stage. Knockdown of either ENY2 or THO, but not SAGA or AMEX, affects the processing of the transcript's 3' end. Thus, ENY2, as a shared subunit of several protein complexes governing the sequential steps of gene expression, plays an important role in the coordination of these steps.
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PMID:Multifunctional factor ENY2 is associated with the THO complex and promotes its recruitment onto nascent mRNA. 2004 2

Export of messenger RNA (mRNA) from the nucleus to the cytoplasm is a critical step in the gene expression pathway of eukaryotic cells. Here, we report the functional and structural characterization of the mammalian TREX-2 complex and show how it links transcription/processing with nuclear mRNA export. Mammalian TREX-2 is based on a germinal-centre associated nuclear protein (GANP) scaffold to which ENY2, PCID2 and centrins bind and depletion of any of these components inhibits mRNA export. The crystal structure of the GANP:ENY2 complex shows that two ENY2 chains interact directly with GANP, but they have different orientations from those observed on yeast Sac3. GANP is required to recruit ENY2 to nuclear pore complexes (NPCs), but ENY2 is not necessary to recruit GANP, which requires both its CID and MCM3AP domains, together with nucleoporin Nup153. GANP and ENY2 associate with RNA polymerase II and inhibition of mRNA processing redistributes GANP from NPCs into nuclear foci indicating that mammalian TREX-2 is associated with transcription. Thus, we implicate TREX-2 as an integral component of the mammalian mRNA export machinery where it links transcription and nuclear export by facilitating the transfer of mature mRNPs from the nuclear interior to NPCs.
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PMID:Functional and structural characterization of the mammalian TREX-2 complex that links transcription with nuclear messenger RNA export. 2230 88