Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

After infection of the respective target cells with the human immunodeficiency virus (HIV-1) viral progeny is produced only after a short temporary delay of some days, depending on cell type. After this period of time a sudden onset of HIV-1 protein synthesis with a dramatic increase in virus release occurs. (2'-5')Oligoriboadenylates [(2'-5')A], capable to activate a latent ribonuclease (RNase L) degrading both mRNA and rRNA, are known mediators involved in the early response of cells to virus infection. Here we show that the (2'-5')A-synthesizing (2'-5')A synthetase, which is inducible by interferon and activated by double-stranded RNA, as well as a (2'-5')A nuclease (2',3'-exoribonuclease) are associated with the nuclear matrix of uninfected and infected H9 cells, also in the absence of interferon. Infection of H9 cells with HIV-1 was found to cause a strong (7.7-fold) enhancement of (2'-5')A synthetase activity and a smaller (2-fold) increase of 2',3'-exoribonuclease activity. Simultaneously the concentration of synthesized (2'-5')A increased 5 to 10 times in isolated nuclei. After incubation for 2 to 3 days both enzyme activities reached a maximum and then dropped below their initial values. Concomitantly a drastic increase in virus production occurred, as judged by reverse transcriptase activity in the culture fluid. These results suggest that the (nuclear matrix-associated) (2'-5')A system might be important during the initial stage of HIV infection, also by destructing matrix-bound viral messengers.
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PMID:Alteration of nuclear (2'-5')oligoriboadenylate synthetase and nuclease activities preceding replication of human immunodeficiency virus in H9 cells. 322 94

The deadenylation nuclease or poly(A)-specific ribonuclease (PARN) is a 3' exonuclease, which degrades the poly(A)-tail of eukaryotic mRNA molecules. By DNA sequence analysis of cDNA and genomic clones, fluorescence in situ hybridization, and reverse transcriptase-PCR, we have determined that the active human PARN gene is located in 16p13 and that a truncated copy lacking the 5' end is located in 15q11. The truncated gene maps close to a copy of the D15F37 gene family at the proximal Prader-Willi/Angelman (PWS/AS) deletion breakpoint region. Other copies of the F37 gene family are located at the distal PWS/AS deletion breakpoint region and on 16p11.2. Although PARN and F37 gene sequences are present on 15q and 16p, our data suggest that the synteny of these loci is the result of independent genetic events.
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PMID:The human gene for the poly(A)-specific ribonuclease (PARN) maps to 16p13 and has a truncated copy in the Prader-Willi/Angelman syndrome region on 15q11-->q13. 1064 Aug 32