Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Vpr, an accessory gene of human immunodeficiency virus, induces cell cycle abnormality by accumulating cells at the G2-M phase. We reported recently that Vpr caused both micronuclei formation and aneuploidy. Here, we show that Vpr also induced chromosome breaks and gene amplification. Expression of Vpr induced more than 10-fold increase of colonies resistant to N-(phosphonacetyl)-L-aspartate, an inhibitor of pyrimidine de novo synthesis. Fluorescence in situ hybridization analysis detected that 4 of 10 N-(phosphonacetyl)-L-aspartate resistant clones studied had intrachromosomal amplification of carbamyl-phosphate synthetase/aspartate transcarbamoylase/dihydroorotase gene. Another single clone had dicentrics. Data suggested that the Vpr-induced chromosome breaks leading to gene amplification, followed by bridge-breakage-fusion cycle, were one of the possible mechanisms of Vpr-induced genomic instability.
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PMID:Micronuclei formation with chromosome breaks and gene amplification caused by Vpr, an accessory gene of human immunodeficiency virus. 1034 25

The envelope glycoproteins of the human immunodeficiency virus and the related simian immunodeficiency virus (SIV) mediate viral entry into host cells by fusing viral and target cell membranes. We have reported expression, purification, and characterization of gp140 (also called gp160e), the soluble, trimeric ectodomain of the SIV envelope glycoprotein, gp160 (B. Chen et al., J. Biol. Chem. 275:34946-34953, 2000). We have now expressed and purified chimeric proteins of SIV gp140 and its variants with the catalytic subunit (C) of Escherichia coli aspartate transcarbamoylase (ATCase). The fusion proteins (SIV gp140-ATC) bind viral receptor CD4 and a number of monoclonal antibodies specific for SIV gp140. The chimeric molecule also has ATCase activity, which requires trimerization of the ATCase C chains. Thus, the fusion protein is trimeric. When ATCase regulatory subunit dimers (R(2)) are added, the fusion protein assembles into dimers of trimers as expected from the structure of C(6)R(6) ATCase. Negative-stain electron microscopy reveals spikey features of both SIV gp140 and SIV gp140-ATC. The production of the fusion proteins may enhance the possibilities for structure determination of the envelope glycoprotein either by electron cryomicroscopy or X-ray crystallography.
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PMID:A chimeric protein of simian immunodeficiency virus envelope glycoprotein gp140 and Escherichia coli aspartate transcarbamoylase. 1507 31