Journal Article

Rapid evolution of primate antiviral enzyme APOBEC3G

Jianzhi Zhang and David M. Webb

in Human Molecular Genetics

Volume 13, issue 16, pages 1785-1791
Published in print August 2004 | ISSN: 0964-6906
Published online June 2004 | e-ISSN: 1460-2083 | DOI: http://dx.doi.org/10.1093/hmg/ddh183
Rapid evolution of primate antiviral enzyme APOBEC3G

Show Summary Details

Preview

Human cytidine deaminase APOBEC3G and the virion infectivity factor (vif) of the human immunodeficiency virus (HIV) are a pair of antagonistic molecules. In the absence of vif, APOBEC3G induces a high rate of dC to dU mutations in the nascent reverse transcripts of HIV that leads to the degradation of the HIV genome. HIV vif, on the other hand, can suppress the translation and trigger the degradation of human APOBEC3G. Here, we studied the rate of APOBEC3G gene evolution from five hominoids and two Old World monkeys. Averaged across the entire coding region, the rate of non-synonymous nucleotide substitutions is ∼1.4 times the rate of synonymous substitutions, strongly suggesting that APOBEC3G has been under positive Darwinian selection. A comparison between the nucleotide polymorphisms within humans and the substitutions among the seven primates reveals a significant excess of non-synonymous substitutions. Furthermore, the rate of charge-altering non-synonymous substitution is ∼1.8 times that of charge-conserving substitution, indicating that the selection is promoting the diversity of the protein charge profile. However, no difference in selective pressure on APOBEC3G is detected between hosts and non-hosts of HIV or simian immunodeficiency virus (SIV). These results, together with recent findings that the antiviral activity of APOBEC3G is not limited to HIV/SIV, suggest that the selective pressure on APOBEC3G is not solely from HIV/SIV and that APOBEC3G is a broad antiviral enzyme. The identification of pervasive positive selection for charge-altering amino acid substitutions supports the hypothesis of electrostatic interactions between APOBEC3G and vif or its functional equivalents.

Journal Article.  5320 words.  Illustrated.

Subjects: Genetics and Genomics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.