Krogstad Paul, Geng Yong-Zhi, Rey Osvaldo, Canon Jude, Ibarrondo F Javier, Ackerson Bradley, Patel Jignesh, Aldovini Anna
Department of Pediatrics, University of California, Los Angeles School of Medicine, Los Angeles, California 90095-1732, USA.
Virology. 2002 Mar 15;294(2):282-8. doi: 10.1006/viro.2001.1319.
The nucleocapsid protein (NC) of retroviruses is involved in viral RNA packaging and initiation of reverse transcription. NC also mediates interactions between Gag and actin filaments. We found that residues at the amino terminus of NC are involved in efficient actin binding. When alanine residues were substituted for the arginine and lysine at positions 10 and 11 of NC in HIV(NL4-3), these mutations decreased actin binding but had only a modest effect on virus infectivity. A similarly mutated virus based on the HXB2 clone of HIV was not infectious. Mutational analysis of NL4-3 NC residues demonstrated that NC polymorphisms modulated the phenotype of NC mutations. Conservative amino acid differences between HXB2 and NL4-3 NCs were sufficient to explain the difference in infectivity of viruses carrying the R10A and K11A mutations.
逆转录病毒的核衣壳蛋白（NC）参与病毒RNA包装和逆转录起始过程。NC还介导Gag与肌动蛋白丝之间的相互作用。我们发现NC氨基末端的残基参与高效的肌动蛋白结合。当用丙氨酸残基取代HIV（NL4-3）中NC第10和11位的精氨酸和赖氨酸时，这些突变降低了肌动蛋白结合，但对病毒感染性只有适度影响。基于HIV的HXB2克隆的类似突变病毒没有感染性。对NL4-3 NC残基的突变分析表明，NC多态性调节了NC突变的表型。HXB2和NL4-3 NC之间保守的氨基酸差异足以解释携带R10A和K11A突变的病毒在感染性上的差异。
