Effects of lysine to arginine mutations in HIV-1 Vif on its expression and viral infectivity.
We previously demonstrated that the expression in cells of human immunodeficiency virus type 1 (HIV-1) Vif is maintained at low level by proteasome-degradation. We examined the contribution of 16 lysines present in Vif (NL432 clone), which is composed of 192 amino acids (aa), to its expression within cells and to viral infectivity for non-permissive cells. To this end, various lysine-arginine mutations were introduced into wild-type (wt) Vif, and the mutational effects were monitored by transfection experiments. When all the lysines were changed to arginines, the mutant Vif was expressed in cells at much higher level than wt and was much more stable. Both N-terminal (aa nos. 34 and 36) and C-terminal (aa nos. 179 and 181) lysines were found to be almost sufficient for wt property. Different from this observation, one of the lysines at aa nos. 22 and 26 was demonstrated to be essential for the virus to grow in non-permissive cells. Our results showed that there is no clear co-relationship between the expression level of HIV-1 Vif and viral infectivity.
Khamsri
Boonruang
B
Department of Virology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503, Japan.
Fujita
Mikako
M
Kamada
Kazuya
K
Piroozmand
Ahmad
A
Yamashita
Tomoki
T
Uchiyama
Tsuneo
T
Adachi
Akio
A
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics*; D001120:Arginine / Q000235:genetics; D015153:Blotting, Western; D002460:Cell Line; D045744:Cell Line, Tumor; D015967:Gene Expression Regulation, Viral; D016346:Gene Products, vif / Q000235:genetics* / Q000378:metabolism; D015497:HIV-1 / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D009088:Mucoproteins / Q000235:genetics; D009154:Mutation / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D014162:Transfection; D054320:vif Gene Products, Human Immunodeficiency Virus
D016346:Gene Products, vif; D009088:Mucoproteins; C010393:lysin, gastropoda; D054320:vif Gene Products, Human Immunodeficiency Virus; D001120:Arginine