For 10 points, name this lentivirus that reduces the number of CD4-plus helper T cells and causes AIDS.
This virus uses the small protein VPU to promote the proteolysis of antigens as they are made. Resistance to this virus is conferred by a 32-base-pair deletion that prevents the expression of the chemokine receptor CCR5. The fusogen Gp41 is exposed when Gp120 on the surface of this virus's capsid binds to a cell. One drug used to treat infection with this virus is AZT, which combats the reverse transcriptase this virus uses to infect host cells. For 10 points, name this lentivirus that reduces the number of CD4-plus helper T cells and causes AIDS.
This virus uses the small protein VPU to promote the proteolysis of antigens as they are made.
HIV [or human immunodeficiency virus; do not accept "AIDS"]