Cell. 1990 Oct 5;63(1):77-86. Unique Identifier : AIDSLINE MED/91004229
Two different morphogenic processes of retroviral capsid assembly have
been observed: the capsid is either assembled at the plasma membrane
during the budding process (type C), or preassembled within the
cytoplasm (types B and D). We describe here a gag mutant of Mason-Pfizer
monkey virus, a type D retrovirus, in which a tryptophan substituted for
an arginine in the matrix protein results in efficient assembly of
capsids at the plasma membrane through a morphogenic process similar to
that of type C retroviruses. We conclude that a type D retrovirus Gag
polyprotein contains an additional, dominant signal that prevents
immediate transport of precursors from the site of biosynthesis to the
plasma membrane. Instead, they are directed to and retained at a
cytoplasmic site where a concentration sufficient for self-assembly into
capsids occurs. Thus, capsid assembly processes for different
retroviruses appear to differ only in the intracellular site to which
capsid precursors are directed.
Amino Acid Sequence Animal Capsid/GENETICS Cell Line Clone Cells
Comparative Study Gene Products, gag/GENETICS Hela Cells/METABOLISM
Molecular Sequence Data Morphogenesis *Mutation Retroviridae/GROWTH &
DEVELOPMENT/*GENETICS Retroviruses, Type D/GROWTH &
DEVELOPMENT/*GENETICS Sequence Homology, Nucleic Acid Support, U.S.
Gov't, P.H.S. Transfection Viral Matrix Proteins/*GENETICS
Virion/GROWTH & DEVELOPMENT/GENETICS JOURNAL ARTICLE