Necessity of the spacer peptide between CA and NC in the Rous sarcoma virus gag protein.
A mutant of Rous sarcoma virus was constructed in which the nine amino acids that separate the CA and NC sequences in the Gag protein were deleted. The spacer peptide deletion mutant produced particles containing the normal complement of viral RNA and all of the viral proteins, including reverse transcriptase. Though electron microscopy revealed particles of normal morphology, the particles were noninfectious. The normally slow maturation of the CA protein, which involves cleavage of the spacer peptide from the carboxy terminus, was bypassed in this mutant, and the association between CA and the internal components of the core appears to have been disrupted. The results suggest that the spacer peptide has an essential role in directing folding and/or oligomerization of the CA subunits within the capsid structure.
Department of Microbiology and Immunology, Hershey Medical Center, Pennsylvania State University College of Medicine 17033.
R C
RC
Craven
A E
AE
Leure-duPree
C R
CR
Erdie
C B
CB
Wilson
J W
JW
Wills
D000595:Amino Acid Sequence; D000818:Animals; D001358:Avian Sarcoma Viruses / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D002460:Cell Line; D015683:Gene Products, gag / Q000096:biosynthesis* / Q000235:genetics; D015750:Genes, gag; D016679:Genome, Viral; D008715:Methionine / Q000378:metabolism; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D016296:Mutagenesis; D011784:Quail; D017384:Sequence Deletion; D013462:Sulfur Radioisotopes; D014162:Transfection; D014771:Virion / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure
D015683:Gene Products, gag; D013462:Sulfur Radioisotopes; D008715:Methionine