The interdomain linker region of HIV-1 capsid protein is a critical determinant of proper core assembly and stability.
The HIV-1 capsid protein consists of two independently folded domains connected by a flexible peptide linker (residues 146-150), the function of which remains to be defined. To investigate the role of this region in virus replication, we made alanine or leucine substitutions in each linker residue and two flanking residues. Three classes of mutants were identified: (i) S146A and T148A behave like wild type (WT); (ii) Y145A, I150A, and L151A are noninfectious, assemble unstable cores with aberrant morphology, and synthesize almost no viral DNA; and (iii) P147L and S149A display a poorly infectious, attenuated phenotype. Infectivity of P147L and S149A is rescued specifically by pseudotyping with vesicular stomatitis virus envelope glycoprotein. Moreover, despite having unstable cores, these mutants assemble WT-like structures and synthesize viral DNA, although less efficiently than WT. Collectively, these findings demonstrate that the linker region is essential for proper assembly and stability of cores and efficient replication.
Section on Viral Gene Regulation, Program in Genomics of Differentiation, Eunice Kennedy Shriver National Institute of Child Health, National Institutes of Health, Bethesda, MD 20892-2780, USA.
Jiyang
J
Jiang
Sherimay D
SD
Ablan
Suchitra
S
Derebail
Kamil
K
Hercík
Ferri
F
Soheilian
James A
JA
Thomas
Shixing
S
Tang
Indira
I
Hewlett
Kunio
K
Nagashima
Robert J
RJ
Gorelick
Eric O
EO
Freed
Judith G
JG
Levin
D019943:Amino Acid Substitution; D000818:Animals; D016645:Aotidae; D036022:Capsid Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D057809:HEK293 Cells; D015497:HIV-1 / Q000737:chemistry* / Q000235:genetics / Q000254:growth & development*; D006367:HeLa Cells; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism; D017434:Protein Structure, Tertiary; D014758:Viral Core Proteins / Q000378:metabolism*; D014759:Viral Envelope Proteins / Q000378:metabolism; D019065:Virus Assembly; D014779:Virus Replication; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
D036022:Capsid Proteins; C028391:G protein, vesicular stomatitis virus; D008562:Membrane Glycoproteins; D014758:Viral Core Proteins; D014759:Viral Envelope Proteins; D054301:gag Gene Products, Human Immunodeficiency Virus