FIG. 4.

Extracts from HIV-1 viral particles exclusively contain the mitochondrial LysRS species. (A) A total extract of purified HIV-1 particles (HIV) was analyzed by Western blotting using antibodies directed to full-length LysRS (IgG × KRS) or to synthetic peptides specific for the mitochondrial (IgG × mKRS) or cytoplasmic (IgG × cKRS) form of human LysRS. The HIV extract was analyzed along with MARS, with the total and mitochondrial fractions of a U937 cell extract, and with a total extract of HeLa cells that overexpressed mito-LysRS. x, the polypeptide cross-reacting with IgG × mKRS. (B) An HIV-1 extract was also probed with antibodies directed to cytochrome c (IgG × CytC).