FIG. 3.

Replacement of p6 with heterologous L domains. (A) M1.HG.tp2 contains the L domain of RSV Gag, while M1.HG.tp9 contains the L domain of EIAV. M1.HG.CY contains the yeast iso-1-cytochrome c sequence, which does not have an L domain. The names of the Gag cleavage products (MA, CA, NC, p6, p2, and p9) are indicated. The black box at the N termini of the constructs represent the first 10 amino acids from pp60^v-src. The squiggle represents the fatty acid myristate. (B) COS-1 cells were transfected with the indicated DNAs and labeled as described in Materials and Methods. Molecular mass standards (in kilodaltons) are indicated to the left. (C) Distribution of particle size in rate-zonal gradients. COS-1 cells were transfected with the indicated DNAs and labeled with [³⁵S]methionine for 5 h. After the labeling period, particle sizes were analyzed as described in Materials and Methods. HIV-p2 and HIV-p9 chimeras produced normal-sized particles. Arrows indicate the direction of sedimentation.