Figure 2.

Analysis of VLPs from yeast expressing BMV RNA2 and CP. (A) RNA analysis. RNA from the indicated fractions (see text) was electrophoresed through 1% agarose, stained for total RNA, and imaged by laser fluorometry. BMV_P RNA (lane 5) was included as a control. The indicated bands in lanes 2 and 4 were identified as CP mRNA and RNA2 by hybridization to CP and RNA2 probes. (B) Protein analysis. Total protein was electrophoresed and visualized by silver staining. BMV_P CP (rightmost lane) was included as a control. (C) Sucrose gradient sedimentation. The resuspended pellet in lanes 4 of A and B was centrifuged through a 5–30% linear sucrose gradient, and gradient fractions were analyzed by UV absorption at 254 nm. Sedimentation profiles of yeast-derived VLPs alone (solid curve) and with BMV_P added (dotted curve) are shown. (D) RNA analysis of sucrose gradient fractions, as in A. BMV_P RNA (right lane) was used as a control. RNA2, RNA2 fragments (*), and CP mRNA were identified by hybridization to CP- and RNA2-specific probes. (E) Protein analysis of sucrose gradient fractions, as in B.