Fig. 2. Rat p66 mooring-sequence-selective, RNA-binding protein is a huACF homolog. Rat liver nuclear 27S editosome glycerol gradient fraction was UV cross-linked to radiolabeled apoB RNA. The proteins in the reaction were resolved by SDS PAGE, immunoblotted and exposed to X-ray film to determine the migration of the known 66 kDa and 44 kDa apoB RNA-binding proteins (left lane). Subsequently, the blot was reacted with anti-ACF (right lane). The positions of p66 and p44 UV cross-linked proteins and the cross-immunoreactive p66 are indicated. The stacking/running gel interface (S/R) is also indicated for reference.