Figure 5.

Interaction of CVB3 5′-UTR RNA with La protein from mouse pancreas. (A) ³²P-labeled CVB3 5′-UTR RNA was UV crosslinked to pancreas cytoplasmic extract of Balb/c mice (lane 2). Lane 1 contains the free probe in the absence of any added proteins. (B) ³²P-labeled CVB3 5′-UTR RNA–protein complexes from the pancreas extract were immunoprecipitated using anti-La antibodies (lane 2) and pre-immune serum (lane 1). (C and D) UV crosslinking and immunoprecipitation of ³²P-labeled CVB3 5′-UTR RNA–protein complexes from liver cytoplasmic extract of Balb/c mice. Lanes 1 and 2 correspond to those in (A) and (B). Lane 3 in (D) contains purified His-tagged La protein immunoprecipitated with anti-La antibodies. The samples were resolved by SDS–10% PAGE, the gels were dried and exposed for phosphorimaging. Lane M represents ¹⁴C-labeled protein markers. The arrow indicates CVB3 5′-UTR RNA–La complex.