FIG. 9.

Proteins in the immunoprecipitate that UV cross-link with gRNA. Uniformly labeled gRNA was added to crude mitochondrial extract and to material immunoprecipitated with MAb 46, UV cross-linked, treated with RNase A, and separated on an SDS–12% polyacrylamide gel, followed by visualization of the proteins by autoradiography as described in Materials and Methods. The cross-linked 21-kDa protein as well as proteins of ∼55, ∼16, and ∼90 kDa are evident. Sizes are indicated in kilodaltons at the left.