Fig. 6. TLS contributes to the in vitro pairing–promoting activity present in nuclei of testicular cells. (A) Proteins extracted from nuclei of testicular cells with the TLS genotypes indicated were resolved by SDS–PAGE, blotted onto nitrocellulose and the blot was subjected to a pairing on membrane assay (POM assay). (B) TLS Western blot performed on a parallel sample. (C) Coomassie staining of a parallel-run gel to control for equal loading of nuclear proteins. Note the absence of the major POMp75 species in the extracts from TLS^–/– testes.