(D) Endogenous NAF‐1 cross‐links with BCL‐2 at the ER. LM purified from H1299 neo and HA‐BCL‐2b5 cells were subjected to cross‐linking by BMH and immunoprecipitation with anti‐NAF‐1 antibody. Precipitates were analysed by immunoblot with anti‐BCL‐2. 