Fig. (2) Ubiquitylation of Sec23a in Hek293T cells. (A) SDS-PAGE and Coomassie-staining of Huh7 (H) and Hek293T (K) cells transiently transfected with 3X-FLAG-Sec23a at 48 h of expression. Total extracts (Lysates), the FLAG-immunoprecipitated proteins and the unbound proteins are showed as steps of the 3xFLAG-Sec23a purification. (B) Hek293T cells were co-transfected with the pHA-Ubiquitin expression vector and the 3xFLAG-Sec23a vector. Cell lysates were immunoprecipitated and checked by Western Blot with the indicated antibodies as in (Fig. 1).