Fig. 3. Full-length Sec63p is phosphorylated at its C-terminal domain in vivo. (A) A protein extract from wild-type cells was separated by 12.5% SDS-PAGE and transferred onto nitrocellulose. The blot was treated either with (+) or without (–) CIP and subsequently incubated with extracts from yeasts either expressing Sec62_C125-Dha (+) or not (–). Bound Sec62_C125-Dha was detected with anti-Ha antibody. (B) Extracts of yeast cells expressing Sec63p or its alleles were subjected to the Sec62_C125-Dha overlay assay (top), or detection with anti-Sec63p antibody (bottom). C14 indicates a mutant of Sec63p lacking the last 14 amino acids.