Amino acid sequences and alignment of yeast Elc1 (Yeast C) with rat elongin C (Rat C) and yeast Skp1 (Yeast Skp1). (A) blast alignment of rat elongin C and yeast Elc1. Identical residues are indicated by a colon. Similar residues are indicated by a period. The symbols [ ], ( ), and { } indicate the sites in rat elongin C that were previously reported to be involved in elongin B binding, elongin A/B/C complex formation, and elongin A activation, respectively (13). (B) Alignment of yeast Skp1 with yeast Elc1. Identical residues are indicated by a colon. Similar residues are indicated by a period. The yeast Elc1 construct used in our studies has an additional three residues, GSH, at the N terminus for a total of 102 residues.