C155-Venus corresponds to a C-terminal portion (sequence C-terminal to residue A154) of the Venus fluorescent protein (PMID:17959720). If the C155-Venus split fluorescent fragment is brought together with a complementary split fluorescent fragment in vivo, a functional fluorescent protein may be reconstituted. C155-Venus is designed for use in the bimolecular fluorescence complementation (BiFC) technique, in which a pair of complementary split fluorescent fragments is fused to interacting peptides to study protein-protein interactions in vivo (PMID:11983170).