HEG Homolog 1 (HEG1)

HEG1Contains 2 EGF-like domains.EGF-like domain is an evolutionary conserved protein domain, of about thirty to forty amino-acid residues long, which was found in a large number of mostly animal proteins.

All these repeats are found in the extracellular domain of membrane-bound proteins or in proteins known to be secreted (except in prostaglandin H/G synthase). The EGF domain includes six cysteine residues which have been shown (in EGF) to be involved in three disulfide bonds. The main structure is a two-stranded beta-sheet followed by a loop to a C-terminal short two-stranded sheet. In the case of coagulation factors IX and X and anticoagulants proteins C and S, calcium has been found to bind to the EGF-like domains.