Emopamil Binding Protein Like Protein (EBPL)

EBPL is distantly related to EBP (31% identity and 52% similarity) and found in animals but not in plants. EBPL is encoded by four exons on human chromosome 13q14.2 covering 30.7 kb, and a partially processed EBPL pseudogene was found on 16q21. The EBPL mRNA was expressed ubiquitously and most abundant in liver, lung and kidney. Upon heterologous expression in yeast EBPL had no detectable 3beta-hydroxysteroid sterol delta8-delta7 isomerase and sigma-ligand-binding activity. Nine out of ten amino acid residues essential for catalytic activity of EBP were conserved in EBPL. Replacement of the only differing residue reduced catalytic activity of EBP. Transfer of the divergent residue from EBP to EBPL and chimaerization of EBP and EBPL at various positions failed to restore catalytic activity of EBPL.