Emopamil binding protein (EBP) (EBP)

Emopamil binding protein (EBP) is an integral membrane protein of the endoplasmic reticulum that functions as a 3-beta-hydroxysteroid-Delta(8),Delta(7)-isomerase (UniProt: P49728) [1]. It is a crucial enzyme in the post-squalene cholesterol biosynthetic pathway, where it catalyzes the conversion of 5-alpha-cholest-8(9)-en-3-beta-ol into lathosterol (NCBI Gene: 10682) [2]. Originally identified by its high affinity for the calcium channel blocker emopamil, EBP also serves as a component of the anti-estrogen binding site (AEBS), interacting with drugs such as tamoxifen and tesmilifene (PubMed: 10417277) [4]. Mutations in the EBP gene are the primary cause of Conradi-Hünermann-Happle syndrome (CDPX2), an X-linked dominant disorder characterized by skeletal dysplasia, cataracts, and skin defects (OMIM: 300205) [3]. Pharmacological inhibition of EBP leads to the accumulation of 8-dehydrocholesterol, which can disrupt Hedgehog signaling and induce apoptosis in cancer cells (PubMed: 10417282) [5]. Consequently, EBP is a target of interest for its roles in metabolic regulation, developmental biology, and potential oncological applications.

Other names

3-beta-hydroxysteroid-Delta(8),Delta(7)-isomeraseCholestenol Delta-isomeraseSterol Delta(8)-Delta(7) isomeraseCPXCDPX2CHO2

Inhibition of the 3-beta-hydroxysteroid-Delta(8),Delta(7)-isomerase activity, which prevents the conversion of 5-alpha-cholest-8(9)-en-3-beta-ol to lathosterol, leading to the accumulation of 8-dehydrocholesterol and depletion of cholesterol (PubMed: 10417277) [4].