Choroideremia-like Rab escort protein 2 (CHML)

Choroideremia-like Rab escort protein 2 (CHML, also known as REP-2) is a cytosolic protein that supports the geranylgeranylation (a lipid modification) of most Rab GTPase proteins, which are essential for vesicular trafficking in eukaryotic cells[1][2][3][4]. REP-2 binds newly synthesized Rab proteins and presents them to Rab geranylgeranyltransferase for prenylation, a process required for proper Rab protein localization and function in intracellular membrane transport[2][3]. While REP-1 (encoded by the CHM gene) is critical in the retina and its deficiency causes choroideremia, REP-2 (CHML) can substitute for REP-1 in other tissues, thereby preventing systemic cellular dysfunction[1][2][3]. REP-2’s specific contribution outside the retina and in noncanonical contexts like asthma remains incompletely characterized[1]. There are no known drugs directly targeting CHML, nor is it currently considered a therapeutic target or biomarker[4].

Other names

Rab escort protein 2REP-2choroideremia-like proteinRab proteins geranylgeranyltransferase component A 2CHMLREP2choroideraemia-like proteinchoroideremia-like (Rab escort protein 2)