Choroideremia Like Protein (CHML)

Using the mouse homolog of the human choroideremia cDNA as a probe, Cremers et al. (1992) identified a homologous human gene, which they designated CHML for choroideremia-like. The cDNA encompassed an open reading frame of 1,968 bp.

The product of the CHML gene, REP2, supports geranylgeranylation of most Rab proteins and may substitute for REP1 in tissues other than retina.Using semisynthetic fluorescent RAB27A, Rak et al. (2004) demonstrated that although RAB27A can be prenylated by REP2, this reaction can be effectively inhibited by other RAB proteins, providing a possible explanation for the accumulation of unprenylated RAB27A in choroideremia resulting from REP1 deficiency.