OCT4 mediates transport of ergothioneine Authored: Jassal, B, 2010-03-19 Edited: Jassal, B, 2010-03-19 Pubmed15107849 Pubmed15795384 Reactome Database ID Release 43549241 Reactome, http://www.reactome.org ReactomeREACT_22304 Reviewed: He, L, 2010-05-10 The human gene SLC22A4 encodes the ergothioneine transporter (ETT). It was originally discovered as a organic cation/carnitine transporter (OCTN1) (Tamai I et al, 1997) but its main substrate is not carnitine. It is widely expressed and transports ergothioneine more than 100 times more efficiently than tetraethylammonium and carnitine (Grundemann D et al, 2005), leading to the name change from OCTN1 to ETT. Defects in SLC22A4 may be a cause of susceptibility to Crohn disease (CD) (Peltekova VD et al, 2004).