Transmembrane Protein 24 (TMEM24)

Full-length C21orf25 encoded a 696-aa TMEM24-related protein with similar membrane topology. Exon-intron structure was conserved between TMEM24 and C21orf25 genes. TMEM24-ABCG4 locus at human chromosome 11q23.3 and C21orf25-ABCG1 locus at human chromosome 21q22.3 were paralogous regions with insertions of other genes due to recombination during evolution. TMEM24 homologous domains (TM24H1 and TM24H2) were identified as novel domains conserved among TMEM24, C21orf25, 1300006O23, and 5830404H04. Human TMEM24, C21orf25 and their mouse homologs were type II transmembrane proteins with extracellular TM24H1 and TM24H2 domains. This is the first report on identification and characterization of the TMEM24 family.