Transmembrane Phosphatase With Tensin Homology (TPTE)

TPIP is a member of a large class of membrane-associated phosphatases with substrate specificity for the 3-position phosphate of inositol phospholipids. The cDNA shares sequence homology with chicken tensin, bovine auxilin, and rat cyclin G-associated kinase. The entire polypeptide sequence also shares significant homology with the tumor suppressor protein PTEN. Its expression pattern, sequence homologies, and the presence of a potential tyrosine phosphatase domain suggested that TPTE may be involved in the signal transduction pathways of the endocrine or spermatogenic function of the testis. Various methods indicated that the TPTE gene has highly homologous copies on chromosomes 13, 15, 22, and Y. The authors estimated that the minimum number of copies of TPTE in the haploid human genome is 7 in males and 6 in females.