Phosphatidylcholine Transfer Protein (PCTP)

Phosphatidylcholine (PC) transfer protein (PCTP) is a cytosolic protein first purified from bovine and rat liver that catalyzes intermembrane transfer of PC. By searching an EST database for homologs of bovine Pctp, followed by 5-prime RACE and PCR of a kidney cDNA library, Cohen et al. (1999) obtained a cDNA encoding human PCTP.

The deduced 214-amino acid human protein is 76% and 80% identical to bovine and rat Pctp, respectively. Northern blot analysis revealed wide expression of an approximately 2.3-kb PCTP transcript in all tissues tested except thymus. Highest expression was detected in liver, placenta, testis, kidney, and heart, and lowest levels were found in brain and lung.