Molecular cloning and characterization of phosphatidylcholine transfer protein-like protein gene expressed in murine haploid germ cells

We have isolated a cDNA clone specifically expressed in spermiogenesis from a subtracted cDNA library of mouse testis. The cDNA consisted of 1392 nucl eotides and had an open reading frame of 873 nucleotides encoding a protein of 291 amino acid residues. Computer-mediated homology search revealed tha t the nucleotide sequence was unique but the deduced amino acid sequence ha d similarity to mouse phosphatidylcholine transfer protein (PCTP). We named this newly isolated gene PCTP-like protein. Northern blot analysis reveale d a 1.4-kilobase mRNA expressed in the testis, kidney, river, and intestine with the highest level in the testis. Messenger RNA expression in the test is was detected first on Day 23 in postnatal development and then increased up to adulthood. The protein, having a molecular weight of approximately 4 0 000, was encoded by the mRNA and was detected at the tail of the elongate d spermatids and sperm by immunohistochemical staining.