Molecular cloning of human testis mRNA specifically expressed in haploid germ cells, having structural homology with the A-kinase anchoring proteins.

We have cloned a human testis specific gene (hi), which encodes for a protein having regional homologies to the domain of A-kinase anchoring proteins. Open reading frame encodes a protein of 860 amino acids. The predicted protein has a molecular weight 95.8 kD and contains 32 cysteine residues and 34 potential phosphorylation sites. The deduced protein analysis revealed an eukaryotic secretory signal with a potential cleavage site. Northern blot analysis detected a single transcript of approximately 3.0 kb in testis and not in any other somatic tissues. Expression of hi transcript was observed only in round spermatids indicating post meiotic haploid gene expression.