RESUMO
<p><b>OBJECTIVE</b>To identify a novel isoform of hTCP11 gene and investigate its expression and alternative splicing.</p><p><b>METHODS</b>According to the sequence of human ESTs which are highly homologous to hTCP11a, primers for PCR were synthesized. Then, the amplified fragments were cloned and sequenced; some methods including BLAST, ClustalW and RT-PCR were used for genomic analysis, study of alternative splicing and gene expression among multiple tissues and different testis tissues.</p><p><b>RESULTS</b>A novel isoform of hTCP11 gene was isolated. It encodes a 440 amino acid protein that is highly homologous to the mouse 566 amino acid protein which is important to sperm function because it encodes the receptor for fertilization promoting peptide (FPP). Among TCP11a, TCP11b and TCP11c, the complicated alternative splicing was found. RT-PCR analysis of RNA extracted from human tissues revealed that the gene is only expressed in fertile adult testes, but not in azoospermic patient testes, fetal testes or other human tissues.</p><p><b>CONCLUSION</b>Our results along with the mouse Tcp-11 function suggest that the isoforms of TCP11 gene play important roles in sperm function and fertility.</p>