Identification of a novel testis-specific gene in mice and its potential roles in spermatogenesis

Aim Identification of a novel gene in mouse testis and its relation to spermatogenesis. Methods Genes expressed during different developmental stages of the mouse testis were screened by DNA microarray. The results of chip analysis were authenticated by reverse transcription-polymerase chain reaction (RT-PCR) technique, as well as the tissue distribution of the selected genes. The characteristics of the selected genes were analyzed by bioinformatics tools. Results A novel gene, TSC77, was identified and located at the mouse chromosome 2G1. The full cDNA length of TSC77 was 2280 bp, with a 2046 bp open reading frame encoding a 681 amino acids protein with a predicted molecular weight of 77.17 kDa. The results of subcellular localization of GFP-TSC77 fusion protein indicated TSC77 protein was located in the nucleus of Cos-7 cells. The analysis of multiple amino acid sequence alignment showed that TSC77 protein was highly homologous with the human CAI40813 (C2orf26 gene, 76%), and rat XP_ 230651 (77%). Three putative domains including nicotine amide dinucleotide phosphate (NAD(P))-nitrite reductase (NirB) domain, uncharacterized NAD flavin adenine dinucleotide (FAD)-dependent dehydrogenases (HcaD) domain, and nicotinamide adenine dinucleotide (NADH) dehydrogenase (Ndh) domain were predicted at the protein site 168-309, 187-245, 181-216, respectively. Gene expression anlysis showed that the mouse TSC77 is preferentially expressed in the mouse testis and its expression increased gradually from the day 9 to day 21. Conclusion Based on its expression during mouse development, TSC77 may play an important role during mouse spermatogenesis.