Cloning of Tibetan sheep (Ovis aries) PRDX5 gene and its expression in testis

Peroxiredoxin 5 (PRDX5) is a type of thioredoxin that participates in a variety of biological processes in organisms. To understand the role of PRDX5 gene in testicular development and spermatogenesis, Tibetan sheep (Ovis aries) at different developmental stages (3 months, 1 year, and 3 years) were studied in this experiment. The CDS region of the PRDX5 gene was cloned using RT-PCR and other techniques and analyzed using bioinformatics tools. Simultaneously, the expression and distribution pattern of the PRDX5 gene in Tibetan sheep testis at different developmental stages were detected by quantitative real-time PCR (qRT-PCR), western blot, and immunohistochemistry at the transcription and translation levels. The results showed that the CDS region of the Tibetan sheep PRDX5 gene was 659 bp in length and encodes 219 amino acids. Protein structure prediction showed that PRDX5 was dominated by an α-helix. The phylogenetic tree showed that the PRDX5 gene of Tibetan sheep was closely related to that of goats (Capra hircus). The results of qRT-PCR and western blot showed that the relative expression of PRDX5 gene mRNA in the testes of Tibetan sheep at 1 year (sexual maturity) and 3 years of age (adult) was extremely significant (P < 0.01) and higher than that at 3 months of age (before sexual maturity), while the expression of PRDX5 protein is extremely significant (P < 0.01) at less than 3 months of age, and both tend to be stable after sexual maturity. Immunohistochemistry results showed that the PRDX5 protein was expressed in the Sertoli cells and stromal cells of Tibetan sheep testis at different developmental stages. It is speculated that the PRDX5 gene may affect the spermatogenesis microenvironment by regulating the level of intracellular ROS, thereby affecting the process of spermatogenesis.