Ozturk Saffet
Department of Histology and Embryology, Akdeniz University, School of Medicine, Campus, Antalya, Turkey
Biol Reprod. 2015 Feb;92(2):53. doi: 10.1095/biolreprod.114.124008. Epub 2015 Jan 7.
Telomeres are located at the outermost ends of all eukaryotic chromosomes and provide for the maintenance of genomic stability and integrity during the life span of organisms. The length of telomeres shortens due to each round of DNA replication, genotoxic insults, and/or reactive oxygen species. To counteract this shortening, certain types of cells, including stem cells, male/female germline cells, granulosa cells, early embryos, and most cancerous cells, express an enzyme known as telomerase, which has the potential of restoring the shortened telomeres. Presence of telomerase activity in the male germ cells ensures maintenance of telomere length at maximum levels during spermatogenesis despite telomere attrition due to DNA replication or other genotoxic factors. In this review, telomerase activity and telomere length in mammalian male germ cells during spermatogenesis are evaluated in detail based on the studies in this field. Also, the relationship between telomerase activity/telomere length and development of male infertility is comprehensively discussed.
端粒位于所有真核生物染色体的最末端，在生物体的生命周期中维持基因组的稳定性和完整性。由于每一轮DNA复制、基因毒性损伤和/或活性氧的作用，端粒的长度会缩短。为了抵消这种缩短，某些类型的细胞，包括干细胞、雄性/雌性生殖细胞、颗粒细胞、早期胚胎和大多数癌细胞，会表达一种名为端粒酶的酶，它有恢复缩短端粒的潜力。雄性生殖细胞中端粒酶活性的存在确保了在精子发生过程中端粒长度维持在最大水平，尽管由于DNA复制或其他基因毒性因素会导致端粒磨损。在这篇综述中，基于该领域的研究，详细评估了哺乳动物雄性生殖细胞在精子发生过程中的端粒酶活性和端粒长度。此外，还全面讨论了端粒酶活性/端粒长度与男性不育症发生之间的关系。
