Bellil Hela, Ghieh Farah, Hermel Emeline, Mandon-Pepin Béatrice, Vialard François
Département de Génétique, CHI de Poissy St Germain en Laye, Poissy, France.
Université Paris-Saclay, UVSQ, INRAE, BREED, F-78350, Jouy-en-Josas, France.
Basic Clin Androl. 2021 Apr 22;31(1):9. doi: 10.1186/s12610-021-00127-7.
Spermatogenesis is a complex process regulated by a multitude of genes. The identification and characterization of male-germ-cell-specific genes is crucial to understanding the mechanisms through which the cells develop. The term "TEX gene" was coined by Wang et al. (Nat Genet. 2001; 27: 422-6) after they used cDNA suppression subtractive hybridization (SSH) to identify new transcripts that were present only in purified mouse spermatogonia. TEX (Testis expressed) orthologues have been found in other vertebrates (mammals, birds, and reptiles), invertebrates, and yeasts. To date, 69 TEX genes have been described in different species and different tissues. To evaluate the expression of each TEX/tex gene, we compiled data from 7 different RNA-Seq mRNA databases in humans, and 4 in the mouse according to the expression atlas database.Various studies have highlighted a role for many of these genes in spermatogenesis. Here, we review current knowledge on the TEX genes and their roles in spermatogenesis and fertilization in humans and, comparatively, in other species (notably the mouse). As expected, TEX genes appear to have a major role in reproduction in general and in spermatogenesis in humans but also in all mammals such as the mouse. Most of them are expressed specifically or predominantly in the testis. As most of the TEX genes are highly conserved in mammals, defects in the male (gene mutations in humans and gene-null mice) lead to infertility. In the future, cumulative data on the human TEX genes' physiological functions and pathophysiological dysfunctions should become available and is likely to confirm the essential role of this family in the reproductive process. Thirteen TEX genes are now referenced in the OMIM database, and 3 have been linked to a specific phenotype. TEX11 (on Xq13.1) is currently the gene most frequently reported as being associated with azoospermia.
精子发生是一个由众多基因调控的复杂过程。雄性生殖细胞特异性基因的鉴定和表征对于理解这些细胞的发育机制至关重要。“TEX基因”这一术语是由Wang等人（《自然遗传学》，2001年；27卷：422 - 426页）在使用cDNA抑制消减杂交（SSH）鉴定仅存在于纯化的小鼠精原细胞中的新转录本后创造的。在其他脊椎动物（哺乳动物、鸟类和爬行动物）、无脊椎动物和酵母中都发现了TEX（睾丸表达）直系同源基因。迄今为止，已在不同物种和不同组织中描述了69个TEX基因。为了评估每个TEX/tex基因的表达，我们根据表达图谱数据库，汇编了来自人类7个不同RNA测序mRNA数据库和小鼠4个数据库的数据。各种研究都强调了其中许多基因在精子发生中的作用。在这里，我们综述了关于TEX基因及其在人类精子发生和受精中的作用的现有知识，并与其他物种（特别是小鼠）进行比较。不出所料，TEX基因似乎在一般生殖中以及在人类精子发生中，而且在所有哺乳动物如小鼠中都起着主要作用。它们中的大多数在睾丸中特异性表达或主要在睾丸中表达。由于大多数TEX基因在哺乳动物中高度保守，雄性的缺陷（人类基因突变和基因敲除小鼠）会导致不育。未来，关于人类TEX基因生理功能和病理生理功能障碍的累积数据应该会出现，并可能证实这个家族在生殖过程中的重要作用。目前，OMIM数据库中引用了13个TEX基因，其中3个与特定表型相关。TEX11（位于Xq13.1）目前是最常被报道与无精子症相关的基因。
