Yang Fang, Silber Sherman, Leu N Adrian, Oates Robert D, Marszalek Janet D, Skaletsky Helen, Brown Laura G, Rozen Steve, Page David C, Wang P Jeremy
Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Infertility Center of St. Louis, St. Luke's Hospital, St. Louis, MO, USA.
EMBO Mol Med. 2015 Sep;7(9):1198-210. doi: 10.15252/emmm.201404967.
Genome-wide recombination is essential for genome stability, evolution, and speciation. Mouse Tex11, an X-linked meiosis-specific gene, promotes meiotic recombination and chromosomal synapsis. Here, we report that TEX11 is mutated in infertile men with non-obstructive azoospermia and that an analogous mutation in the mouse impairs meiosis. Genetic screening of a large cohort of idiopathic infertile men reveals that TEX11 mutations, including frameshift and splicing acceptor site mutations, cause infertility in 1% of azoospermic men. Functional evaluation of three analogous human TEX11 missense mutations in transgenic mouse models identified one mutation (V748A) as a potential infertility allele and found two mutations non-causative. In the mouse model, an intronless autosomal Tex11 transgene functionally substitutes for the X-linked Tex11 gene, providing genetic evidence for the X-to-autosomal retrotransposition evolution phenomenon. Furthermore, we find that TEX11 protein levels modulate genome-wide recombination rates in both sexes. These studies indicate that TEX11 alleles affecting expression level or substituting single amino acids may contribute to variations in recombination rates between sexes and among individuals in humans.
全基因组重组对于基因组稳定性、进化和物种形成至关重要。小鼠Tex11是一个X连锁的减数分裂特异性基因,可促进减数分裂重组和染色体联会。在此,我们报告TEX11在非梗阻性无精子症的不育男性中发生突变,并且小鼠中的类似突变会损害减数分裂。对一大群特发性不育男性进行的基因筛查显示,TEX11突变,包括移码突变和剪接受体位点突变,在1%的无精子症男性中导致不育。在转基因小鼠模型中对三种类似的人类TEX11错义突变进行功能评估,确定一种突变(V748A)为潜在的不育等位基因,并发现两种突变无致病性。在小鼠模型中,一个无内含子的常染色体Tex11转基因在功能上替代了X连锁的Tex11基因,为X到常染色体逆转座进化现象提供了遗传学证据。此外,我们发现TEX11蛋白水平调节两性的全基因组重组率。这些研究表明,影响表达水平或替代单个氨基酸的TEX11等位基因可能导致人类两性之间以及个体之间重组率的差异。