Floriot Sandrine, Bellutti Laura, Castille Johan, Moison Pauline, Messiaen Sébastien, Passet Bruno, Boulanger Laurent, Boukadiri Abdelhak, Tourpin Sophie, Beauvallet Christian, Vilotte Marthe, Riviere Julie, Péchoux Christine, Bertaud Maud, Vilotte Jean-Luc, Livera Gabriel
INRAe, AgroParisTech, Université Paris-Saclay, GABI, Jouy-en-Josas, France.
Laboratory of Development of the Gonads, UMRE008 Genetic Stability Stem Cells and Radiations, IRCM/IBFJ CEA, Université de Paris, Université Paris-Saclay, Paris, France.
Front Cell Dev Biol. 2022 Jan 19;9:754054. doi: 10.3389/fcell.2021.754054. eCollection 2021.
Male gametogenesis involves both mitotic divisions to amplify germ cell progenitors that gradually differentiate and meiotic divisions. Centrosomal regulation is essential for both types of divisions, with centrioles remaining tightly paired during the interphase. Here, we generated and characterized the phenotype of mutant mice devoid of , a gene encoding for a docking protein for fibers linking centrioles, and characterized their phenotype. The mice presented with no major defects, apart from male infertility due to a reduction in the spermatogonial pool and the meiotic blockade. Spermatogonial stem cells expressing Zbtb16 were not affected, whereas the differentiating spermatogonia were vastly lost. These cells displayed abnormal H2AX-staining, accompanied by an increase in the apoptotic rate. The few germ cells that survived at this stage, entered the meiotic prophase I and were arrested at a pachytene-like stage, likely due to synapsis defects and the unrepaired DNA double-strand breaks. In these cells, centrosomes split up precociously, with -tubulin foci being separated whereas these were closely associated in wild-type cells. Interestingly, this lack of cohesion was also observed in wild-type female meiocytes, likely explaining the normal fertility of female mice. Taken together, this study proposes a specific requirement of centrosome cohesion in the male germline, with a crucial role of CEP250 in both differentiating spermatogonia and meiotic spermatocytes.
雄性配子发生涉及有丝分裂以扩增逐渐分化的生殖细胞祖细胞以及减数分裂。中心体调控对于这两种分裂都至关重要,在间期中心粒保持紧密配对。在这里,我们生成并表征了缺乏一种编码连接中心粒纤维的对接蛋白的基因的突变小鼠的表型。这些小鼠除了由于精原细胞池减少和减数分裂阻滞导致雄性不育外,没有出现重大缺陷。表达Zbtb16的精原干细胞未受影响,而分化中的精原细胞大量丢失。这些细胞显示出异常的H2AX染色,伴随着凋亡率的增加。在这个阶段存活下来的少数生殖细胞进入减数分裂前期I,并停滞在类似粗线期的阶段,可能是由于联会缺陷和未修复的DNA双链断裂。在这些细胞中,中心体过早分离,γ-微管蛋白聚集体分开,而在野生型细胞中它们紧密相连。有趣的是,在野生型雌性减数分裂细胞中也观察到这种缺乏黏连的情况,这可能解释了该基因敲除雌性小鼠的正常生育能力。综上所述,这项研究提出了雄性生殖系中对中心体黏连的特定需求,CEP250在分化中的精原细胞和减数分裂的精母细胞中都起着关键作用。