Genetic, structural, and chemical insights into the dual function of GRASP55 in germ cell Golgi remodeling and JAM-C polarized localization during spermatogenesis.
Genetic, structural, and chemical insights into the dual function of GRASP55 in germ cell Golgi remodeling and JAM-C polarized localization during spermatogenesis.
复制标题
从遗传、结构和化学角度深入了解 GRASP55 在精子发生过程中生殖细胞高尔基体重塑和 JAM-C 极化定位中的双重功能
DOI：
10.1371/journal.pgen.1006803
复制
发表时间：
2017-06
期刊：
影响因子：
4.5
通讯作者：
Aurrand-Lions M
中科院分区：
文献类型：
--
作者：
Cartier-Michaud A;Bailly AL;Betzi S;Shi X;Lissitzky JC;Zarubica A;Sergé A;Roche P;Lugari A;Hamon V;Bardin F;Derviaux C;Lembo F;Audebert S;Marchetto S;Durand B;Borg JP;Shi N;Morelli X;Aurrand-Lions M
精子发生是一个动态过程，受生殖细胞和支持细胞之间的粘附相互作用调节。生殖细胞表达由Jam3编码的连接粘附分子c (Junctional Adhesion Molecule-C, JAM-C)，定位于生殖/支持细胞的接触。JAM-C参与生殖细胞极性和顶体形成。利用蛋白质组学方法，我们证明了JAM-C在发育中的生殖细胞中与55 kDa的高尔基重组堆叠蛋白（GRASP55，由Gorasp2编码）相互作用。对Gorasp2-/-小鼠的生成和研究表明，敲除小鼠存在精子发生缺陷。在Gorasp2-/-小鼠中，精子顶体形成和JAM-C的极化定位发生改变。此外，Gorasp2-/-小鼠精母细胞高尔基体形态受到干扰。GRASP55与JAM-C或JAM-B复合物的晶体结构表明，GRASP55通过pdz介导的相互作用与jam相互作用，并诱导GRASP55的自由构象发生变化。一种硅药效团方法发现了一种叫做Graspin的化合物，它可以抑制pdz介导的GRASP55与JAMs的相互作用。用Graspin处理小鼠可抑制精细胞中JAM-C的极化定位，诱导精细胞过早释放，影响减数分裂精细胞的高尔基体形态。
Spermatogenesis is a dynamic process that is regulated by adhesive interactions between germ and Sertoli cells. Germ cells express the Junctional Adhesion Molecule-C (JAM-C, encoded by Jam3), which localizes to germ/Sertoli cell contacts. JAM-C is involved in germ cell polarity and acrosome formation. Using a proteomic approach, we demonstrated that JAM-C interacted with the Golgi reassembly stacking protein of 55 kDa (GRASP55, encoded by Gorasp2) in developing germ cells. Generation and study of Gorasp2-/- mice revealed that knock-out mice suffered from spermatogenesis defects. Acrosome formation and polarized localization of JAM-C in spermatids were altered in Gorasp2-/- mice. In addition, Golgi morphology of spermatocytes was disturbed in Gorasp2-/- mice. Crystal structures of GRASP55 in complex with JAM-C or JAM-B revealed that GRASP55 interacted via PDZ-mediated interactions with JAMs and induced a conformational change in GRASP55 with respect of its free conformation. An in silico pharmacophore approach identified a chemical compound called Graspin that inhibited PDZ-mediated interactions of GRASP55 with JAMs. Treatment of mice with Graspin hampered the polarized localization of JAM-C in spermatids, induced the premature release of spermatids and affected the Golgi morphology of meiotic spermatocytes.