1. Genetic, structural, and chemical insights into the dual function of GRASP55 in germ cell Golgi remodeling and JAM-C polarized localization during spermatogenesis
- Author
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Cartier-Michaud, Amandine, Bailly, Anne-Laure, Betzi, Stéphane, Shi, Xiaoli, Lissitzky, Jean-Claude, Zarubica, Ana, Sergé, Arnauld, ROCHE, Philippe, Lugari, Adrien, HAMON, Véronique, Bardin, Florence, Derviaux, Carine, Lembo, Frédérique, Audebert, Stéphane, Marchetto, Sylvie, Durand, Bénédicte, Borg, Jean-Paul, Shi, Ning, Morelli, Xavier, Aurrand-Lions, Michel, Institut Paoli-Calmettes, Fédération nationale des Centres de lutte contre le Cancer (FNCLCC), Centre de Recherche en Cancérologie de Marseille (CRCM), Aix Marseille Université (AMU)-Institut Paoli-Calmettes, Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Fédération nationale des Centres de lutte contre le Cancer (FNCLCC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre d'Immunologie de Marseille - Luminy (CIML), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), ANR-11-IDEX-0001,Amidex,INITIATIVE D'EXCELLENCE AIX MARSEILLE UNIVERSITE(2011), and Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)
- Subjects
Male ,Physiology ,[SDV]Life Sciences [q-bio] ,Golgi Apparatus ,Mice ,Animal Cells ,Reproductive Physiology ,Spermatocytes ,Medicine and Health Sciences ,Cell Cycle and Cell Division ,Testes ,Cells, Cultured ,Staining ,Chromosome Biology ,Intracellular Signaling Peptides and Proteins ,Specimen preparation and treatment ,Spermatids ,humanities ,Protein Transport ,Meiosis ,Seminiferous tubules ,Cell Processes ,cardiovascular system ,Cellular Types ,Anatomy ,Cellular Structures and Organelles ,Genital Anatomy ,Protein Binding ,Research Article ,endocrine system ,lcsh:QH426-470 ,education ,Immunoglobulins ,[SDV.BC]Life Sciences [q-bio]/Cellular Biology ,Germ cells ,Acrosomes ,Animals ,Spermatogenesis ,Binding Sites ,fungi ,Reproductive System ,DAPI staining ,Membrane Proteins ,Biology and Life Sciences ,Cell Biology ,Spermatogonia ,Sperm ,Mice, Inbred C57BL ,Research and analysis methods ,lcsh:Genetics ,Nuclear staining ,Carrier Proteins ,Cell Adhesion Molecules - Abstract
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., Author summary Spermatogenesis defects are a common cause of male sterility. Spermatogenesis occurs in the seminiferous tubules of the testes and involves adhesive interactions between developing germ cells and Sertoli cells. Knock-out mouse models identified several adhesion molecules that are critically involved in spermatogenesis. We previously demonstrated that the Junctional Adhesion Molecule-C (JAM-C) plays a crucial role in establishing spermatids polarity. The latter involves rearrangements of the Golgi apparatus in spermatids which contribute to acrosome formation. The present study demonstrated that the C-terminal cytosolic region of JAM-C interacted with the Golgi reassembly stacking protein of 55 kDa (GRASP55) encoded by Gorasp2 and that spermatogenesis was impaired in Gorasp2-deficient mice. We developed an inhibitor of GRASP55 interaction with JAM-C and demonstrated that treatment of wild-type mice with the inhibitory compound induced germ cell loss. Therefore, the male infertility-associated pathway identified in this study is important not only from a genetic point of view, but also as a potential target for male contraception.
- Published
- 2017