Npat-dependent programmed Sertoli cell proliferation is indispensable for testis cord development and germ cell mitotic arrest

FASEB J. 2019 Aug;33(8):9075-9086. doi: 10.1096/fj.201802289RR. Epub 2019 May 14.

Abstract

As the major somatic cell type, Sertoli cells undergo active proliferation and play essential roles to establish testis cord at fetal stage. They also function to maintain germ cell development throughout the life of testicular development. However, the significance of Sertoli cell number for testis cord development and gonocyte fate is still unclear. Nuclear protein ataxia-telangiectasia (NPAT, also known as p220), a substrate of cyclin E/cyclin-dependent kinase 2, is well known as a regulator of cell proliferation through regulating histone expression. To study the role of NPAT during Sertoli cell development, we generated a mouse strain carrying conditional floxed Npat alleles, when crossing with anti-Müllerian hormone-cre, leading to the specific deletion of Npat in Sertoli cells. Npat disruption in Sertoli cells inhibited the programmed proliferation of fetal Sertoli cells resulting in disruption of developing testis cords, and subsequent postnatal mutant testes were severely hypoplastic. Germ cells, which are presumed to be in quiescent status during perinatal stage, exited G0 phase arrest and re-enter mitotic cell cycle prematurely. Of particular note, some germ cells possessed the meiotic signal in Npat-deficient testes. Our data thus indicates that the function of Npat-dependent Sertoli cells is essential at multiple steps in testis development, and this study also identifies Sertoli cells as a major regulator of germ cell development, which are required to maintain a local growth niche to repress premature mitosis and meiosis of gonocytes.-Jiang, X., Yin, S., Fan, S., Bao, J., Jiao, Y., Ali, A., Iqbal, F., Xu, J., Zhang, Y., Shi, Q. Npat-dependent programmed Sertoli cell proliferation is indispensable for testis cord development and germ cell mitotic arrest.

Keywords: Sertoli cell; gonocyte; spermatogenesis; testis cord.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / genetics
  • Apoptosis / physiology
  • Cell Cycle Checkpoints / genetics
  • Cell Cycle Checkpoints / physiology
  • Cell Cycle Proteins / deficiency
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Cell Proliferation / genetics
  • Cell Proliferation / physiology
  • Female
  • Male
  • Meiosis / genetics
  • Meiosis / physiology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mitosis / genetics
  • Mitosis / physiology
  • Nuclear Proteins / deficiency
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Pregnancy
  • Seminiferous Tubules / abnormalities
  • Seminiferous Tubules / embryology
  • Seminiferous Tubules / metabolism
  • Sertoli Cells / cytology*
  • Sertoli Cells / metabolism*
  • Spermatogenesis / genetics
  • Spermatogenesis / physiology
  • Spermatozoa / cytology
  • Spermatozoa / metabolism
  • Testis / cytology
  • Testis / embryology*
  • Testis / metabolism*

Substances

  • Cell Cycle Proteins
  • Nuclear Proteins
  • p220(NPAT) protein, mouse