Poster Presentation Australian Society for Medical Research Annual Scientific Meeting 2016

Dynamin 2 is essential for mammalian spermatogenesis (#103)

Kate A Redgrove 1 2 3 , Ilana Berntstein 1 2 3 , Jessie Sutherland 1 2 4 , Brett Nixon 1 2 3 , Adam McCluskey 1 3 , Eileen McLaughlin 1 5
  1. University of Newcastle, CALLAGHAN, NSW, Australia
  2. 1. Priority Research Centres in Chemical Biology and Reproductive Science, University of Newcastle, Callaghan, NSW, Australia
  3. School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW, Australia
  4. School of Pharmacy and Biomedical Science, University of Newcastle, Callaghan, NSW, Australia
  5. School of Biological Sciences, University of Auckland, Auckland, New Zealand

The dynamin family of proteins have long been known to play important regulatory roles  in  membrane  remodelling  and  endocytosis,  especially  within  brain  and  neuronal  cell types.  In the  male  reproductive  tract,  dynamin  1  (DNM1)  and  dynamin  2  (DNM2)  have recently  been  shown  to  act  as  key  mediators  of  sperm  acrosome  formation  and  function. However, little is known about the roles that these proteins play in the developing germ cells during spermatogenesis. In this study, we employed the use of a DNM2 germ cell-specific knockout  model to investigate the role  of DNM2 in spermatogenesis. We  demonstrate that ablation of DNM2 in early spermatogenesis results in germ cell arrest during prophase I of meiosis,  subsequent  loss  of  all  post-meiotic  germ  cells  and  concomitant  sterility. These effects  become  exacerbated  with  age,  and  ultimately result  in  the  demise  of  the spermatogonial stem cell population and a Sertoli cell only phenotype. We also demonstrate that this activity  may be  temporally  regulated  by  phosphorylation  of  DNM2 via  the  cyclin dependent kinase 1  (CDK1)  in  early spermatogonial  cells, and  dephosphorylation  by  phosphatase PPP3CA in  meiotic and post-meiotic spermatogenesis.