Expression of SPEF2 during mouse spermatogenesis and identification of IFT20 as an interacting protein

Biol Reprod. 2010 Mar;82(3):580-90. doi: 10.1095/biolreprod.108.074971. Epub 2009 Nov 4.


SPEF2 is expressed in all ciliated cells and is essential for correct sperm tail development and male fertility. We have previously identified a mutation within the SPEF2 gene as the cause for infertility because of immotile and malformed sperm tails in pigs. This mutation in pigs alters the testis-specific long SPEF2 isoform and exclusively affects the sperm tail development. In infertile boars, axonemal and all accessory structures of the sperm tail are affected; thus, SPEF2 seems to participate in the organization of these structures. In the present study, we have investigated the expression of SPEF2 during mouse spermatogenesis. SPEF2 mRNA and protein products appear to be localized both in germ cells and in Sertoli cells. In differentiating germ cells, SPEF2 protein is localized in the Golgi complex, manchette, basal body, and midpiece of the sperm tail. In mature murine sperm, SPEF2 is present in the distal part of the sperm tail midpiece. Using yeast two-hybrid assay and coimmunoprecipitation experiments, we identified an interaction between SPEF2 and the intraflagellar transport protein IFT20 in the testis. Furthermore, these two proteins colocalize in differentiating male germ cells. These results support the crucial importance of SPEF2 in sperm differentiation and involvement of SPEF2 in structuring of the sperm tail.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carrier Proteins / metabolism*
  • Gene Expression Regulation
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Models, Biological
  • Protein Binding
  • Proteins / genetics*
  • Proteins / metabolism*
  • Proteins / physiology
  • Sperm Tail / metabolism
  • Sperm Tail / physiology
  • Spermatogenesis / genetics*
  • Spermatogenesis / physiology
  • Spermatozoa / abnormalities
  • Sus scrofa
  • Swine Diseases / etiology
  • Swine Diseases / genetics
  • Swine Diseases / metabolism
  • Testis / metabolism
  • Testis / physiology
  • Tissue Distribution


  • Carrier Proteins
  • Ift20 protein, mouse
  • Proteins
  • SPEF2 protein, mouse