title: SLXL1, a novel acrosomal protein, interacts with DKKL1 and is involved in fertilization in mice.
abstract: BACKGROUND
  Spermatogenesis is a complex cellular developmental process which involves diverse families of genes. The Xlr (X-linked, lymphocyte regulated) family includes multiple members, only a few of which have reported functions in meiosis, post-meiotic maturation, and fertilization of germ cells. Slx-like1 (Slxl1) is a member of the Xlr family, whose expression and function in spermatogenesis need to be elucidated.
  
  
  RESULTS
  The mRNA and protein expression and localization of Slxl1 were investigated by RT-PCR, Western blotting and immunohistochemistry in different tissues and at different stages of spermatogenesis. The interacting partner of SLXL1 was examined by co-immunoprecipitation and co-localization. Assessment of the role of SLXL1 in capacitation, acrosome reaction, zona pellucida binding/penetration, and fertilization was carried out in vitro using blocking antisera. The results showed that Slxl1 mRNA and protein were specifically expressed in the testis. SLXL1 was exclusively located in the acrosome of post-meiotic germ cells and interacts with DKKL1 (Dickkopf-like1), which is an acrosome-associated protein and plays an important role in fertilization. The rates of zona pellucida binding/penetration and fertilization were significantly reduced by the anti-SLXL1 polyclonal antiserum.
  
  
  CONCLUSIONS
  SLXL1 is the first identified member of the XLR family that is associated with acrosome and is involved in zona pellucid binding/penetration and subsequent fertilization. These results, together with previous studies, suggest that Xlr family members participate in diverse processes from meiosis to fertilization during spermatogenesis.
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Animal Reproduction Institute, Guangxi University, Nanning, Guangxi, People's Republic of China.
authors.forename: Xin-jie
authors.initials: XJ
authors.lastname: Zhuang
authors.forename: Xiao-jun
authors.initials: XJ
authors.lastname: Hou
authors.forename: Shang-Ying
authors.initials: SY
authors.lastname: Liao
authors.forename: Xiu-Xia
authors.initials: XX
authors.lastname: Wang
authors.forename: Howard J
authors.initials: HJ
authors.lastname: Cooke
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Han
mesh_terms: D000177:Acrosome / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D005306:Fertilization; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
chemical_list: D009687:Nuclear Proteins; D011506:Proteins; D016601:RNA-Binding Proteins; C562172:Slx-like1 protein, mouse; C414705:soggy protein, mouse