title: Identification and Characterization of Xlr5c as a Novel Nuclear Localization Protein in Mouse Germ Cells.
abstract: BACKGROUND
  Spermatogenesis is the complex process by which diploid stem cells generate haploid germ cells in gamete production. Members of the Xlr (X-chromosome linked, lymphocyte regulated) superfamily play essential roles in spermatogenesis. The expression, localization and role in spermatogenesis of one such member, Xlr5c, has not been reported previously.
  
  
  RESULTS
  Xlr5c mRNA and protein levels in murine testes and other tissues were investigated using RT-PCR and Western blotting. Xlr5c was abundantly transcribed in mouse testes, particularly during the early stages of spermatogenesis and throughout prophase I in the nuclei of spermatocytes. Xlr5c was specifically localized at synaptonemal complexes(SCs) region in preleptotene and pachytene spermatocytes, as was the homologous Xlr protein Sycp3.
  
  
  CONCLUSIONS
  These results suggest that Xlr5c was abundantly transcribed in germ cells, localized at SCs region, where it may play a potential role during the early stages of spermatogenesis. Identification and characterization of this novel testis protein may offer a new perspective for understanding of the molecular mechanisms involved in germ cell differentiation.
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Key Laboratory of Assisted Reproduction, Ministry of Education, Peking University Third Hospital, Beijing 100191, PR China.
authors.forename: Xin-Jie
authors.initials: XJ
authors.lastname: Zhuang
authors.affiliation: Department of Urology, the Third Hospital of Peking University, Beijing 100191, PR China.
authors.forename: Wen-hao
authors.initials: WH
authors.lastname: Tang
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Key Laboratory of Assisted Reproduction, Ministry of Education, Peking University Third Hospital, Beijing 100191, PR China.
authors.forename: Chang-yu
authors.initials: CY
authors.lastname: Liu
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Key Laboratory of Assisted Reproduction, Ministry of Education, Peking University Third Hospital, Beijing 100191, PR China.
authors.forename: Jin-liang
authors.initials: JL
authors.lastname: Zhu
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Key Laboratory of Assisted Reproduction, Ministry of Education, Peking University Third Hospital, Beijing 100191, PR China.
authors.forename: Xue
authors.initials: X
authors.lastname: Feng
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Key Laboratory of Assisted Reproduction, Ministry of Education, Peking University Third Hospital, Beijing 100191, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yan
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Key Laboratory of Assisted Reproduction, Ministry of Education, Peking University Third Hospital, Beijing 100191, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Lian
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Key Laboratory of Assisted Reproduction, Ministry of Education, Peking University Third Hospital, Beijing 100191, PR China.
authors.forename: Ping
authors.initials: P
authors.lastname: Liu
authors.affiliation: Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Key Laboratory of Assisted Reproduction, Ministry of Education, Peking University Third Hospital, Beijing 100191, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Qiao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D015153:Blotting, Western; D018797:Cell Cycle Proteins; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins; D007124:Immunoenzyme Techniques; D008297:Male; D049469:Meiotic Prophase I / Q000502:physiology; D051379:Mice; D008969:Molecular Sequence Data; D019913:Nuclear Localization Signals; D009687:Nuclear Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D011817:Rabbits; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013091:Spermatogenesis / Q000502:physiology*; D013737:Testis / Q000166:cytology / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D019913:Nuclear Localization Signals; D009687:Nuclear Proteins; D012333:RNA, Messenger; C490062:Sycp3 protein, mouse; C000607002:Xlr5c protein, mouse