title: RAB10 Interacts with the Male Germ Cell-Specific GTPase-Activating Protein during Mammalian Spermiogenesis.
abstract: According to recent estimates, 2%-15% of couples are sterile, and approximately half of the infertility cases are attributed to male reproductive factors. However, the reasons remain undefined in approximately 25% of male infertility cases, and most infertility cases exhibit spermatogenic defects. Numerous genes involved in spermatogenesis still remain unknown. We previously identifiedMale Germ Cells Rab GTPase-Activating Proteins(MGCRABGAPs) through cDNA microarray analysis of human testicular tissues with spermatogenic defects. MGCRABGAP contains a conserved RABGAP catalytic domain, TBC (Tre2/Bub2/Cdc16). RABGAP family proteins regulate cellular function (e.g., cytoskeletal remodeling, vesicular trafficking, and cell migration) by inactivating RAB proteins. MGCRABGAP is a male germ cell-specific protein expressed in elongating and elongated spermatids during mammalian spermiogenesis. The purpose of this study was to identify proteins that interact with MGCRABGAP during mammalian spermiogenesis using a proteomic approach. We found that MGCRABGAP exhibited GTPase-activating bioability, and several MGCRABGAP interactors, possible substrates (e.g., RAB10, RAB5C, and RAP1), were identified using co-immunoprecipitation (co-IP) and nano liquid chromatography-mass spectrometry/mass spectrometry (nano LC-MS/MS). We confirmed the binding ability between RAB10 and MGCRABGAP via co-IP. Additionally, MGCRABGAP-RAB10 complexes were specifically colocalized in the manchette structure, a critical structure for the formation of spermatid heads, and were slightly expressed at the midpiece of mature spermatozoa. Based on these results, we propose that MGCRABGAP is involved in mammalian spermiogenesis by modulating RAB10.
authors.affiliation: Graduate Institute of Biomedical and Pharmaceutical Science, Fu-Jen Catholic University, New Taipei City 24205, Taiwan. 084952@mail.fju.edu.tw.
authors.forename: Ying-Hung
authors.initials: YH
authors.lastname: Lin
authors.affiliation: Department of Urology, En Chu Kong Hospital, New Taipei City 23702, Taiwan. koacurtis@gmail.com.
authors.forename: Chih-Chun
authors.initials: CC
authors.lastname: Ke
authors.affiliation: Department of Chemistry, Fu Jen Catholic University, New Taipei City 24205, Taiwan. vic0009@gmail.com.
authors.forename: Ya-Yun
authors.initials: YY
authors.lastname: Wang
authors.affiliation: Bone and Joint Research Center, Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan. mfchen0@gmail.com.
authors.forename: Mei-Feng
authors.initials: MF
authors.lastname: Chen
authors.affiliation: Department and Graduate Institute of Aquaculture, National Kaohsiung Marine University, Kaohsiung 81157, Taiwan. tmtonychen@webmail.nkmu.edu.tw.
authors.forename: Tsung-Ming
authors.initials: TM
authors.lastname: Chen
authors.affiliation: School of Medicine, Fu Jen Catholic University, New Taipei City 24205, Taiwan. 089052@mail.fju.edu.tw.
authors.forename: Wei-Chi
authors.initials: WC
authors.lastname: Ku
authors.affiliation: Graduate Institute of Biomedical and Pharmaceutical Science, Fu-Jen Catholic University, New Taipei City 24205, Taiwan. 053824@mail.fju.edu.tw.
authors.forename: Han-Sun
authors.initials: HS
authors.lastname: Chiang
authors.affiliation: Division of Urology, Department of Surgery, Shin-Kong Wu-Su Memorial Hospital, Taipei 11101, Taiwan. M000732@ms.skh.org.tw.
authors.forename: Chung-Hsin
authors.initials: CH
authors.lastname: Yeh
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid; D020690:GTPase-Activating Proteins / Q000378:metabolism*; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D008297:Male; D008322:Mammals / Q000378:metabolism*; D051379:Mice; D011485:Protein Binding; D020543:Proteome / Q000378:metabolism; D040901:Proteomics / Q000379:methods; D013077:Sperm Head / Q000378:metabolism; D032961:Sperm Midpiece / Q000378:metabolism; D013087:Spermatids / Q000378:metabolism; D013091:Spermatogenesis; D013094:Spermatozoa / Q000378:metabolism; D053719:Tandem Mass Spectrometry; D020691:rab GTP-Binding Proteins / Q000378:metabolism*
chemical_list: D020690:GTPase-Activating Proteins; D020543:Proteome; C115995:mgcRacGAP; C538901:Rab10 protein, human; D020691:rab GTP-Binding Proteins
keywords: Male Germ Cells Rab GTPase-Activating Proteins; RAB10; spermatogenesis