title: Characterization of MAGEG2 with testis-specific expression in mice.
abstract: Male germ cell development is a well-defined process occurring in numerous seminiferous tubules of the testis. Uncovering testicular novel genes related to intrinsic regulation of spermatogenesis is essential for the understanding of spermatogenesis. In the present study, we investigated mouse Mageg2, which belongs to a group of melanoma-associated antigens (MAGEs). Mageg2 is transcribed in the testis specifically, and its expression level is increased at the pachytene spermatocyte stage, indicating that Mageg2 is expressed predominantly in germ cells. We generated an antibody against mouse MAGEG2 for further characterization at the protein level. Immunoblot analysis suggested that MAGEG2 has specific testicular expression and the expression primarily occurred in pachytene spermatocytes. Proteomic analyses demonstrated that mouse MAGEG2 binded to testicular germ cell-specific serine/threonine-protein kinase 31 (STK31) and heat shock protein 9 (HSPA9). Direct binding with both interaction partners was confirmed by co-immunoprecipitation. We found that STK31 and HSPA9 bind MAGEG2 directly but not with each other. Interestingly, MAGEG2 reduced the kinase activity of STK31. Our study suggests that mouse MAGEG2 has at least two functions, including chaperone activity related to HSPA9 and regulation of pachytene spermatocyte-specific kinase, STK31. Altogether, our results provide the first information about MAGEG2 at the transcript and protein levels and suggest its potential molecular functions.
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea.
authors.forename: Juri
authors.initials: J
authors.lastname: Jeong
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea.
authors.forename: Sora
authors.initials: S
authors.lastname: Jin
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea.
authors.forename: Heejin
authors.initials: H
authors.lastname: Choi
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea.
authors.forename: Jun Tae
authors.initials: JT
authors.lastname: Kwon
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea.
authors.forename: Jihye
authors.initials: J
authors.lastname: Kim
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea.
authors.forename: Jaehwan
authors.initials: J
authors.lastname: Kim
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea.
authors.forename: Zee Yong
authors.initials: ZY
authors.lastname: Park
authors.affiliation: School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea.
authors.forename: Chunghee
authors.initials: C
authors.lastname: Cho
mesh_terms: D000818:Animals; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D010766:Phosphorylation; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D013090:Spermatocytes / Q000378:metabolism; D013091:Spermatogenesis / Q000502:physiology*; D013737:Testis / Q000378:metabolism*
chemical_list: D006360:Heat-Shock Proteins; D011506:Proteins; D017346:Protein Serine-Threonine Kinases; C572900:STK31 protein, mouse