title: AIRE1A might be involved in cyclin B2 degradation in testicular lysates.
abstract: The autoimmune regulator gene Aire shows predominant expression in thymus and other immunologically relevant tissues, and is assigned the major function of programming autoreactive T-cell deletion. However, the expression of this gene in tissues outside the immune system raises a question about its possible function beyond the T-cell deletion dogma. We detected Aire in mouse testis, and the expression of AIRE protein was remarkably high in postmeiotic germ cells. Sequencing results indicate that testis expressed Aire variant 1a. AIRE could be detected in spermatozoa, with heavy localization on the principal acrosomal domains. Mouse oocytes stained negatively for AIRE before fertilization, but stained positively for AIRE 30 min after fertilization. In the zygote, the levels of AIRE correlated negatively with cyclin B2 levels. Goat testicular lysates spiked with recombinant human AIRE exhibited augmented cyclin B2 degradation in the presence of protease inhibitors, which was inhibited by MG-132, indicating the operation of proteasomal pathways. Thus, this study identifies a correlation between the presence of AIRE and proteasomal breakdown of cyclin B2, which leads us to speculate that cyclin B2 could be a target of AIRE's E3-ubiquitin ligase activity.
authors.affiliation: Division of Molecular Reproduction, Rajiv Gandhi Centre for Biotechnology, Thycaud PO, Poojappura, Trivandrum, Kerala, India.
authors.forename: M
authors.initials: M
authors.lastname: Brahmaraju
authors.forename: K P
authors.initials: KP
authors.lastname: Bhagya
authors.forename: Shiny
authors.initials: S
authors.lastname: Titus
authors.forename: Arun
authors.initials: A
authors.lastname: Sebastian
authors.forename: A N
authors.initials: AN
authors.lastname: Devi
authors.forename: Malini
authors.initials: M
authors.lastname: Laloraya
authors.forename: Pradeep G
authors.initials: PG
authors.lastname: Kumar
mesh_terms: D000371:Agglutination; D000818:Animals; D000918:Antibody Specificity; D001483:Base Sequence; D002457:Cell Extracts / Q000737:chemistry*; D056765:Cyclin B2 / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D006041:Goats; D006801:Humans; D007106:Immune Sera / Q000737:chemistry; D047468:Immunoprecipitation; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D011247:Pregnancy; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011817:Rabbits; D016415:Sequence Alignment; D013094:Spermatozoa / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism; D013737:Testis / Q000166:cytology / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D025801:Ubiquitin / Q000378:metabolism; D015044:Zona Pellucida / Q000378:metabolism; D015053:Zygote / Q000166:cytology / Q000378:metabolism; D000096927:AIRE Protein
chemical_list: D002457:Cell Extracts; D056765:Cyclin B2; D007106:Immune Sera; D020033:Protein Isoforms; D014157:Transcription Factors; D025801:Ubiquitin; D000096927:AIRE Protein; C503759:Ccnb2 protein, mouse