title: The Y-encoded gene zfy2 acts to remove cells with unpaired chromosomes at the first meiotic metaphase in male mice.
abstract: During male but not female mammalian meiosis, there is efficient apoptotic elimination of cells with unpaired (univalent) chromosomes at the first meiotic metaphase (MI) [1]. Apoptotic elimination of MI spermatocytes is seen in response to the univalent X chromosome of XSxr(a)O male mice [2], in which the X chromosome carries Sxr(a) [3, 4], the Y-chromosome-derived sex-reversal factor that includes the testis determinant Sry. Sxr(b) is an Sxr(a)-derived variant in which a deletion has removed six Y short-arm genes and created a Zfy2/Zfy1 fusion gene spanning the deletion breakpoint [4, 5]. XSxr(b)O males have spermatogonial arrest that can be overcome by the re-addition of Eif2s3y from the deletion as a transgene; however, XSxr(b)OEif2s3y transgenic males do not show the expected elimination of MI spermatocytes in response to the univalent [6]. Here we show that these XSxr(b)OEif2s3y males have an impaired apoptotic response with completion of the first meiotic division, but there is no second meiotic division. We then show that Zfy2 (but not the closely related Zfy1) is sufficient to reinstate the apoptotic response to the X univalent. These findings provide further insight into the basis for the much lower transmission of chromosomal errors originating at the first meiotic division in men than in women [7].
authors.affiliation: Division of Stem Cell Biology and Developmental Genetics, Medical Research Council National Institute for Medical Research, Mill Hill, London NW7 1AA, UK.
authors.forename: Nadège
authors.initials: N
authors.lastname: Vernet
authors.forename: Shantha K
authors.initials: SK
authors.lastname: Mahadevaiah
authors.forename: Obah A
authors.initials: OA
authors.lastname: Ojarikre
authors.forename: Guy
authors.initials: G
authors.lastname: Longepied
authors.forename: Haydn M
authors.initials: HM
authors.lastname: Prosser
authors.forename: Allan
authors.initials: A
authors.lastname: Bradley
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mitchell
authors.forename: Paul S
authors.initials: PS
authors.lastname: Burgoyne
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D023902:Chromosome Pairing / Q000502:physiology*; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique; D006652:Histological Techniques; D020287:In Situ Nick-End Labeling; D008297:Male; D008540:Meiosis / Q000502:physiology*; D008677:Metaphase / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D010053:Ovary / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D012730:Sex Chromosomes / Q000235:genetics; D051876:Sex-Determining Region Y Protein / Q000235:genetics; D013090:Spermatocytes / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D019076:Transgenes / Q000235:genetics
chemical_list: D017931:DNA Primers; D004268:DNA-Binding Proteins; D051876:Sex-Determining Region Y Protein; C497746:Sry protein, mouse; D014157:Transcription Factors; C501342:Zfy1 protein, mouse; C501343:Zfy2 protein, mouse