title: Expression of meiotic genes in the germline progenitors of Drosophila embryos.
abstract: Meiosis is one of the fundamental characteristics of germ cells. In Drosophila, genetic screens have identified many genes required for meiotic division. However, it remains elusive as to when and how these meiotic genes are activated during germline development. To obtain insights into their regulatory mechanisms, we examined the expression of 38 meiotic genes in the germline progenitors, pole cells, during embryogenesis. We found that the transcripts of 12 meiotic genes were enriched in pole cells within the embryonic gonads. Among them, bag of marbles (bam), benign gonial cell neoplasia (bgcn), deadhead (dhd), matotopetli (topi) and twine (twe) were activated only in pole cells within the gonads, whereas the transcripts from grapes (grp), Kinesin-like protein at 3A (Klp3A), pavarotti (pav), lesswright (lwr), mei-P26, Topoisomerase 2 (Top2) and out at first (oaf) were distributed ubiquitously in early embryos and then became restricted to pole cells and to a subset of somatic tissues at later embryonic stages. The remaining meiotic genes were either expressed ubiquitously in the embryos (15 genes) or were undetectable in pole cells within the gonads (11 genes). These observations suggest that pole cells have already acquired the potential to express several meiotic genes. Our data will thus provide a useful basis for analyzing how the germline acquires a potential to execute meiosis.
authors.affiliation: Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, Higashiyama, Myodaiji, Okazaki 444-8787, Japan. mmukai@nibb.ac.jp
authors.forename: Masanori
authors.initials: M
authors.lastname: Mukai
authors.forename: Yu
authors.initials: Y
authors.lastname: Kitadate
authors.forename: Kayo
authors.initials: K
authors.lastname: Arita
authors.forename: Shuji
authors.initials: S
authors.lastname: Shigenobu
authors.forename: Satoru
authors.initials: S
authors.lastname: Kobayashi
mesh_terms: D000818:Animals; D000071877:Checkpoint Kinase 1; D004330:Drosophila / Q000166:cytology / Q000196:embryology* / Q000235:genetics*; D029721:Drosophila Proteins; D004625:Embryo, Nonmammalian; D020224:Expressed Sequence Tags; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D005854:Germ Cells / Q000378:metabolism*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008540:Meiosis / Q000235:genetics*; D014018:Tissue Distribution
chemical_list: D029721:Drosophila Proteins; D000071877:Checkpoint Kinase 1; C000605877:grp protein, Drosophila