title: Differential expression of boule and dazl in adult germ cells of the Asian seabass.
abstract: Fertility genes boule and dazl constitute the evolutionarily conserved DAZ (Deleted in AZoospermia) family of RNA binding proteins essential for germline development across animal phyla. Here we report the cloning and expression analysis of boule and dazl from the Asian seabass (Lates calcarifer), a marine fish that undergoes sequential male-to-female sex reversal. Molecular cloning and sequence comparison led to the identification of boule and dazl cDNAs. RT-PCR analysis showed that both boule and dazl RNAs were restricted to the gonads among adult organs examined. Chromogenic in situ hybridization revealed germ cell-specific expression for both boule and dazl in female and male adults. Importantly, distinct differences were found between boule and dazl in terms of temporospatial expression and subcellular distribution. The boule RNA was abundant in late gametogenic cells except sperm. Interestingly, dazl expression increases in early oocytes and concentrates in a perinuclear speckle that appears to develop ultimately into the Balbiani body in advanced oocytes. The dazl RNA was found to be abundant in spermatocytes but hardly detectable in sperm. These data demonstrate that boule and dazl are germ cell markers in the adult Asian seabass, and that bisexual germline-specific expression has been conserved for boule and dazl in fish.
authors.affiliation: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore.
authors.forename: Manali
authors.initials: M
authors.lastname: Dwarakanath
authors.affiliation: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore.
authors.forename: Menghuat
authors.initials: M
authors.lastname: Lim
authors.affiliation: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Xu
authors.affiliation: Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore. Electronic address: dbshyh@nus.edu.sg.
authors.forename: Yunhan
authors.initials: Y
authors.lastname: Hong
mesh_terms: D053687:Adult Stem Cells / Q000378:metabolism; D000818:Animals; D001492:Bass / Q000235:genetics* / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D005260:Female; D029941:Fish Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D005786:Gene Expression Regulation; D005854:Germ Cells / Q000378:metabolism*; D006066:Gonads / Q000378:metabolism; D008297:Male; D010802:Phylogeny; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D012741:Sexual Maturation / Q000235:genetics; D059467:Transcriptome
chemical_list: D015415:Biomarkers; D029941:Fish Proteins; D016601:RNA-Binding Proteins
keywords: Asian seabass; Balbiani body; Gametogenesis; boule; dazl