Expression of a vas::EGFP transgene in primordial germ cells of the zebrafish.
In zebrafish, maternally produced vasa (vas) transcripts become targeted to the cleavage planes of early embryos and subsequently incorporated into the primordial germ cells (PGCs). Zygotic vas transcription occurs from the onset of gastrulation. Here, we report on the characterisation of the zebrafish vas locus. The gene consists of 27 exons, spans about 25kb, and contains two CpG-rich regions. We have used vas regulatory regions to establish transgenic zebrafish lines expressing enhanced green fluorescent protein (EGFP) in their PGCs. Maternally encoded vas::EGFP transcripts and VAS::EGFP protein segregate with the PGCs during embryogenesis. We find that the maternally deposited vas::EGFP transcripts are stable during embryogensis at least up to 50h of development. Vas::EGFP transcripts could not be detected in embryos that inherit the transgene from males, most likely due to the lack of one or more regulatory elements required for early zygotic expression. We show that vas::EGFP transcripts become enriched to the cleavage planes in early embryos, a finding that supported an RNA localisation signal localised within the vas region of these transcripts.
Sars International Centre for Marine Molecular Biology, Bergen High Technology Centre, Thormøhlensgt. 55, Norway.
Anne Vatland
AV
Krøvel
Lisbeth Charlotte
LC
Olsen
D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D053487:DEAD-box RNA Helicases; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D005822:Genetic Vectors; D005854:Germ Cells / Q000378:metabolism; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics; D008297:Male; D011401:Promoter Regions, Genetic; D012313:RNA / Q000235:genetics / Q000378:metabolism; D020365:RNA Helicases / Q000235:genetics*; D020871:RNA Stability; D015027:Zebrafish / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029961:Zebrafish Proteins
D018076:DNA, Complementary; D008164:Luminescent Proteins; D029961:Zebrafish Proteins; D049452:Green Fluorescent Proteins; D012313:RNA; C498289:ddx4 protein, zebrafish; D053487:DEAD-box RNA Helicases; D020365:RNA Helicases