PAP- and GLD-2-type poly(A) polymerases are required sequentially in cytoplasmic polyadenylation and oogenesis in Drosophila.
Cytoplasmic polyadenylation has an essential role in activating maternal mRNA translation during early development. In vertebrates, the reaction requires CPEB, an RNA-binding protein and the poly(A) polymerase GLD-2. GLD-2-type poly(A) polymerases form a family clearly distinguishable from canonical poly(A) polymerases (PAPs). In Drosophila, canonical PAP is involved in cytoplasmic polyadenylation with Orb, the Drosophila CPEB, during mid-oogenesis. We show that the female germline GLD-2 is encoded by wispy. Wispy acts as a poly(A) polymerase in a tethering assay and in vivo for cytoplasmic polyadenylation of specific mRNA targets during late oogenesis and early embryogenesis. wispy function is required at the final stage of oogenesis for metaphase of meiosis I arrest and for progression beyond this stage. By contrast, canonical PAP acts with Orb for the earliest steps of oogenesis. Both Wispy and PAP interact with Orb genetically and physically in an ovarian complex. We conclude that two distinct poly(A) polymerases have a role in cytoplasmic polyadenylation in the female germline, each of them being specifically required for different steps of oogenesis.
Benoit
Perrine
P
mRNA Regulation and Development, Institut de Génétique Humaine, CNRS UPR 1142, 141 rue de la Cardonille, 34396 Montpellier Cedex 5, France.
Papin
Catherine
C
Kwak
Jae Eun
JE
Wickens
Marvin
M
Simonelig
Martine
M
D000818:Animals; D015153:Blotting, Western; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004330:Drosophila / Q000235:genetics* / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D005136:Eye Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D018507:Gene Expression Regulation, Developmental; D047468:Immunoprecipitation; D008540:Meiosis / Q000235:genetics; D008677:Metaphase / Q000235:genetics; D009866:Oogenesis / Q000235:genetics*; D026723:Polyadenylation / Q000235:genetics*; D011062:Polynucleotide Adenylyltransferase / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism
D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; D005136:Eye Proteins; D016601:RNA-Binding Proteins; C577503:cort protein, Drosophila; C089932:orb protein, Drosophila; C422624:skd protein, Drosophila; D011062:Polynucleotide Adenylyltransferase