Poly(A)-independent regulation of maternal hunchback translation in the Drosophila embryo.
Development of the Drosophila abdomen requires repression of maternal hunchback (hb) mRNA translation in the posterior of the embryo. This regulation involves at least four components: nanos response elements within the hb 3' untranslated region and the activities of Pumilio (PUM), Nanos (NOS), and Brain tumor. To study this regulation, we have developed an RNA injection assay that faithfully recapitulates the regulation of the endogenous hb message. Previous studies have suggested that NOS and PUM can regulate translation by directing poly(A) removal. We have found that RNAs that lack a poly(A) tail and cannot be polyadenylated and RNAs that contain translational activating sequences in place of the poly(A) tail are still repressed in the posterior. These data demonstrate that the poly(A) tail is not required for regulation and suggest that NOS and PUM can regulate hb translation by two mechanisms: removal of the poly(A) tail and a poly(A)-independent pathway that directly affects translation.
Chagnovich
D
D
Developmental Genetics Program, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, and Howard Hughes Medical Institute, New York, NY 10016, USA.
Lehmann
R
R
D020413:3' Untranslated Regions / Q000235:genetics; D000818:Animals; D030801:Animals, Genetically Modified; D003063:Cnidaria / Q000201:enzymology / Q000235:genetics; D001517:Coleoptera; D004268:DNA-Binding Proteins / Q000235:genetics*; D004330:Drosophila / Q000196:embryology* / Q000235:genetics*; D029721:Drosophila Proteins; D004625:Embryo, Nonmammalian / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D016147:Genes, Tumor Suppressor; D018392:Genomic Imprinting; D019476:Insect Proteins / Q000235:genetics; D008156:Luciferases / Q000032:analysis / Q000235:genetics; D008297:Male; D009024:Morphogenesis; D011061:Poly A / Q000235:genetics*; D012315:RNA Caps / Q000235:genetics; D016601:RNA-Binding Proteins; D014157:Transcription Factors / Q000235:genetics*; D016335:Zinc Fingers
D020413:3' Untranslated Regions; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D012315:RNA Caps; D016601:RNA-Binding Proteins; D014157:Transcription Factors; C412783:brat protein, Drosophila; C061245:hb protein, Drosophila; C074333:pum protein, Drosophila; C070574:nos protein, Drosophila; D011061:Poly A; D008156:Luciferases