Degradation of maternal string mRNA is controlled by proteins encoded on maternally contributed transcripts.
In Drosophila, maternal string mRNAs are stable for the first few hours of development, but undergo specific timed degradation at the cellularisation stage. To determine whether the proteins that control this degradation are maternally or zygotically transcribed, we have used in situ hybridisation to determine the fate of maternal string transcripts in mutant embryos which lack individual chromosome arms. Our data indicate that maternal string mRNA persists for the normal period in all these mutants. Using alpha-amanitin to inhibit zygotic transcription we have shown that degradation of maternal mRNA is unaffected. Therefore, the proteins required to activate the degradation of string mRNA are encoded on a maternally contributed mRNA. We discuss possible models to explain the degradation pathway.
Myers
F A
FA
Biophysics Laboratory, University of Portsmouth, UK.
Francis-Lang
H
H
Newbury
S F
SF
D000546:Amanitins / Q000494:pharmacology; D000818:Animals; D018797:Cell Cycle Proteins; D004330:Drosophila / Q000196:embryology / Q000235:genetics* / Q000378:metabolism*; D029721:Drosophila Proteins; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D008297:Male; D008954:Models, Biological; D009154:Mutation; D010749:Phosphoprotein Phosphatases / Q000235:genetics*; D017027:Protein Tyrosine Phosphatases; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects; D014960:X Chromosome
D000546:Amanitins; D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; D011506:Proteins; D012333:RNA, Messenger; D010749:Phosphoprotein Phosphatases; D017027:Protein Tyrosine Phosphatases; C059217:stg protein, Drosophila