A defined sequence within the 3' UTR of the areA transcript is sufficient to mediate nitrogen metabolite signalling via accelerated deadenylation.
Nitrogen metabolism in Aspergillus nidulans is regulated by AREA, a member of the GATA family of transcription factors. One mechanism that modulates AREA activity involves the rapid degradation of the areA transcript when sufficient NH4+ or Gln are available. This signalling mechanism has been shown to require a region of 218 nucleotides within the 3' untranslated region of areA mRNA. We demonstrate that this region functions independently in a heterologous transcript and acts to accelerate degradation of the poly(A) tail, which in turn leads to rapid transcript degradation in response to the addition of NH4+ or Gln to the growth medium. areA transcript degradation is inhibited by cycloheximide, but this is not a general consequence of translational inhibition. We believe that this is the first reported example in which specific physiological signals, acting through a defined sequence within a transcript, have been shown to promote accelerated poly(A) degradation, which in turn triggers transcript degradation.
Morozov
I Y
IY
Plant Science and Fungal Molecular Biology Research Group, School of Biological Sciences, Donnan Laboratories, The University of Liverpool, Crown Street, Liverpool L69 7ZD, UK.
Martinez
M G
MG
Jones
M G
MG
Caddick
M X
MX
D020413:3' Untranslated Regions; D001233:Aspergillus nidulans / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003513:Cycloheximide / Q000494:pharmacology; D004269:DNA, Bacterial; D005656:Fungal Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism*; D011061:Poly A; D014176:Protein Biosynthesis; D012329:RNA, Bacterial; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics*
D020413:3' Untranslated Regions; C079728:AreA protein, Aspergillus nidulans; D004269:DNA, Bacterial; D005656:Fungal Proteins; D012329:RNA, Bacterial; D014157:Transcription Factors; D011061:Poly A; D003513:Cycloheximide; D009584:Nitrogen