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Title: Functions and mechanisms of A-to-I RNA editing in filamentous ascomycetes
Although lack of ADAR (adenosine deaminase acting on RNA) orthologs, genome-wide A-to-I editing occurs specifically during sexual reproduction in a number of filamentous ascomycetes, includingFusarium graminearumandNeurospora crassa. Unlike ADAR-mediated editing in animals, fungal A-to-I editing has a strong preference for hairpin loops and U at −1 position, which leads to frequent editing of UAG and UAA stop codons. Majority of RNA editing events in fungi are in the coding region and cause amino acid changes. Some of these editing events have been experimentally characterized for providing heterozygote and adaptive advantages inF.graminearum. Recent studies showed that FgTad2 and FgTad3, 2 ADAT (adenosine deaminase acting on tRNA) enzymes that normally catalyze the editing of A34 in the anticodon of tRNA during vegetative growth mediate A-to-I mRNA editing during sexual reproduction. Stage specificity of RNA editing is conferred by stage-specific expression of short transcript isoforms ofFgTAD2andFgTAD3as well as cofactors such asAME1andFIP5that facilitate the editing of mRNA in perithecia. Taken together, fungal A-to-I RNA editing during sexual reproduction is catalyzed by ADATs and it has the same sequence and structural preferences with editing of A34 in tRNA.  more » « less
Award ID(s):
1758434
PAR ID:
10522079
Author(s) / Creator(s):
; ; ;
Editor(s):
Xue, Chaoyang
Publisher / Repository:
PLOS
Date Published:
Journal Name:
PLOS Pathogens
Volume:
20
Issue:
6
ISSN:
1553-7374
Page Range / eLocation ID:
e1012238
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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