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  • The dicot homolog of maize PPR103 carries a C-terminal DYW domain and may have a role in C-to-U editing of some chloroplast RNA transcripts
Title: The dicot homolog of maize PPR103 carries a C-terminal DYW domain and may have a role in C-to-U editing of some chloroplast RNA transcripts
Abstract In plants, cytidine-to-uridine (C-to-U) editing is a crucial step in processing mitochondria- and chloroplast-encoded transcripts. This editing requires nuclear-encoded proteins including members of the pentatricopeptide (PPR) family, especially PLS-type proteins carrying the DYW domain.IPI1/emb175/PPR103is a nuclear gene encoding a PLS-type PPR protein essential for survival inArabidopsis thalianaand maize. Arabidopsis IPI1 was identified as likely interacting with ISE2, a chloroplast-localized RNA helicase associated with C-to-U RNA editing in Arabidopsis and maize. Notably, while the Arabidopsis andNicotianaIPI1 orthologs possess complete DYW motifs at their C-termini, the maize homolog, ZmPPR103, lacks this triplet of residues which are essential for editing. In this study we examined the function of IPI1 in chloroplast RNA processing inN. benthamianato gain insight into the importance of the DYW domain to the function of the EMB175/PPR103/ IPI1 proteins. Structural predictions suggest that evolutionary loss of residues identified as critical for catalyzing C-to-U editing in other members of this class of proteins, were likely to lead to reduced or absent editing activity in theNicotianaand Arabidopsis IPI1 orthologs. Virus-induced gene silencing ofNbIPI1led to defects in chloroplast ribosomal RNA processing and changes to stability ofrpl16transcripts, revealing conserved function with its maize ortholog.NbIPI1-silenced plants also had defective C-to-U RNA editing in several chloroplast transcripts, a contrast from the finding that maize PPR103 had no role in editing. The results indicate that in addition to its role in transcript stability, NbIPI1 may contribute to C-to-U editing inN. benthamianachloroplasts.  more » « less
Award ID(s):
2210127
PAR ID:
10497167
Author(s) / Creator(s):
; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Plant Molecular Biology
Volume:
114
Issue:
2
ISSN:
0167-4412
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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