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Title: An RNA exosome subunit mediates cell-to-cell trafficking of a homeobox mRNA via plasmodesmata
Messenger RNAs (mRNAs) function as mobile signals for cell-to-cell communication in multicellular organisms. The KNOTTED1 (KN1) homeodomain family transcription factors act non–cell autonomously to control stem cell maintenance in plants through cell-to-cell movement of their proteins and mRNAs through plasmodesmata; however, the mechanism of mRNA movement is largely unknown. We show that cell-to-cell movement of a KN1 mRNA requires ribosomal RNA–processing protein 44A (AtRRP44A), a subunit of the RNA exosome that processes or degrades diverse RNAs in eukaryotes. AtRRP44A can interact with plasmodesmata and mediates the cell-to-cell trafficking of KN1 mRNA, and genetic analysis indicates that AtRRP44A is required for the developmental functions of SHOOT MERISTEMLESS, an Arabidopsis KN1 homolog. Our findings suggest that AtRRP44A promotes mRNA trafficking through plasmodesmata to control stem cell–dependent processes in plants.  more » « less
Award ID(s):
1930101
NSF-PAR ID:
10339647
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Science
Volume:
375
Issue:
6577
ISSN:
0036-8075
Page Range / eLocation ID:
177 to 182
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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