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Title: Control of leaf blade outgrowth and floral organ development by LEUNIG , ANGUSTIFOLIA 3 and WOX transcriptional regulators
Summary

Plant lateral organ development is a complex process involving both transcriptional activation and repression mechanisms. TheWOXtranscriptional repressorWOX1/STF, theLEUNIG(LUG) transcriptional corepressor and theANGUSTIFOLIA3 (AN3) transcriptional coactivator play important roles in leaf blade outgrowth and flower development, but how these factors coordinate their activities remains unclear. Here we report physical and genetic interactions among these key regulators of leaf and flower development.

We developed a novelin plantatranscriptional activation/repression assay and suggest thatLUGcould function as a transcriptional coactivator during leaf blade development.

MtLUGphysically interacts with MtAN3, and this interaction appears to be required for leaf and flower development. A single amino acid substitution at position 61 in theSNHdomain of MtAN3 protein abolishes its interaction with MtLUG, and its transactivation activity and biological function. Mutations inlugandan3enhanced each other's mutant phenotypes. Both thelugand thean3mutations enhanced thewox1 prsleaf and flower phenotypes inArabidopsis.

Our findings together suggest that transcriptional repression and activation mediated by theWOX,LUGandAN3 regulators function in concert to promote leaf and flower development, providing novel mechanistic insights into the complex regulation of plant lateral organ development.

 
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NSF-PAR ID:
10453874
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
223
Issue:
4
ISSN:
0028-646X
Page Range / eLocation ID:
p. 2024-2038
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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