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Title: DRO1 influences root system architecture in Arabidopsis and Prunus species
Summary

Roots provide essential uptake of water and nutrients from the soil, as well as anchorage and stability for the whole plant. Root orientation, or angle, is an important component of the overall architecture and depth of the root system; however, little is known about the genetic control of this trait. Recent reports inOryza sativa(rice) identified a role forDEEPER ROOTING 1(DRO1) in influencing the orientation of the root system, leading to positive changes in grain yields under water‐limited conditions. Here we found thatDRO1andDRO1‐related genes are present across diverse plant phyla, and fall within theIGTgene family. TheIGTfamily also includesTAC1andLAZY1, which are known to affect the orientation of lateral shoots. Consistent with a potential role in root development,DRO1homologs in Arabidopsis and peach showed root‐specific expression. Promoter–reporter constructs revealed thatAtDRO1is predominantly expressed in both the root vasculature and root tips, in a distinct developmental pattern. Mutation ofAtDRO1led to more horizontal lateral root angles. Overexpression ofAtDRO1under a constitutive promoter resulted in steeper lateral root angles, as well as shoot phenotypes including upward leaf curling, shortened siliques and narrow lateral branch angles. A conserved C‐terminalEAR‐like motif found inIGTgenes was required for these ectopic phenotypes. Overexpression ofPpeDRO1inPrunus domestica(plum) led to deeper‐rooting phenotypes. Collectively, these data indicate a potential application forDRO1‐related genes to alter root architecture for drought avoidance and improved resource use.

 
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PAR ID:
10027011
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
89
Issue:
6
ISSN:
0960-7412
Page Range / eLocation ID:
p. 1093-1105
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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