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Title: Diacylglycerol kinase and associated lipid mediators modulate rice root architecture
Summary

Diacylglycerol kinase (DGK) phosphorylates diacylglycerol (DAG) to generate phosphatidic acid (PA), and bothDAGandPAare lipid mediators in the cell. Here we show thatDGK1 in rice (Oryza sativa) plays important roles in root growth and development.

Two independentOsDGK1‐knockout (dgk1) lines exhibited a higher density of lateral roots (LRs) and thinner seminal roots (SRs), whereasOsDGK1‐overexpressing plants displayed a lowerLRdensity and thickerSRsthan wild‐type (WT) plants.

Overexpression ofOsDGK1led to a decline in theDGKsubstrateDAGwhereas specificPAspecies decreased indgk1roots. Supplementation ofDAGtoOsDGK1‐overexpressing seedlings restored theLRdensity andSRthickness whereas application ofPAtodgk1seedlings restored theLRdensity andSRthickness to those of theWT. In addition, treatment of rice seedlings with theDGKinhibitor R59022 increased the level ofDAGand decreasedPA, which also restored the root phenotype ofOsDGK1‐overexpressing seedlings close to that of theWT.

Together, these results indicate thatDGK1 and associated lipid mediators modulate rice root architecture;DAGpromotesLRformation and suppressesSRgrowth whereasPAsuppressesLRnumber and promotesSRthickness.

 
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NSF-PAR ID:
10377673
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
223
Issue:
1
ISSN:
0028-646X
Page Range / eLocation ID:
p. 261-276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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