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Title: Xanthomonas translucens commandeers the host rate-limiting step in ABA biosynthesis for disease susceptibility
Plants are vulnerable to disease through pathogen manipulation of phytohormone levels, which otherwise regulate development, abiotic, and biotic responses. Here, we show that the wheat pathogen Xanthomonas translucens pv. undulosa elevates expression of the host gene encoding 9- cis -epoxycarotenoid dioxygenase ( TaNCED-5BS ), which catalyzes the rate-limiting step in the biosynthesis of the phytohormone abscisic acid and a component of a major abiotic stress-response pathway, to promote disease susceptibility. Gene induction is mediated by a type III transcription activator-like effector. The induction of TaNCED-5BS results in elevated abscisic acid levels, reduced host transpiration and water loss, enhanced spread of bacteria in infected leaves, and decreased expression of the central defense gene TaNPR1 . The results represent an appropriation of host physiology by a bacterial virulence effector.  more » « less
Award ID(s):
1741090
NSF-PAR ID:
10170441
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
116
Issue:
42
ISSN:
0027-8424
Page Range / eLocation ID:
20938 to 20946
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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