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  • A witches' broom phytoplasma effector induces stunting by stabilizing a bHLH transcription factor in Ziziphus jujuba plants

This content will become publicly available on July 1, 2026

Title: A witches' broom phytoplasma effector induces stunting by stabilizing a bHLH transcription factor in Ziziphus jujuba plants
Summary Phytoplasmas are specialized phloem‐limited bacteria that cause diseases on various crops, resulting in significant agricultural losses. This research focuses on the jujube witches' broom (JWB) phytoplasma and investigates the host‐manipulating activity of the effector SJP39.We found that SJP39 directly interacts with the plant transcription factor bHLH87 in the nuclei. SJP39 stabilizes the bHLH87 homologs inArabidopsis thalianaand jujube, leading to growth defects in the plants.Transcriptomic analysis indicates that SJP39 affects the gibberellin (GA) pathway in jujube. We further demonstrate that ZjbHLH87 regulates GA signaling as a negative regulator, and SJP39 enhances this regulation.The research offers important insights into the pathogenesis of JWB disease and identified SJP39 as a virulence factor that can contribute to the growth defects caused by JWB phytoplasma infection. These findings open new opportunities to manage JWB and other phytoplasma diseases.  more » « less
Award ID(s):
1942949
PAR ID:
10659061
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
New Phytologist
Date Published:
Journal Name:
New Phytologist
Volume:
247
Issue:
1
ISSN:
0028-646X
Page Range / eLocation ID:
249 to 264
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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