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  • Overexpression of two CDPKs from wild Chinese grapevine enhances powdery mildew resistance in Vitis vinifera and Arabidopsis
Title: Overexpression of two CDPKs from wild Chinese grapevine enhances powdery mildew resistance in Vitis vinifera and Arabidopsis
Summary

Calcium‐dependent protein kinases (CDPKs) play vital roles in metabolic regulations and stimuli responses in plants. However, little is known about their function in grapevine.

Here, we report thatVpCDPK9andVpCDPK13, two paralogousCDPKsfromVitis pseudoreticulataaccession Baihe‐35‐1, appear to positively regulate powdery mildew resistance. The transcription of them in leaves of ‘Baihe‐35‐1’ were differentially induced upon powdery mildew infection. Overexpression ofVpCDPK9‐YFPorVpCDPK13‐YFPin theV. viniferasusceptible cultivar Thompson Seedless resulted in enhanced resistance to powdery mildew (YFP, yellow fluorescent protein). This might be due to elevation of SA and ethylene production, and excess accumulation of H2O2and callose in penetrated epidermal cells and/or the mesophyll cells underneath.

Ectopic expression ofVpCDPK9‐YFPin Arabidopsis resulted in varied degrees of reduced stature, pre‐mature senescence and enhanced powdery mildew resistance. However, these phenotypes were abolished inVpCDPK9‐YFPtransgenic lines impaired in SA signaling (pad4sid2) or ethylene signaling (ein2). Moreover, both of VpCDPK9 and VpCDPK13 were found to interact with and potentially phosphorylate VpMAPK3, VpMAPK6, VpACS1 and VpACS2in vivo(ACS, 1‐aminocyclopropane‐1‐carboxylic acid (ACC) synthase; MAPK, mitogen‐activated protein kinase).

These results suggest thatVpCDPK9andVpCDPK13contribute to powdery mildew resistance via positively regulating SA and ethylene signaling in grapevine.

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Award ID(s):
1901566
NSF-PAR ID:
10451992
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
230
Issue:
5
ISSN:
0028-646X
Page Range / eLocation ID:
p. 2029-2046
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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