The R2R3 Myb transcription factor exhibits a wide range of functions and participates in various biological
processes in plant development, secondary metabolism, and abiotic stress tolerance, among others. Vitis Myb14
initially identified for its involvement in resveratrol synthesis in grapevines. In this study, we investigate its role
in abiotic stress tolerance. Significant differences in expression were observed between two grape varieties, Vitis
amurensis (Cold-hardy) and V. vinifera (Cold-sentitive), under abiotic and hormone treatments. Both VvMyb14
and VaMyb14 demonstrated responsiveness to cold, drought and high salt treatment, but VaMyb14 exhibited a
quicker and more pronounced response. To investigate further, we overexpressed VaMyb14 in A. thalina and
found that VaMyb14 OE plants showed significantly enhanced cold and drought tolerance compared to wild-type
plants. Additionally, the transgenic lines exhibited increased antioxidant enzyme activity, particularly POD ac_x0002_tivity, and reduced MDA content. Microarray analysis of VaMyb14 OE plants revealed up-regulation of several
ABA metabolism and signal transduction genes, including several LTPs, PP2Cs, RD29B, COR78 and other
structural genes, indicating that VaMyb14 has the capacity to reprogram a significant signaling pathway.
Furthermore, comparative mRNA sequencing profiling of 35S:VaMyb14 grapevine callus indicated its involvement its function involved in ROS scavenging and ABA signaling. These findings collectively demonstrate that
Vitis Myb14 serves as a critical regulator in grapevine stress responses, contributing to improved defense against
necrotrophic pathogens, enhanced phytoalexin resveratrol production, and increased drought or cold tolerance.
Copyright 2002 - 2023 Wuhan Botanical Garden,Chinese Academy Of
Sciences
Email: wbgoffice@wbgcas.cn ICP: 05004779-1
