AUTHOR=He HuaJie , Zhang YuZheng , Wen BinBin , Meng XiangGuang , Wang Ning , Sun MingYun , Zhang Rui , Zhao XueHui , Tan QiuPing , Xiao Wei , Li DongMei , Fu XiLing , Chen XiuDe , Li Ling 

TITLE=PpNUDX8, a Peach NUDIX Hydrolase, Plays a Negative Regulator in Response to Drought Stress

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 12 - 2021

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.831883

DOI=10.3389/fpls.2021.831883

ISSN=1664-462X

ABSTRACT=Drought stress is a serious abiotic stress source that affects the growth and fruit quality of peach trees. However, the molecular mechanism of the NUDIX hydrolase family in peaches in response to drought stress is still unclear. Here, we isolated and identified the PpNUDX8 gene from the peach NUDIX hydrolase family, and found that PpNUDX8 has a typical NUDIX hydrolase domain.In this study, we performed PEG6000 drought treatment on peach seedlings, and qRT–PCR analysis showed that PEG6000 induced the transcription level of PpNUDX8. Overexpression of PpNUDX8 reduced the tolerance of calli to PEG6000 treatment. Compared with wild-type apple calli, PpNUDX8 transgenic apple calli had a lower fresh weight and higher MDA content.Under drought stress, PpNUDX8 transgenic tobacco had a greater degree of wilting and shorter primary roots than under normal conditions. The chlorophyll, soluble protein, and proline contents in the transgenic tobacco decreased, and the MDA content and relative conductivity increased.At the same time, PpNUDX8 negatively regulates ABA signal transduction and is not sensitive to ABA performance. Overexpression of PpNUDX8 reduces the expression of the ABA synthesis-related gene NCED6 and increases the expression of the ABA decomposition-related gene CYP1 in tobacco, which in turn leads to a decrease in the ABA content in tobacco.In addition, under normal conditions, overexpression of PpNUDX8 destroyed the homeostasis of NAD and NADH in tobacco. After drought stress, the changes in NAD and NADH in PpNUDX8 transgenic tobacco were more severe than those in WT tobacco. In addition, PpNUDX8 also interacted with PpSnRk1γ.