AUTHOR=Zang Dandan , Sun Yan , Zhao Hengtian 

TITLE=Transcriptional regulatory cascade of LcMYB71 and LcNAC73 affects low-temperature and drought stress response in Lonicera caerulea

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1288947

DOI=10.3389/fpls.2023.1288947

ISSN=1664-462X

ABSTRACT=<p>The development of stress tolerance is regulated via the transcriptional regulatory networks involving regulatory homeostasis mediated by protein–DNA interactions. <italic>LcNAC73</italic> from <italic>Lonicera caerulea</italic> was characterized to understand the underlying mechanism of low-temperature and drought stress response in <italic>L. caerulea</italic>. To better understand the transcription pathway of <italic>LcNAC73</italic>, we cloned the promoter and screened proteins that could interact with the promoter. Using Yeast one-hybrid, electrophoretic mobility shift, and chromatin immunoprecipitation assays, we found that the LcMYB71 protein specifically bound to the promoter of <italic>LcNAC73</italic>. The transient transformation and stable transgenic system were used to produce transgenic <italic>L. caerulea</italic> plants with overexpressed and silenced <italic>LcNAC73</italic>, elucidating the effect of <italic>LcNAC73</italic> on low-temperature and drought stress tolerance. <italic>LcNAC73</italic> positively regulated the proline content and enhanced the scavenging of reactive oxygen species, thus improving tolerance to low-temperature and drought stress. Further studies revealed that <italic>LcMYB71</italic> and <italic>LcNAC73</italic> had similar functions and could improve plant low-temperature and drought tolerance. It is necessary to identify the upstream regulators of a specific gene to characterize gene functions and the associated transcriptional pathways.</p>