The CCCH zinc finger protein PeC3H74 of Moso bamboo (Phyllostachys edulis) positively regulates drought and salinity tolerances in transgenic plants

Moso bamboo (Phyllostachys edulis) is one of the most important fast growing non-timber forest products in the world, drought and salinity are the main environmental factors limiting its growth and geographical distribution. CCCH zinc finger protein plays a key role in plant response to environmental stresses, but its functional role in Moso bamboo is poorly understood. Here, we found that Moso bamboo PeC3H74 strongly responds to drought and salt stress. PeC3H74 is a transcriptional activator, and it binds to the CT-rich motif. Overexpression of PeC3H74 enhanced ROS scavenging ability in transgenic Arabidopsis thaliana and Oryza sativa plants and improved the tolerance of transgenic plants to drought stress. Transcriptome analysis showed overexpression of PeC3H74 leading to activation of the ABA signaling and stress-related genes in transgenic plants. Overexpression of PeC3H74 reduced the transgenic plant's sensitivity to exogenous ABA. Meanwhile, yeast-one-hybrid and dual-luciferase assays showed that AtDSR1, an abiotic stress regulator of A. thaliana, may act as a downstream target gene of PeC3H74. More importantly, analysis of phenotypic and physiological indicators in transgenic plants showed that PeC3H74 also regulated the tolerance of transgenic A. thaliana and O. sativa plants to salt stress. Overall, our findings provide a key candidate gene for Moso bamboo molecular breeding for abiotic resistance.