Transcriptome Reveals the Molecular Mechanism of the ScALDH21 Gene from the Desert Moss Syntrichia caninervis Conferring Resistance to Salt Stress in Cotton

Abstract

The desert moss Syntrichia caninervis has proven to be an excellent plant material for mining resistance genes. The aldehyde dehydrogenase 21 (ScALDH21) gene from S. caninervis has been shown to confer tolerance to salt and drought, but it is unclear how the transgene ScALDH21 regulates tolerance to abiotic stresses in cotton. In the present work, we studied the physiological and transcriptome analyses of non-transgenic (NT) and transgenic ScALDH21 cotton (L96) at 0 day, 2 days, and 5 days after salt stress. Through intergroup comparisons and a weighted correlation network analysis (WGCNA), we found that there were significant differences between NT and L96 cotton in the plant hormone, Ca2+, and mitogen-activated protein kinase (MAPK) signaling pathways as well as for photosynthesis and carbohydrate metabolism. Overexpression of ScALDH21 significantly increased the expression of stress-related genes in L96 compared to NT cotton under both normal growth and salt stress conditions. These data suggest that the ScALDH21 transgene can scavenge more reactive oxygen species (ROS) in vivo relative to NT cotton and improve cotton resistance to salt stress by increasing the expression of stress-responsive genes, responding quickly to stress stimuli, enhancing photosynthesis and improving carbohydrate metabolism. Therefore, ScALDH21 is a promising candidate gene to improve resistance to salt stress, and the application of this gene in cotton provides new insights into molecular plant breeding.

Roles of S-Adenosylmethionine and Its Derivatives in Salt Tolerance of Cotton

“…Cotton WRKY transcription factor GhWRKY17 can improve the salt sensitivity of transgenic tobacco through ABA signal transduction and regulation of ROS production in plant cells [62]. Under salt stress conditions, the aldehyde dehydrogenase 21 gene (ScALDH21) of S. canadensis can scavenge excessive ROS in transgenic cotton, thereby improving the salt tolerance of cotton [63]. Silencing the Raf-like MAPKKK gene GhRaf 19 reduced the accumulation of ROS in cotton, thereby improving the tolerance of plants to salt stress [64].…”

Characterization and gene expression patterns analysis implies BSK family genes respond to salinity stress in cotton

“…So far, there have been no reports on the functional studies of cotton BSKs genes in hormone signal transduction, growth and development, and response to stress. The expression level of two BSKs in transgenic ScALDH21 cotton was higher than that of non-transgenic cotton under salt stress ( Yang et al, 2023 ). Overexpression of BSKs in crops such as rice and maize has been found to enhance salt tolerance ( Li et al, 2022 ; Liu et al, 2022 ; Zhang et al, 2022 ).…”