Antagonistic Regulation by CPN60A and CLPC1 of TRXL1 that Regulates MDH Activity Leading to Plant Disease Resistance and Thermotolerance

Progress in Research on the Mechanisms Underlying Chloroplast-Involved Heat Tolerance in Plants

“…Through continuous in-depth research, we believe that more molecular mechanisms underlying the chloroplast’s involvement in plant heat resistance will be elucidated, and more ways of improving the heat tolerance of plants through chloroplasts or chloroplast proteins will be discovered. Current research shows that increasing the abundance of proteins such as HSPs, TRXL1, SNAT, and GPAT in chloroplasts improves the heat tolerance of plants without causing significant defects in plant growth or development [ 58 , 71 , 73 , 76 ]. Future studies should also explore the detailed mechanism and the contributions of these or more genes to crop heat resistance, strive to find natural or induced mutants of these genes in crops, and find good heat-resistant materials for crop breeding.…”

“…First, the plastid proteins that can suppress or scavenge ROS may contribute to plant heat tolerance. For example, chloroplast TRXL1 is reduced, is partly degraded, and alters its chloroplast localization under heat stress conditions [ 71 ]. TRXL1 positively regulates malate levels via activation of NADP-dependent malate dehydrogenase (NADP-MDH) to suppress ROS formation.…”

“…Therefore, it has the ability to regulate heat tolerance and the disease resistance of plants. TRXL1 is degraded by the CLP protease complex and is protected by chaperonin CPN60A [ 71 ]. When Arabidopsis overexpressed ascorbate peroxidase (APX) from the heat-tolerant red algae Cyanidioschyzon merolae , it localized to the chloroplast stroma and significantly improved the ROS scavenging and heat resistance of Arabidopsis [ 72 ].…”

Protocol for determining protein cysteine thiol redox status using western blot analysis

“…The protocol below describes the specific steps for detection of reduced or oxidized status of protein cysteine-thiols. We have used this protocol to determine the redox state of Thioredoxin like 1 ( TRXL1 ) protein in plants grown under normal condition or subjected to abiotic and biotic stress for various time points ( Pant et al., 2020 ). Oxidation-reduction of regulatory proteins and metabolic enzymes containing cysteine thiols leads to formation or breakage of disulfide bond causing changes in protein conformation, folding, monomerization or oligomerization or complex formation ( Chung et al., 2013 ; Rouhier et al., 2015 ; Waszczak et al., 2015 ).…”

“…This protocol can be successfully applied to other biological sources. For complete details on the use and execution of this protocol, please refer to Pant et al. (2020) .…”