January 6, 2021
Journal Article

Distinct Preflowering Drought Tolerance Strategies of Sorghum bicolor Genotype RTx430 Revealed by Subcellular Protein Profiling

Shadan Abdali
Kristin Engbrecht

Abstract

Drought is the largest stress affecting agricultural crops, resulting in substantial reductions in yield. Plant adaptation to water stress is a complex trait involving changes in hormone signaling, physiology, and morphology. Sorghum [Sorghum bicolor (L.) Moench] is a C4 cereal grass, agricultural staple, and is particularly drought tolerant. To better understand drought adaptation strategies, we compared the cytosolic- and organelle-enriched protein profiles of leaves from two Sorghum bicolor genotypes, RTx430 and BTx642, with differing pre-flowering drought tolerances after 8-weeks of growth under water limitation in the field. In agreement with previous findings, we observed significant drought-induced changes in the abundance of multiple heat shock proteins and dehydrins in both genotypes. Interestingly, our data suggests a larger genotype-specific drought response in protein profiles of organelles, while cytosolic responses are largely similar between genotypes. Organelle-enriched proteins whose abundance significantly changed exclusively in the pre-flowering drought tolerant genotype RTx430 upon drought stress suggest multiple mechanisms of drought tolerance. These include an RTx430-specific change in proteins associated with ABA metabolism and signal transduction, Rubisco activation, ROS scavenging, flowering-time regulation, and epicuticular wax production. We discuss the current understanding of these processes in relation to drought tolerance and their potential implications.

Revised: January 6, 2021 | Published: December 2, 2020

Citation

Ogden A.J., S.H. Abdali, K.M. Engbrecht, M. Zhou, and P. Handakumbura. 2020. "Distinct Preflowering Drought Tolerance Strategies of Sorghum bicolor Genotype RTx430 Revealed by Subcellular Protein Profiling." International Journal of Molecular Sciences 21, no. 24:Article No. 9706. PNNL-SA-157472. doi:10.3390/ijms21249706