ER whorls triggered by GhCNX6 were discovered involved in drought stress on cotton

Abstract

Drought stress is the main abiotic stress causing damage to cotton growth and severe yield loss. Under environmental stress conditions, the endoplasmic reticulum (ER) folding environment is disturbed, resulting in the accumulation of unfolded/misfolded proteins, causing ER stress and triggering the unfolded protein response (UPR). Analysis of drought RNA-sequencing data revealed a Gh_D09G2402.1 ( GhCNX ) gene involved in ER protein processing. Through the observation of the ultrastructure of the ER under drought stress in cotton, the characteristic structure of the endoplasmic reticulum whorl was found. Virus-induced gene silencing (VIGS) mediated GhCNX6 silenced cotton plants were found highly sensitive to drought stress. Arabidopsis thaliana plants overexpressing GhCNX6 showed stronger tolerance to drought stress, indicating that the GhCNX6 gene is involved in the action mechanism of cotton drought stress and enhances the tolerance to drought stress. Drought stress leads to ER stress response, and the resulting ER whorl and CNX gene play a role in the ER protein processing pathway, thereby regulating the mechanism of cotton response to drought stress. This study will help to further explore the mechanism of cotton drought resistance. • Endoplasmic reticulum whorls found in cotton under drought stress. • First preliminary verification of GhCNX6 positively responding to drought stress. • The regulatory mechanism of GhCNX6 and ER whorls under drought stress.