Modulation of cell cycle progression and chromatin dynamic as tolerance mechanisms to salinity and drought stress in maize

Abstract

Salinity and drought are the major abiotic stresses that disturb several aspects of maize plants growth at the cellular level, one of these aspects is cell cycle machinery.In our study, we dissected the molecular alterations and downstream effectors of salinity and drought stress on cell cycle regulation and chromatin remodeling. Effects of salinity and drought stress were determined on maize seedlings using 200 mM NaCl (induced salinity stress), and 250 mM mannitol (induced drought stress) treatments, then cell cycle progression and chromatin remodeling dynamics were investigated. Seedlings displayed severe growth defects, including inhibition of root growth. Interestingly, stress treatments induced cell cycle arrest in S-phase with extensive depletion of cyclins B1 and A1. Further investigation of gene expression profiles of cell cycle regulators showed the downregulation of the CDKA, CDKB, CYCA, and CYCB. These results reveal the direct link between salinity and drought stress and cell cycle deregulation leading to a low cell proliferation rate. Moreover, abiotic stress alters chromatin remodeling dynamic in a way that directs the cell cycle arrest. We observed low DNA methylation patterns accompanied by dynamic histone modifications that favor chromatin decondensation. Also, the high expression of DNA topoisomerase 2, 6 family was detected as consequence of DNA damage. In conclusion, in response to salinity and drought stress, maize seedlings exhibit modulation of cell cycle progression, resulting in the cell cycle arrest through chromatin remodeling.

Exogenous Application of Alpha-Lipoic Acid Mitigates Salt-Induced Oxidative Damage in Sorghum Plants through Regulation Growth, Leaf Pigments, Ionic Homeostasis, Antioxidant Enzymes, and Expression of Salt Stress Responsive Genes

“…Several studies have shown that salt stress can affect multiple morphological, physiological, biochemical, and molecular aspects of plants [6,17,40]. In this study, we observed that exposing plants to salt stress inhibited plant growth parameters, including plant height, fresh weight, dry weight, and leaf area as compared to the unstressed plants (Figure 1).…”

Seed Priming With an Animal-derived Protein Hydrolysate Improves Drought Tolerance of Tomato Seeds by Enhancing Reserve Mobilization, Osmotic Adjustment, and Antioxidant Mechanism

“…4a and b). Overproduction of ROS under abiotic stress usually leads to an oxidative damage to the cellular components, leading to membrane lipid peroxidation and cell membrane destruction (Kamal et al, 2021;Sasi et al, 2021;Sun et al, 2017). The MDA and Evans blue uptake are considered as key indicators of lipid peroxidation and integrity of the plasma membrane in plants to re ect the degree of membrane damage (Sun et al, 2017).…”

Plant CDKs—Driving the Cell Cycle through Climate Change

“…Under drought conditions, rice plants also showed a reduction in their growth with decreased height and shoot dry mass and a smaller number of leaves [ 171 ]. Under salt and water stress, the levels of CYCB1 , CYCA1 , and CDKA/CDKB in maize are drastically reduced [ 172 ], indicating an interruption in the cell cycle checking process performed by these two groups of cyclins and by the association with CDKA and CDKB [ 173 ] ( Figure 2 A).…”