The study shows that the SnRK1 catalytic subunit KIN10 directs tissue-specific growth‑defense programs in Arabidopsis thaliana by reshaping transcriptomes. kin10 knockout mutants exhibit altered root transcription, reduced root growth, and weakened defense against Pseudomonas syringae, whereas KIN10 overexpression activates shoot defense pathways, increasing ROS and salicylic acid signaling at the cost of growth.
The study examined early metabolic responses to salt stress in a salt‑tolerant alfalfa cultivar, focusing on SnRK1 activity, sucrose, and trehalose‑6‑phosphate dynamics during leaf expansion. Hydroponically grown plants exposed to 200 mM NaCl showed rapid, wave‑like SnRK1 activation within 1 hour, a transient decline in chloroplast performance, and an uncoupling of the Tre6P‑sucrose regulatory link, with a second SnRK1 peak correlating with reduced leaf growth. Exogenous sucrose inhibited SnRK1 activity, highlighting early SnRK1 activation as a pivotal component of salt stress adaptation.
The study shows that silencing of NOR2 rRNA genes in Arabidopsis thaliana depends primarily on CHH-context cytosine methylation, particularly mediated by CMT2 and the chromatin remodeler DDM1, rather than CG or CHG methylation. Comparative promoter analysis revealed a prevalence of CHH sites in plant rDNA promoters, explaining why CHH methylation mutants disrupt NOR2 silencing more strongly, while NOR2 loci are hyper‑methylated and more condensed than NOR4.