Abstract
The imminent danger of global warming jeopardizes plant survival, leading to negative consequences for growth and agricultural productivity. A thorough understanding of how plants respond to heat stress at the molecular level is essential for the development of thermotolerant crops. To delve into this intricate mechanism, we embarked on exploring proteome dynamics in Arabidopsis thaliana seedlings under moderate heat stress conditions (30°C), employing an innovative blend of 15N-stable isotope labeling and the ProteinTurnover algorithm. This method enabled a meticulous examination of proteomic alterations across various cellular fractions. Our investigation unearthed significant turnover rate changes in 571 proteins, with a median increase of 1.4-fold, reflecting accelerated protein dynamics during heat stress. Notably, root soluble proteins displayed subtler changes, hinting at tissue-specific adaptations. We also observed remarkable turnover variations in proteins associated with redox signaling, stress response, and metabolism, underscoring the intricate nature of the response network. Conversely, proteins involved in carbohydrate metabolism and mitochondrial ATP synthesis exhibited minimal turnover changes, indicating their stability. This comprehensive analysis provides insights into the proteomic adjustments of Arabidopsis seedlings to moderate heat stress, shedding light on the delicate balance between proteome stability and adaptability. These findings significantly contribute to our understanding of plant thermal resilience and offer valuable support for the development of crops endowed with enhanced thermotolerance.