The 30th International Conference on Arabidopsis Research (ICAR 2019)

560 / 2019-03-16 15:36:49

Regulatory role of autophagy during thermomemory in Arabidopsis

arabidopsis, autophagy, thermomemory, proteomics

Plenary track > Abiotic Stress

Experimental evidence shows plants have a memory for heat stress (thermomemory). Pre-exposure of plants to high, but non-lethal temperature enables them to perform efficiently upon future, severe heat stress (HS) through attaining short-term memory. However, molecular mechanisms of short-term memory state remains largely unexplored. Recently, our lab identified a novel role of autophagy for the regulation of thermomemory in Arabidopsis thaliana. Autophagy is an evolutionarily conserved and dynamic recycling process critical for maintaining cellular energy homeostasis. While it has been considered that autophagy is a bulk degradation process, recent advances provide evidence that autophagy can be highly specific. Here, by proteomics, we identified REST1 (RESETTER1), a receptor for selective autophagy, as a regulator of thermomemory in Arabidopsis. Mutants lacking REST1 revealed a better thermomemory. Immunoblot analysis showed higher accumulation of REST1 protein during the thermomemory phase in autophagy-deficient mutants than in Col-0. Using confocal microscopy, we demonstrated an accumulation and higher activity of REST1 bodies during the thermomemory phase. Furthermore, we show an involvement of autophagy in the degradation of REST1. We identified novel substrates of REST1 during thermomemory, by conducting and comparing proteomic datasets of REST1. We validated the involvement of REST1 in degrading its cargo proteins during memory phase. Recent data will be shown.