MCU proteins dominate in vivo mitochondrial Ca2+ uptake in Arabidopsis roots

• DOI: 10.1093/plcell/koac242
• Publication Date: 2022-08-08T11:28:17Z
• Authors: Cristina Ruberti; Elias Feitosa-Araujo; Zhaolong Xu; Stephan Wagner; Matteo Grenzi; Essam Darwish; Sophie Lichtenauer; Philippe Fuchs; Ambra Selene Parm...; Daria Balcerowicz; Sébastjen Schoenaers; Carolina de la Torre; Khansa Mekkaoui; Adriano Nunes-Nesi; Markus Wirtz; Kris Vissenberg; Olivier Van Aken; Bettina Hause; Alex Costa; Markus Schwarzländer
• Keywords: CALCIUM UNIPORTER; MICE LACKING; CYTOSOLIC CA2+; RETROGRADE REGULATION; STRESS RESPONSES; OSMOTIC-STRESS; LONG-DISTANCE; ION CHANNELS; CELL-DEATH; JASMONATE; Mammals; 0301 basic medicine; Calcium-Binding Proteins; Arabidopsis; Mitochondria; [SDV] Life Sciences [q-bio]; Mitochondrial Proteins; Chemistry; 03 medical and health sciences; Animals; Calcium; Human medicine; Calcium Channels; Biology; Research Articles

Ca2+ signaling is central to plant development and acclimation. While Ca2+-responsive proteins have been investigated intensely in plants, only a few Ca2+-permeable channels identified, our understanding of how intracellular fluxes facilitated remains limited. Arabidopsis thaliana homologs the mammalian channel-forming mitochondrial calcium uniporter (MCU) protein showed transport activity vitro. Yet, evolutionary complexity MCU proteins, as well reports about alternative systems unperturbed uptake knockout lines genes, leave critical questions vivo functions family plants unanswered. Here, we demonstrate that mediate planta this mechanism major route for fast uptake. Guided by subcellular localization, expression, conservation generated an mcu triple line. Using imaging living root tips stimulation transients different amplitudes, demonstrated became limiting mutant. The drastic cell physiological phenotype impaired coincided with deregulated jasmonic acid-related thigmomorphogenesis. Our findings establish MCUs entry link phytohormone signaling.