The Arabidopsis Synaptotagmin1 Is Enriched in Endoplasmic Reticulum-Plasma Membrane Contact Sites and Confers Cellular Resistance to Mechanical Stresses. Issue 1 (19th March 2015)

• Record Type: Journal Article
• Authors: Pérez-Sancho, Jessica; Vanneste, Steffen; Lee, Eunkyoung; McFarlane, Heather E.; Esteban del Valle, Alicia; Valpuesta, Victoriano; Friml, Jiří; Botella, Miguel A.; Rosado, Abel
• Is Part Of: Plant physiology. Volume 168:Issue 1(2015)
• Page Start: 132
• Page End: 143
• Publication Date: 2015-03-19
• Subjects: Plant physiology -- Periodicals; Botany -- Periodicals; Periodicals; Electronic journals; 571.2
• DOI: 10.1104/pp.15.00260
• Languages: English
• ISSNs: 0032-0889

Abstract

Abstract : A phospholipid binding protein is enriched on specific organelle contact sites and maintains the mechanical stability of plant cells upon stress exposure. Abstract: Eukaryotic endoplasmic reticulum (ER )-plasma membrane (PM ) contact sites are evolutionarily conserved microdomains that have important roles in specialized metabolic functions such as ER -PM communication, lipid homeostasis, and Ca 2+ influx. Despite recent advances in knowledge about ER -PM contact site components and functions in yeast ( Saccharomyces cerevisiae ) and mammals, relatively little is known about the functional significance of these structures in plants. In this report, we characterize the Arabidopsis ( Arabidopsis thaliana ) phospholipid binding Synaptotagmin1 (SYT1) as a plant ortholog of the mammal extended synaptotagmins and yeast tricalbins families of ER -PM anchors. We propose that SYT1 functions at ER -PM contact sites because it displays a dual ER -PM localization, it is enriched in microtubule-depleted regions at the cell cortex, and it colocalizes with Vesicle-Associated Protein27-1, a known ER -PM marker. Furthermore, biochemical and physiological analyses indicate that SYT1 might function as an electrostatic phospholipid anchor conferring mechanical stability in plant cells. Together, the subcellular localization and functional characterization of SYT1 highlights a putative role of plant ER -PM contact site components in the cellular adaptation to environmental stresses.