PsCor413pm2, a Plasma Membrane-Localized, Cold-Regulated Protein from Phlox subulata, Confers Low Temperature Tolerance in Arabidopsis

Abstract

Low temperature stress adversely affects plant growth and development. Isolation and characterization of cold response genes from cold-tolerant plants help to understand the mechanism underlying low temperature tolerance. In this study, <i>PsCor413pm2</i>, a cold-regulated (COR) gene isolated from <i>Phlox subulata</i>, was transferred to <i>Arabidopsis</i> plants to investigate its function. Real-time quantitative PCR analysis revealed that <i>PsCor413pm2</i> expression was induced by cold. Subcellular localization revealed that the PsCor413pm2-green fluorescent protein (GFP) fusion protein localized to the plasma membrane in tobacco and <i>Arabidopsis</i> plants. Furthermore, overexpression of <i>PsCor413pm2</i> in <i>Arabidopsis</i> plants enhanced tolerance to low temperature stress. Transgenic <i>Arabidopsis</i> roots had more influx of Ca²⁺ after a cold shock than wild-type plants, as shown using non-invasive micro-test technology (NMT). Moreover, the transcription abundance of five <i>COR</i> and two C-repeat (CRT) binding factor (CBF) genes in transgenic <i>Arabidopsis</i> plants was higher than that in the wild-type plants under cold stress. Taken together, our results suggest that overexpression of <i>PsCor413pm2</i> enhances low temperature tolerance in <i>Arabidopsis</i> plants by affecting Ca²⁺ flux and the expression of stress-related <i>COR</i> and <i>CBF</i> genes.