Is there crosstalk between extracellular and intracellular calcium mobilization in jasmonic acid signaling

Abstract

The changes in cytosolic Ca2+ levels play an important role in the jasmonic acid (JA) signal transduction pathway. We demonstrate that an increase in cytosolic free Ca2+ concentration ([Ca2+]cyt) of Arabidopsis leaf cells was affected by pretreatment with heparin and 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl ester (TMB-8). With pretreatment of heparin, an antagonist of inositol 1,4,5-trisphosphate (IP3) sensitive channels, the basal and JA induced fluorescence of [Ca2+]cyt were both decreased. Furthermore, heparin and TMB-8, another antagonist of IP3 sensitive channels, enhanced the JA-induced gene expression of JR1. These data suggest that there may be a fine tune control system between extracellular and intracellular Ca2+ mobilization in JA signaling pathway.