Stress responses mediated by the CBL calcium sensors in plants

Abstract

Calcium ions (Ca²⁺) are involved as second messenger in plant responses to a broad array of environmental stimuli, including biotic and abiotic stresses. Therefore, understanding Ca²⁺-signaling mechanisms may lead to the development of transgenic crops with enhanced tolerance to adverse environmental conditions. In order to initiate the signaling cascades and give rise to relevant cellular and physiological responses, changes in the parameters of Ca²⁺ transients should be first detected by appropriate Ca²⁺ sensors in plant cells. In this regard, elucidations of plant Ca²⁺ sensors and their target molecules are critical steps for unraveling the Ca²⁺ signal transduction pathways. Recent studies have revealed that plants possess many Ca²⁺-binding proteins with different properties, which can serve as distinct Ca²⁺ sensors. This present review mainly focuses on a family of calcineurin B-like Ca²⁺ sensors which has been most recently identified from higher plants including Arabidopsis, rice, maize and pea.