Calcium Signalling in Plant Biotic Interactions

Abstract

Calcium (Ca2+) is a universal second messenger involved in various cellular processes, leading to plant development and to biotic and abiotic stress responses. Intracellular variation in free Ca2+ concentration is among the earliest events following the plant perception of environmental change. These Ca2+ variations differ in their spatio-temporal properties according to the nature, strength and duration of the stimulus. However, their conversion into biological responses requires Ca2+ sensors for decoding and relaying. The occurrence in plants of calmodulin (CaM) but also of other sets of plant-specific Ca2+ sensors such as calmodulin-like proteins (CMLs), Ca2+-dependent protein kinases (CDPKs) and calcineurin B-like proteins (CBLs) indicate that plants possess specific tools and machineries to convert Ca2+ signals into appropriate responses. Here, we focus on recent progress made in monitoring the generation of Ca2+ signals at the whole plant or cell level and their long distance propagation during biotic interactions. The contribution of CaM/CMLs and CDPKs in plant immune responses mounted against bacteria, fungi, viruses and insects are also presented.

Genotypic Variation in Resistance Gene-Mediated Calcium Signaling and Hormonal Signaling Involved in Effector-Triggered Immunity or Disease Susceptibility in the Xanthomonas campestris pv. Campestris–Brassica napus Pathosystem

“…Mosa with Xcc inoculation ( Figure 3A). Another calcium signaling gene, CDPK5, is an important calcium sensor [6,7,25] in biotic stress that is also induced in cv. Mosa ( Figure 3B) after Xcc inoculation.…”

CRb and PbBa8.1 Synergically Increases Resistant Genes Expression upon Infection of Plasmodiophora brassicae in Brassica napus

“…Calcium is considered to be an imperative secondary messenger in the signal transduction pathway, which plays a vital role in plants in the production of HR in response to biotic stress [31,32]. In this study, the down-regulation of CMLs, CIPKs, and CDPKs was highly suppressed in 618R as compared to 305R and 409R.…”

Hydrogenases and the Role of Molecular Hydrogen in Plants

“…Again, no similarly to this sequence is found in either the HYDA1 and HYDA2 amino acid sequences, which is not surprising as Prosite [ 42 ] does not predict the presence of a EF-hand consensus sequence either. This latter point might cast doubt on any control through Ca 2+ metabolism too, which is important in many plant cell responses [ 44 ], although there are other methods of Ca 2+ ion control other than the action of EF-hands.…”