Calcium signaling is involved in diverse cellular processes in fungi

Calcium (Ca(2+)) is a universal signalling molecule of life. The Ca(2+) signalling is an evolutionarily conserved process from prokaryotes to eukaryotes. Ca(2+) at high concentration is deleterious to the cell; therefore, cell maintains a low resting level of intracellular free Ca(2+) concentration ([Ca(2+)](c)). The resting [Ca(2+)](c) is tightly regulated, and a transient increase of the [Ca(2+)](c) initiates a signalling cascade in the cell. Ca(2+) signalling plays an essential role in various processes, including growth, development, reproduction, tolerance to stress conditions, and virulence in fungi. In this review, we describe the evolutionary aspects of Ca(2+) signalling and cell functions of major Ca(2+) signalling proteins in different fungi.