Calmodulin-related proteins step out from the shadow of their namesake

Abstract

Emerging roles for these proteins in plant development and stress response highlight their importance in plant signaling, and their functional diversity underscores the significance of Ca²⁺ as a second messenger in plants.

Figure 1.

Working model of CML function in plant cells. This model displays known and hypothetical roles (red dashed boxes) for CMLs in development and stress response. CMLs are distributed among various cellular compartments and in at least one case, relocate in response to stimuli (CML19, dashed arrow). The model draws primarily from studies using Arabidopsis, but a role for rgsCaM from tobacco is also presented. Physiological responses mediated by CMLs are displayed as yellow boxes. For many CMLs, their downstream targets (blue boxes) are unknown or it is unclear whether putative targets are involved in CML-mediated pathways (denoted by a question mark). The suggested physiological functions of the CMLs depicted are described in the text. Black and blunted arrows indicate positive or negative regulation, respectively.