InterPro domain: IPR044750

This is the C2 domain found in plant proteins, including SRC2 (Soybean genes Regulated by Cold 2) and BAP1/2 (BON1-associated protein 1/2), which are involved in defence responses [ 1 , 2 ]. SRC2 is induced after pathogen infiltration and in cold conditions. Arabidopsis SRC2 homologue functions as a calcium-dependent activator of the NADPH oxidase AtRbohF, that mediates reactive oxygen species (ROS) production after cold induction. SRC2 contains a single C2 domain which localizes to the plasma membrane and is involved in Ca2+ dependent protein binding [ 3 ]. BAP1/2 are negative regulators of cell death and defense responses, as they repress the activity of disease resistance (R) genes [ 3 ].

1. A low temperature-inducible protein AtSRC2 enhances the ROS-producing activity of NADPH oxidase AtRbohF. Biochim Biophys Acta 1833, 2775-2780
2. The Arabidopsis BAP1 and BAP2 genes are general inhibitors of programmed cell death. Plant Physiol 145, 135-46
3. The C2 domain protein BAP1 negatively regulates defense responses in Arabidopsis. Plant J 48, 238-48