Involved in resistance to abiotic stress. Heterodimers (PubMed:29272523). Interacts with CYSTM7 and WIH1/CYSTM13 (PubMed:29272523). Mostly expressed in roots, stems, rosette leaves and siliques and, to a lower extent, in flowers and cauline leaves. Induced by heat in roots, but suppressed in shoots (PubMed:29272523). Accumulates in response to cold, drought, oxidation stress and salt (PubMed:29272523). Belongs to the CYSTM1 family. Extended C-terminus.