Involved dehydration tolerance. Involved in the adaptive response of vascular plants to withstand water deficit (PubMed:20668063). May possess chaperone-like activity under water deficit (PubMed:27006402). Binds to negatively charged membranes of liposomes. This binding induces partial folding of the largely unstructured LEA18 protein, vesicle aggregation, and leakage of soluble content from liposomes (PubMed:20875393). Expressed during embryo development and in dry seed. Expression decreases significantly after seed germination. By dehydration stress. Under water deficit, the N-terminal region is necessary and sufficient for conformational transition from disordered to alpha-helix folding. This conformational transition is required for chaperone-like activity under water limitation. Belongs to the LEA type 1 family.