Chaperone that binds to RNA, single- (ssDNA) and double-stranded (dsDNA) DNA, and unwinds nucleic acid duplex. Exhibits a DNA melting activity. May be involved in cold resistance. Prevents seed germination under dehydration or salt stress conditions. Mostly expressed in shoot apices and siliques, and, to a lower extent, in roots, cotyledons, stems, shoots, leaves, floral buds and flowers. High expression in the earliest stage of silique development, with a decrease during the middle stages of silique development and subsequently an increase during the later stages. Accumulates during cold acclimation, but down-regulated by dehydration and salt stresses. Belongs to the cold shock protein (CSP) family.