Chaperone that binds to and unwinds RNA and both single-stranded DNA and double-stranded DNA (ssDNA and dsDNA DNA) (By similarity). Regulates the flowering transition and flower and seed development, particularly at late stages of embryo development, through regulation of gene expression (including MEA, FIS2, AP1, CAL, AG and SHP2). Mostly expressed in shoot apices and siliques, and, to a lower extent, in roots, cotyledons, stems, shoots, leaves, floral buds and flowers. Present in shoot apical meristems and siliques (at protein level). Very low levels are observed in cv. Landsberg erecta compared to cv. Columbia (PubMed:19269998). Accumulates in floral buds, flowers, developing embryos during an early stage of silique development. Down-regulated during cold acclimation. Accumulation during silique development is AGL15-dependent. Belongs to the cold shock protein (CSP) family.