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Ammopiptanthus mongolicus is the only evergreen broadleaf shrub endemic to the Alashan Desert in northwestern China. The plants can survive temperatures of -30 A degrees C or less in winter. A dehydrin-like protein gene, AmCIP, cloned from a cold-acclimated A. mongolicus seedling was transformed into E. coli. The transgenic strains exhibited enhanced freezing tolerance compared with non-transformed host cells. The recombinant AmCIP remained soluble pre- and post-boiling for 10 min, and protected activity of lactate dehydrogenase during two freeze-thaw cycles more effectively than bovine serum albumin, a protein with a proven cryoprotective effect. Expression of AmCIP in transgenic tobacco increased cold tolerance during seed germination and seedling growth. The YFP-AmCIP fusion protein was localized in the cytoplasm and nucleus in onion inner epidermal cells, indicating that AmCIP might function both in the cytoplasm and nucleus.