Abstract: DREB ( dehydration responsive element-binding factor) genes encode a small family of transcriptional activators functioning in plant tolerance and acclimation to various stresses. To investigate the molecularmechanisms underlying stress resistance in aloe (Aloe vera L. var. chinensis) , a new gene encoding DREB protein was cloned from aloe via combined method of PCR and 3′RACE. Based on the high homology to previous reported AlDREB1 , this gene (GenBank accession number, FJ560460) was named as AlDREB2 .
Sequence alignment analysis located AlDREB2 to A26 sub-group of DREB family. RT-PCR revealed that expression of AlDREB2 was significantly induced by ABA and dehydration treatments ( salt or PEG6000 ) , though with different dynamic patterns. Besides, transcript accumulation of AlDREB2 was up-regulated by cold stress and external ethylene. These results best support the interp retation that AlDREB2 is an active regulator involved in dehydration tolerance and cold acclimation in aloe.

Key words: Aloe vera L. var. chinensis (Haw. ) Berger, AlDREB2, DREB transcrip tion factor, stress treatment