Isolation and characterization of a differentially expressed sequence tag from Triticum darum salt-stressed roots

Stress responses in plants are important for environmental adaptation and a re associated with rapid changes in gene expression. In order to investigat e correlations between phenotypic adaptation to stress limitation and induc ed gene expression, we have studied a model system consisting of a salt-tol erant line (R1) and a salt-sensitive line (S1) of durum wheat (Triticum dur ian Desf.) subjected to a severe short-term NaCl treatment (200 mM). A mRNA differential display was established for this system to allow the identifi cation of cDNAs induced during salt stress. We cloned and sequenced a cDNA fragment corresponding to a gene that was differentially expressed in salt- stressed (R1) wheat seedlings. Based on the high similarity between the pre dicted translation product of the cDNA sequence and known members of the de hydrin protein family from wheat (group 2 LEA protein), the cDNA was identi fied as a member of this gene family. The gene was strongly and rapidly ind uced in roots and leaves of R1 plants but induction was delayed and transcr ipts accumulated to a low level in S1 plants. (C) 2001 Editions scientifiqu es et medicales Elsevier SAS.