The present study investigates the barley cDNA clones paf93 and cdr29
which correspond to mRNAs regulated by low temperature and drought str
ess but not by exogenous ABA treatment. During the early stage of dehy
dration, these mRNAs are expressed before the induction of known ABA r
egulated genes such as dehydrins and when only a small increase occurs
in ABA content, The cDNA clone cdr29 cross-hybridizes with two classe
s of mRNAs differing both in size and expression patterns, The sequenc
e analysis revealed that paf93 encodes a protein homologous with the c
old-regulated protein COR47 of Arabidopsis whereas cdr29 represents a
plant gene homologous to yeast and mammalian sequences coding for acyl
-coenzyme A oxidase.