A cDNA clone of maize Adh1 which contains the entire protein coding region of the gene has been constructed. The protein sequence predicted from the nucleotide sequence is in agreement with limited protein sequencing data for the ADH1 enzyme. An 11.5 kb genomic fragment containing the Adh1 gene has been isolated using the cDNA clone as a probe, and the gene region fully sequenced. The gene is interrupted by 9 introns, their junction sequences fitting the animal gene consensus sequence. Within the gene there is a triplication of a segment (104 bp) spanning an intron-exon junction. Presumptive promoter elements have been identified and are similar in nucleotide sequence and location, relative to the start of transcription, to those of other plant and animal genes. No recognizable poly(A+) addition signal is evident. Comparison of the nucleotide sequences of the cDNA (derived from an Adh1 -F allele) and genomic (derived from an Adh1 -S allele) clones has identified an amino acid difference consistent with the observed difference in electrophoretic mobility of the two enzymes. The maize ADH1 amino acid sequence is 50% homologous to that of horse liver ADH but is only 20% homologous to yeast ADH.

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Two cDNA clones were characterized which correspond to different RNA species whose level is increased by gibberellic acid (GA3) in barley (Hordeum vulgare L.) aleurone layers. On the criteria of amino terminal sequencing, amino acid composition and DNA sequencing it is likely that one of these clones (pHV19) corresponds to the mRNA for α-amylase (1,4-α-D-glucan glucanohydrolase, EC 3.2.1.1.), in particular for the B family of α-amylase isozymes (Jacobsen JV, Higgins TJV: Plant Physiol 70:1647-1653, 1982). Sequence analysis of PHV19 revealed a probable 23 amino acid signal peptide. Southern hybridization of this clone to barley DNA digested with restriction endonucleases indicated approximately eight gene-equivalents per haploid genome.The identity of the other clone (pHV14) is unknown, but from hybridization studies and sequence analysis it is apparently unrelated to the α-amylase clone.Both clones hybridize to RNAs that are similar in size (∼1500b), but which accumulate to different extents following GA3 treatment: α-amylase mRNA increases approximately 50-fold in abundance over control levels, whereas the RNA hybridizing to pHV14 increases approximately 10-fold. In the presence of abscisic acid (ABA) the response to GA3 is largely, but not entirely, abolished. These results suggest that GA3 and ABA regulate synthesis of α-amylase in barley aleurone layers primarily through the accumulation of α-amylase mRNA.