Reference "Developmentally regulated plant genes: the nucleotide sequence of a wheat gliadin genomic clone"

Reference ID

9105

Title

Developmentally regulated plant genes: the nucleotide sequence of a wheat gliadin genomic clone

Source

The EMBO journal, 1984, vol. 3, pp. 1409-1415

Authors (6)

Rafalski-J-A	Scheets-K
Metzler-M	Peterson-D-M
Hedgcoth-C	Soll-D-G

Abstract

Gliadins, the major wheat seed storage proteins, are encoded by a multigene
family. Northern blot analysis shows that gliadin genes are transcribed in
endosperm tissue into two classes of poly(A)+ mRNA, 1400 bases (class I) and
1600 bases (class II) in length. Using poly(A)+ RNA from developing wheat
endosperm we constructed a cDNA library from which a number of clones coding for
alpha/beta and gamma gliadins were identified by hybrid-selected mRNA
translation and DNA sequencing. These cDNA clones were used as probes for the
isolation of genomic gliadin clones from a wheat genomic library. One such
genomic clone was characterized in detail and its DNA sequence determined. It
contains a gene for a 33-kd alpha/beta gliadin protein (a 20 amino acid signal
peptide and a 266 amino acid mature protein) which is very rich in glutamine
(33.8%) and proline (15.4%). The gene sequence does not contain introns. A
typical eukaryotic promoter sequence is present at -104 (relative to the
translation initiation codon) and there are two normal polyadenylation signals
77 and 134 bases downstream from the translation termination codon. The coding
sequence contains some internal sequence repetition, and is highly homologous to
several alpha/beta gliadin cDNA clones. Homology to a gamma-gliadin cDNA clone
is low, and there is no homology with known glutenin or zein cDNA sequences.