ABSTRACT--Abstract: Kernel texture (“hardness”) is an important trait that determines end-use quality of wheat (Triticum aestivum and T. turgidum spp. durum).
Variation in texture is associated with the presence/absence or
sequence polymorphism of two proteins, puroindoline a and puroindoline
b. This work describes the flanking and coding region sequences of
puroindoline a and puroindoline b from 25 accessions representing wild
diploid taxa of the Triticeae related to the three genomes of T. aestivum. The puroindoline sequences from the diploid taxa were compared to those from hard and soft T. aestivum
wheat cultivars. Nucleotide sequence comparisons and database
searches facilitated the identification of the 5’ proximal regulating
regions, revealing the presence of several putative control
elements. An absolute conservation of some known regulatory
elements for tissue specificity was observed, while different rates of
conservation of reiterated motifs with possible enhancer functions, and
the exclusive presence of some elements either in puroindoline a or
puroindoline b were also found. The main features of both proteins were
all conserved, with special regard to the signal peptide, the N- and
C-terminal cleavable peptides, the cysteine backbone and the
tryptophan-rich domain. The hydrophobicity and basic identity of
the proteins were generally preserved.