Search

Wheat Avenin-like proteins (TaALP) are atypical storage proteins belonging to the Prolamin superfamily. Previous studies on ALPs have focused on the proteins’ positive effects on dough strength, whilst no correlation has been made between TaALPs and the plant immune system. Here, we performed genome-wide characterization of ALP encoding genes in bread wheat. In silico analyses indicated the presence of critical peptides in TaALPs that are active in the plant immune system. Pathogenesis-related nucleotide motifs were also identified in the putative promoter regions of TaALP encoding genes. RT-PCR was performed onTaALPand previously characterised pathogenesis resistance genes in developing wheat caryopses under control andFusarium graminearuminfection conditions. The results showed thatTaALPand NMT genes were upregulated uponF. graminearuminoculation. mRNA insitu hybridization showed thatTaALPgenes were expressed in the embryo, aleurone and sub-aleurone layer cells. SevenTaALPgenes were cloned for the expression of recombinant proteins inEscherichia coli, which displayed significant inhibitory function onF. graminearumunder anti-fungal tests. In addition, FHB index association analyses showed that allelic variations of two ALP genes on chromosome 7A were significantly correlated with FHB symptoms. Over-expression of an ALP gene on chromosome 7A showed an enhanced resistance to FHB. Yeast two Hybridization results revealed that ALPs have potential proteases inhibiting effect on metacaspases and beta-glucosidases. A vital infection process related pathogen protein,F. graminearumBeta-glucosidase was found to interact with ALPs. Our study is the first to report a class of wheat storage protein or gluten protein with biochemical functions. Due to its abundance in the grain and the important multi-functions, the results obtained in the current study are expected to have a significant impact on wheat research and industry.