| Avenin-like b was found recently in reseach on wheat storage proteins. It was expressed specificly in endosperm of wheat seed and was defined as"wheat low molecular weight gliadins", which were rich in cysteine. Disulfide bond can be formed between those cysteine residues and these proteins could probably aggregate into polymer,therefore, they may play an important part in wheat processing quality. Previously, several avenin-like b genes have been isolated and characterized in our laboratory. In the present research, a DNA fragment flanking 5, end of avenin-like b gene has been isolated. Five avenin-like b gene promoter-driven gus gene expression vectors with different deletions of avenin-like b gene promoter were constructed.The main results are as follows1) Based on the DNA sequence of avenin-like b gene, a 1664 bp promoter sequence upstream the translation start site was isolated by Inverse-PCR technique.2) Putative fuctional promoter elements were analyzed by the PLACE datebase and the PlantCARE datebase. The results showed that the promoter sequence included the basic elements for example CAAT-box and TATA-box. The promoter also has some endosperm-specific elements such as GCN4,TGTAAAG,Skn1-motif and AACA indicating that these motifs may confer endosperm-specific expression for the promoter driven gene.3) To analyze and identify the expression specificity and expression intensity of avenin-like b gene promoter, one vector named pALP17 containing 1664 bp promoter sequence and four other vector respectively named pALP3/6/8/10 containing different 5,length of the full promoter were succsessfully constructed.Isolation and fuctional analysis of wheat endosperm-specific promoters can contribute to study the mechanism of seed development and the regulation mechanism of endosperm-specific genes. Endosperm-specific promoters can be used to gene modification in plant genetic engineering. Thus, it has potential applications both in theorey and practical applications. |
PDF Full Text Request