Evaluation and characterization of an endosperm-specific sbeⅡa promoter in wheat

作者：MIAO Hongmei; Fleming Joy E; U Debing; HAN Jinfeng

来源：科学通报(英文版), 2004, 49(6): 579-585.

DOI：10.1360/03wc0505

• starch branching enzyme
• promoter analysis
• endosperm-specific
• transient assay
• Triticum aestivum L

Starch, the main component of the wheat grain,is the product of a complex biochemical pathway. The sbeⅡa gene plays a key role in controlling the synthesis of starch, in particular, the biosynthesis of amylopectin, in maturing wheat grain. To investigate its regulatory mechanisms and endosperm-specific expression pattern, the sbeⅡa promoter (3094 bp in length) was cloned using APCR and sequenced.The effect of a series of deletions was studied using a GUS transient assay system. Results showed that the 3094 bp sequence (sbe.g construct) exhibited full stable promoting activity and that the activities of 5′ or 3′ deletions reduced levels of GUS expression. Some constructs with internal deletions showed only weak activity, however, sbe.e, with a deletion from -1579-1210 bp resulted in higher levels of expression than the full-length promoter sequence, sbe.g. This indicates that motifs such as the -300 bp element, G-box and/or P-box act as positive elements and are necessary in determining the promoter's endosperm-specific pattern and that negative repressor elements or motifs may also be present within the -1579-1210 bp sequence. The age of wheat endosperm tissue used in the GUS-transient assay system is shown to be of significant importance.

• 出版日期2004