Abstract
The amylose-extender (Ae) gene encoding starch-branching enzyme IIb (SBEIIb) in maize is predominantly expressed in endosperm and embryos during kernel development. A maize genomic DNA fragment (-2964 to +20485) containing the Ae gene was isolated and sequenced. The maize Ae mRNA is derived from 22 exons distributed over 16914 bp. Twenty-one introns, differing in length from 76 bp to 4020 bp, all have conserved junction sequences (GT··AG). Sequence analysis of the 5'- and 3'-flanking regions revealed a consensus TATA-box sequence located 28 bp upstream of the transcription initiation site as determined by primer extension analysis, and a putative polyadenylation signal observed 29 bp upstream of the polyadenylation site based on cDNA sequence. Genomic Southern blot analysis suggests that a single Ae gene is present in the maize genome. Promoter activity was confirmed by testing a transcriptional fusion of the Ae 5'-flanking region between -2964 and + 100 to a luciferase reporter gene in a transient expression assay using maize endosperm suspension cultured cells. 5' deletion analysis revealed that the 111 bp region from -160 to -50 is essential for high-level promoter activity.
Original language | English (US) |
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Pages (from-to) | 945-956 |
Number of pages | 12 |
Journal | Plant molecular biology |
Volume | 38 |
Issue number | 6 |
DOIs | |
State | Published - Dec 1998 |
All Science Journal Classification (ASJC) codes
- Agronomy and Crop Science
- Genetics
- Plant Science