|
|
|
| Cloning and Characterization of Sucrose Synthase （Susy2）Gene in Sweet Sorghum（Sorghum bicolor (L.) Moench） |
| 1, 1, |
|
|
|
|
Abstract Abstract：Sweet Sorghum (Sorghum bicolor (L.)Moench) accumulates large amount of sugars in the culm parenchyma. Culm extracts can be used for manufacture of sucrose and syrup. Furthermore, sweet sorghum has been identified as a good biomass crop for fermentation to ethanol. Sucrose Synthase (SuSy) plays an important role in plant growth and development. It can regulate sucrose contents in storage tissue of many plants. In this paper, a novel full-length sweet sorghum sucrose synthase gene (Susy2, GenBank Accession, FJ513325) DNA sequence was cloned by blasting the sorghum bicolor EST database with the sugarcane Susy2 (GenBank Accession, AY118266) cDNA sequence information as a querying probe. It was also verified by genome-PCR. The full-length DNA of 4587bp contains fifteen exons that were separated by fourteen introns and a 2409 bp open reading frame (ORF). Protein encoded by Susy2, molecular weight of 91.7 kD, is comprised of 802 amino acids. Its isoelectric point (pI) is 6.15. Conserved domain searching results showed that this protein contains a GT1 family of glycosyl transferases which have four ADP-binding pockets and catalyzes the synthesis of sucrose 6-phosphate from fructose 6-phosphate and uridine 5'-diphosphate-glucosewas. SuSy is very conservative among sorghum, sugarcane, maize, rice, bamboo, wheat and ryegrass. The results will provide a help for improving of characters by biotechnology and researching of molecular mechanism of sucrose accumulation in sweet sorghum.
Key words： sweet sorghum；sucrose synthase；clone；PCR；EST database
|
|
Received: 20 February 2009
|
|
|
|
|
|
|
