Cloning and characterization of squalene synthase and cycloartenol synthase from.
10.1016/j.apsb.2016.06.012
- Author:
Huan ZHAO
1
;
Qi TANG
2
;
Changming MO
3
;
Longhua BAI
3
;
Dongping TU
1
;
Xiaojun MA
1
Author Information
1. The Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100194, China.
2. Hunan Provincial Key laboratory of Crop Germplasm Innovation and Utilization and National Chinese Medicinal Herbs (Hunan) Technology Center, Hunan Agricultural University, Changsha 410128, China.
3. Guangxi Botanical Garden of Medicinal Plant, Nanning 530023, China.
- Publication Type:Journal Article
- Keywords:
Cloning;
Cycloartenol synthase;
Expression;
Siraitia grosvenorii;
Squalene synthase;
Steroids;
Subcellular localization;
Triterpenoids
- From:
Acta Pharmaceutica Sinica B
2017;7(2):215-222
- CountryChina
- Language:English
-
Abstract:
Mogrosides and steroid saponins are tetracyclic triterpenoids found in. Squalene synthase (SQS) and cycloartenol synthase (CAS) are key enzymes in triterpenoid and steroid biosynthesis. In this study, full-length cDNAs ofandwere cloned by a rapid amplification of cDNA-ends with polymerase chain reaction (RACE-PCR) approach. ThecDNA has a 1254 bp open reading frame (ORF) encoding 417 amino acids, and thecDNA contains a 2298 bp ORF encoding 765 amino acids. Bioinformatic analysis showed that the deduced SgSQS protein has two transmembrane regions in the C-terminal. Bothandhave significantly higher levels in fruits than in other tissues, suggesting that steroids and mogrosides are competitors for the same precursors in fruits. Combinedprediction and subcellular localization, experiments in tobacco indicated that SgSQS was probably in the cytoplasm or on the cytoskeleton, and SgCAS was likely located in the nucleus or cytosol. These results will provide a foundation for further study ofandgene functions in, and may facilitate improvements in mogroside content in fruit by regulating gene expression.
