Abstract
Bisabolene-type sesquiterpenoids, which have multiple bioactivities, including anticancer activity, are one of the main groups of compounds in the essential oil extracted from Santalum album L. and other Santalum species. Bisabolene synthetase (SaBS) is a key enzyme for the synthesis of bisabolene in S. album, but the regulation of the SaBS gene’s expression is poorly understood. In this study, a 1390-bp promoter sequence of the SaBS gene was isolated from the leaves of six-year-old S. album. A bioinformatics analysis showed that certain environment stresses and phytohormone-activated cis-acting elements were distributed in different regions of the SaBS promoter (PSaBS). Transgenic Arabidopsis carrying full-length PSaBS had significantly higher β-glucuronidase (GUS) activity than the untreated control after treatment with salicylic acid (SA), suggesting that PSaBS is a SA-inducible promoter. Histochemical GUS staining and GUS fluorometric assays of transgenic Arabidopsis showed that the GUS activity directed by PSaBS was mainly expressed in stem tissue, followed by leaves and flowers. Moreover, different regions of PSaBS showed significantly different GUS activity. A 171-bp fragment upstream of the transcriptional initiation codon (ATG) is the core promoter region of PSaBS. Our results provide insight into and a greater understanding of the transcriptional regulation mechanism of the SaBS gene, which could serve as an alternative inducible promoter for transgenic plant breeding.
Highlights
Terpenes are the largest group of plant secondary metabolites with diversified structures and functions
Tail-PCR was used to isolate the species. Bisabolene synthetase (SaBS) promoter by gene-specific primers, as well as random primers (Table 1) with genomic DNA extracted from S. album leaves as the template
Bioinformatics analysis showed that PSaBS consists of abundant TATA and CAAT boxes, containing
Summary
Terpenes are the largest group of plant secondary metabolites with diversified structures and functions. Bisabolenes are a type of sesquiterpenoid with diverse bioactivities, including an anticonvulsant effect [1], inhibition of. Many bisabolene-type sesquiterpenoids have been isolated and identified in various plants, such as β-bisabolenol and β-bisabolenal in Neocallitropsis pancheri [5], artaboterpenoids A and B in Artabotrys hexapetalus [6], and halichonic acid from a marine sponge Halichondria sp. The gene encoding bisabolene synthetase is SaBS. It is a terpene synthase that can catalyze the rate-limiting step of converting farnesyl diphosphate into bisabolene in S. album [10]. The regulation of SaBS gene expression has not been defined
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
