Functional characterization of the Ginkgo biloba chalcone synthase gene promoter in transgenic tobacco

Abstract

ABSTRACT. The regulative sequence (2273 bp) of the chalcone synthase gene promoter of biloba was cloned by genomic walking. A 2273-bp promoter 5' upstream translation start site of GbCHS was cloned and designated as GbCHSP. pBI121+CHSP:GUS and pBI121-35S:GUS were constructed and transformed into tobacco by LBA4404. We found that GbCHSP could drive transient expression of GUS in tobacco and differentially expressed in root, stem and leaf tissues of this plant. GUS activity regulated by the CHSP promoter were located in tissues (apical meristems) at the growing points of roots and stems. pBI121+CHSP:GUS could be induced by wounding, copper, UV-B, abscisic acid, and ethephon treatments of transgenic seedlings. This activity was weakly Ginkgo biloba chalcone synthase gene promoter in tobacco inhibited by gibberellin. Deletion analysis of the CHSP promoter in transgenic tobacco showed that CHSP1 complete promoter conferred a GUS expression and activity similar to that of 35 S(CaMV). GUS activity dropped dramatically when there were CHSP4, CHSP5 constructs and was almost totally absent when the CHSP6 construct was present. We conclude that the upstream sequence -1548 to -306 of GbCHSP is the main region for transcriptional regulation of the CHS gene and that it is activated by hormone and stress factors in G. biloba. These results will help us to understand the transcriptional regulatory mechanisms involved in GbCHS expression and flavonoid accumulation in G. biloba.

Chalcone synthase (CHS) family members analysis from eggplant (Solanum melongena L.) in the flavonoid biosynthetic pathway and expression patterns in response to heat stress

“…It is well known that CHS is the gatekeeper of the anthocyanin pathway [8]. Enzymes of chalcone synthase (CHS) are member of the plants-specific type III polyketide synthase (PKS) [9,10], family and catalyze the first committed step of the branch of the phenylpropanoid pathway, which leads to the synthesis of flavonoids [11,12]. Flavonoids are well known as a group of plant secondary metabolites that comprise several different classes of compounds, such as chalcones, flavones, flavonol isoflavones and anthocyanins.…”

Molecular cloning and functional analysis of 4-coumarate: CoA ligases from Marchantia paleacea and their roles in lignin and flavanone biosynthesis

“…Previous studies have suggested that naringenin biosynthesis from p -coumaroyl CoA, which is catalyzed by CHS, is the limiting step for flavonoid production [ 50 ]. To date, many CHSs have been characterized in plant species spanning Bryophyta [ 51 ], Pteridophyta [ 40 , 52 ], Gymnospermae, and Angiospermae [ 53 , 54 ]. In this study, we selected the chalcone synthases MpCHS (AUG98250.1) [ 55 ], Stenoloma chusanaum chalcone synthase (ScCHS1, ON462260) [ 40 ], and AtCHS (NP_196897.1) [ 56 ] for investigation by constructing three engineered strains, E1 (harboring MpCHS and Mp4CL1 ), E2 (harboring AtCHS and Mp4CL1 ), and E3 (harboring ScCHS1 and Mp4CL1 ) ( Fig 8A ).…”

Over-expression of KdSOC1 gene affected plantlet morphogenesis in Kalanchoe daigremontiana

“…KdSOC1 gene complete opening reading frame (ORF) cDNA sequence was introduced into pBIN438 35 plasmid driven by enhanced CaMV35s promoter as over-expression (OE) construct; RNAi construct of KdSOC1 gene was designed by introducing antisense and sense ORF of KdSOC1 gene into pZH01 36 plasmid with partial GUSA gene as intron between them; tissue expression construct of KdSOC1 gene ( PKdSOC1-GUS ) was designed by introducing its 1.2 kb promoter sequence to replace CaMV35s promoter in pBI121 37 plasmid and drives the expression of GUS gene (empty pBI121 plasmid [ 35S-GUS ] was used as positive control). Then all the plasmids mentioned above were all transformed in Agrobacterium tumefeciens strain LBA4404.…”