Elucidation and functional characterization of CsPSY and CsUGT promoters in Crocus sativus L.

Abstract

The dried stigmas of Crocus sativus constitute the saffron, which is considered to be the costliest spice of the world. Saffron is valuable for its constituents, which are mainly apocarotenoids. In order to enhance the production of apocarotenoids, it is imperative to understand the regulation of apocarotenoid biosynthetic pathway. In C. sativus, although the pathway has been elucidated, the information regarding the regulation of the pathwaygenes is scanty. During the present investigation, the characterization of promoters regulating the expression of two important genes i.e. CsPSY and CsUGT was performed. We successfully cloned the promoters of both the genes, which were functionally characterized in Crocus sativus and Nicotiana tabaccum. In silico analysis of the promoters demonstrated the presence of several important cis regulatory elements responding tolight, hormonesand interaction with transcription factors (TFs). Further analysis suggested the regulation of CsPSY promoter by Abscisic acid (ABA) and that of CsUGT by Gibberellic acid (GA). In addition, we also observed ABA and GA mediated modulation in the expression of significant TFs and CsPSY and CsUGT transcripts. Overall, the study addresses issues related to regulation of key genes of apocarotenoid pathway in C.sativus.

Co-regulatory network analysis of the main secondary metabolite (SM) biosynthesis in Crocus sativus L.

“…Network analysis using WGCNA can reveal new insights into relationships across candidate transcription factors and metabolic profiles 37 . Most of the research on the C. sativus plant is related to gene expression profiles and secondary metabolites content analysis 23 , 38 – 41 , Even though, the secondary metabolite biosynthesis pathways have been addressed in some studies 21 , 42 , 43 . However, the basic mechanisms of the co-regulation and network analysis of the apocarotenoids biosynthesis pathway in C. sativus are still limited.…”

Deciphering the role of codon usage bias on gene expression and pathogen colonization in Crocus sativus

“…Most investigations on monocot species were focused on grasses however the con guration of codon usage could not be extrapolated for other monocot species. Among the monocots, C. sativus is a prominent member of family iridiceae, cultivated mostly for its valuable desiccated stigma that forms the saffron (Bhat et al 2018; Kothari et al 2021). Saffron has been considered as an important medicinal herb since long.…”