Molecular Characterization and Comparative Transcriptomic Analysis of Hr-Lcyb and Hr-Psy Genes for Carotenoids Synthesis in Sea Buckthorn (Hippophae rhamnoides L.)

Sea buckthorn (Hippophae rhamnoides) is an important medicinal plant of Southeast-Asia, enriched with various antioxidant components like β-carotene, alpha-tocopherol, catechin and folacin. Carotenoids are the bioactive substances abundantly present in sea buckthorn berries providing it an enticing yellowish, or orange red color. We performed the phylogenetic analysis, and conserved domain analysis to observe the evolutionary history and functional cites of carotenoids biosynthesis genes respectively. Further relative expression of two carotenoids biosynthesis genes Lycopene β-cyclase (Hr-Lcyb) and phytoene synthase (Hr-Psy) in was conducted in various tissues of sea buckthorn plants. Our results revealed that both the carotenoid synthesis genes Hr-Lcyb and Hr-Psy showed homology with already reported Arabidopsis thaliana genes (AT3G10230 and AT5G17230). Relative expression analysis indicated that expression of Hr-Lcyb and Hr-Psy genes in leaves and floral organs of sea buckthorn was one-fold higher than other tissues. This study will open the door for plant biologists for further characterization of carotenoids synthesis genes and their regulatory processes in specific tissues of carotenoid rich fruit plants.