De novo transcriptomic analysis of light-induced flavonoid pathway, transcription factors in the flower buds of Lonicera japonica

Abstract

Key message Transcriptomic analysis of the relationship between gene expression patterns and flavonoid contents in the flower buds of Lonicera japonica under light-induced conditions, especially the flavonoid pathway genes and transcription factors. Abstract Flos Lonicerae Japonicae (FLJ), the flower buds of Lonicera japonica Thunb., has been used to treat some human diseases including severe respiratory syndromes and hand-foot-and-mouth diseases owing to its putative antibacterial, and antiviral effects. Luteoloside is a flavonoid that is used by the Chinese Pharmacopoeia to evaluate the quality of FLJ. Light is an important environmental factor that affects flavonoid biosynthesis in the flower buds of L. japonica. However, how light triggers increases in flavonoid production remains unclear. To enhance our understanding of the mechanism involved in lightregulated flavonoid biosynthesis, we sequenced the transcriptomes of L. japonica exposed to three different light conditions: 100% light intensity (CK), 50% light intensity (LI50), and 25% light intensity (LI25) using an Illumina HiSeq 4000 System. A total of 77,297 unigenes with an average length of 809 bp were obtained. Among them, 43,334 unigenes (56.06%) could be matched to at least one biomolecular database. Additionally, 4188, 1545 and 1023 differentially expressed genes (DEGs) were identified by comparative transcriptomics LI25-vs-CK, LI50-vs-CK, and LI25-vs-LI50, respectively. Of note, genes known to be involved in flavonoid biosynthesis, such as 4-coumarate coenzyme A ligase (4CL), and chalcone synthase (CHS) were up-regulated. In addition, a total of 1649 transcription factors (TFs) were identified and divided into 58 TF families; 98 TFs exhibited highly dynamic changes in response to light intensity. Quantitative real-time PCR (qRT-PCR) was used to test the expression profiles of the RNA sequencing (RNA-Seq) data. This study offers insight into how transcriptional expression pattern is influenced by light in the flower buds of L. japonica, and will enhance the understanding of molecular mechanisms of flavonoid biosynthesis in response to light in L. japonica.

Effects of Light on Secondary Metabolite Biosynthesis in Medicinal Plants

“…Similar to other physiological processes, the accumulation of SMs in medicinal plants is significantly affected by light intensity (Chen et al, 2017;Li et al, 2020). Generally, high light intensity promotes SM production in heliophytes, such as Ginkgo biloba (Xu et al, 2014), Lonicera japonica (Fang et al, 2020), Tabernaemontana pachysiphon (Hoft et al, 1996), and Andrographis paniculata (Saravanan et al, 2008), while low light intensity promotes SM production in sciophytes, such as Glechoma longituba (Zhang et al, 2015), Changium smyrnioides (Wang et al, 2017), Polygonum minus (Mohd Yusof et al, 2021), and Panax ginseng (Jung et al, 2020). Concentration and yield are two important parameters that should be considered for SM production in medicinal plants.…”

Carbon and nitrogen metabolism under nitrogen variation affects flavonoid accumulation in the leaves of Coreopsis tinctoria

“…The biosynthesis of flavonoids is complex and subject to environmental conditions, such as temperature ( Gouot et al, 2019 ), light ( Fang et al, 2020 ) and mineral nutrition ( Scheible et al, 2004 ). The availability of mineral elements, especially nitrogen (N), is thought to be involved in regulating plant growth metabolic balance ( Jozef et al, 2007 ).…”

Potential Application of Lonicera japonica Extracts in Animal Production: From the Perspective of Intestinal Health

“…Lonicera japonica , also known as Japanese honeysuckle, Jin YinHua or Ren Dong, belongs to the member of the Caprifoliaceae family, is a perennial deciduous shrub native to East Asia and spread throughout Argentina, Brazil, Mexico, Australia, New Zealand, and American ( Kim et al, 2015 ). Traditionally, the flower bud of L. japonica , which has been listed in the Chinese Pharmacopeia as L. japonica Flos, is a traditional Chinese medicine that reportedly has antioxidant, anti-inflammatory, antibacterial, antiviral, antitumor, and antidiabetic properties ( Liu Z. et al, 2016 ; Shi et al, 2016 ; Wang et al, 2017 ), which has been widely used for preventing and treating influenza, cold, fever, and infections ( Kashiwada et al, 2013 ; Ge et al, 2018 ; Fang et al, 2020 ). Lonicera japonica extract is extracted from L. japonica , has complicated chemical composition.…”

“…The main flavones including cynaroside, luteolin, chrysoeriol 7-O-neohesperidoside, chrysoeriol 7-O-glucoside, lonicerin, tricin, etc. ( Choi et al, 2007 ; Lee et al, 2010 ; Ge et al, 2019 ; Fang et al, 2020 ). Other flavonoids including one flavonolignan (hydnocarpin), one flavanone (eriodictyol) and three biflavonoids [3'-O-methyl loniflavone (5,5'',7,7''-tetrahydroxy 3'-methoxy4',4'''-biflavonyl ether), loniflavone (5,5'',7,7'',30-pentahydroxy 4',4'''-biflavonyl ether) and (5,7,8,4'-tetrahydroxyflavone)-3'-4-(5,7-dihydroxyflavone)] were also have been isolated and identified from L. japonica ( Kumar et al, 2005 ; Ge et al, 2018 ; Li et al, 2019 ).…”

“…In addition to its medicinal uses, L. japonica is also widely used in healthy foods and cosmetics in the world because of its health benefits ( Seo et al, 2012 ; Fang et al, 2020 ; Zhang T. et al, 2020 ). Modern pharmacological researches have demonstrated that L. japonica extract has a variety of biological activities, which the antioxidant activity is an important biological property of great interest ( Hsu et al, 2016 ; Wan H. et al, 2019 ; Zhang T. et al, 2020 ).…”