Abstract:
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Arachis hypogaea is one of the major agricultural crops of Pakistan, the seed of which is
widely used as food and in the oil seed industry. The plant also accrues a number of
secondary metabolites that act as active ingredients such as flavonoids. Plant flavonoids
play a vital role in various biological processes. The current study is focus on
characterization of key regulators of flavonoid biosynthetic pathway in cultivated peanut
varieties of Pakistan, focusing on the genes encoding enzymes for the biosynthetic
reactions. In current study nine structural genes have been identified in flavonoid
biosynthetic pathway in Arachis hypogaea including full length cDNAs of cinnamate-4-
hydroxylase (AhC4H), 4-hydroxycinnamoyl-CoA ligase 3 (Ah4CL3), chalcone synthase
(AhCHS), chalcone isomerase, flavonone 3-hydroxylase (AhF3H), dihydroflavonol 4-
reductase (AhDFR), flavonol synthase (AhFLS), leucoanthocyanidin reductase (AhLAR)
and anthocyanidin synthase (AhANS) and NCBI and peanut EST database has been used
in this study, along with Arabidopsis gene database from NCBI was used as
reference.Genomic annotation was made according to sequence similarities and later
expression profiling of the representative genes have been done after induction of elicitor,
drought stress. Furthermore, in silico analysis revealed those proteins of all candidate genes
have conserved domains. Relative expression analysis showed that expression of these
genes was induced by abiotic stress, i. e. drought. Core promoter region and cis-regulatory
elements are also identified using computational methods. Candidate promotors are
correlated to genomic features and expression analysis data from structural genes of
flavonoid biosynthetic pathway. Furthermore, eight transcription factors MYB7, MYB111,
MYB123, bHLH042, EGL3, GL3, COP1, CSU2 has been identified in Arachis hypogaea
genome mainly belongs to MYB family bHLH and WD40 family. This study would
provide a better understanding of the underlying molecular mechanism of flavonoid
biosynthetic pathway in Arachis hypogaea.
