Journal Article

Characterization of GaWRKY1, a cotton transcription factor that regulates the sesquiterpene synthase gene (+)-delta-cadinene synthase-A

Chen, X.Y, Wang, J.W, Xu, Y.H, Wang, S, Wang, J.Y

2004

Overview

The cotton (+)-delta-cadinene synthase (CAD1), a sesquiterpene cyclase, catalyzes a branch-point step leading to biosynthesis of sesquiterpene phytoalexins, including gossypol. CAD1-A is a member of CAD1 gene family, and its promoter contains a W-box palindrome with two reversely oriented TGAC repeats, which are the proposed binding sites of WRKY transcription factors. We isolated several WRKY cDNAs from Gossypium arboreum. One of them, GaWRKY1, encodes a protein containing a single WRKY domain and a putative N-terminal Leu zipper. Similar to genes encoding enzymes of cotton sesquiterpene pathway, GaWRKY1 was down-regulated in a glandless cotton cultivar that contained much less gossypol. GaWRKY1 showed a temporal and spatial pattern of expression comparable to that of CAD1-A in various aerial organs examined, including sepal, stigma, anther, and developing seeds. In suspension cells, expression of both GaWRKY1 and CAD1-A genes and biosynthesis of sesquiterpene aldehydes were strongly induced by a fungal elicitor preparation and methyl jasmonate. GaWRKY1 interacted with the 3 x W-box derived from CAD1-A promoter in yeast (Saccharomyces cerevisiae) one-hybrid system and in vitro. Furthermore, in transgenic Arabidopsis plants, overexpression of GaWRKY1 highly activated the CAD1-A promoter, and transient assay in tobacco (Nicotiana tabacum) leaves demonstrated that W-box was required for this activation. These results suggest that GaWRKY1 participates in regulation of sesquiterpene biosynthesis in cotton, and CAD1-A is a target gene of this transcription factor.

• Publisher: American Society of Plant Biologists,American Society of Plant Physiologists
• Subject: Acetates / Acetates - pharmacology / Agronomy. Soil science and plant productions / Amino Acid Sequence / amino acid sequences / Anthers / Biological and medical sciences / Biosynthesis / cadinene synthase A / Calyx / Carbon-Carbon Lyases / Carbon-Carbon Lyases - genetics / Carbon-Carbon Lyases - metabolism / chemistry / Classical and quantitative genetics. Population genetics. Molecular genetics / complementary DNA / cotton / Cyclopentanes / Cyclopentanes - pharmacology / delta-cadinene synthase / DNA, Complementary / DNA, Complementary - chemistry / DNA, Complementary - genetics / DNA-binding proteins / DNA-Binding Proteins - genetics / DNA-Binding Proteins - metabolism / drug effects / Enzyme Activation / Enzyme Activation - drug effects / Enzymes / enzymology / fiber crops / Fundamental and applied biological sciences. Psychology / Gene expression regulation / Gene Expression Regulation, Developmental / Gene Expression Regulation, Enzymologic / Gene Expression Regulation, Plant / Generalities. Genetics. Plant material / Genes / genetics / Genetics and breeding of economic plants / Gossypium / Gossypium - enzymology / Gossypium - genetics / Gossypium - microbiology / Gossypium arboreum / Gossypium hirsutum / Gossypol / Gossypol - metabolism / growth & development / host-pathogen relationships / Hydrogen Peroxide / Hydrogen Peroxide - pharmacology / Immunity, Innate / Immunity, Innate - genetics / Immunity, Innate - physiology / isomerases / Isomerases - genetics / Isomerases - metabolism / Metabolism / microbiology / Molecular genetics / Molecular Sequence Data / Nicotiana tabacum / nucleotide sequences / Oxylipins / pharmacology / physiology / Plant Diseases / Plant Diseases - genetics / Plant Diseases - microbiology / plant pathogenic fungi / Plant physiology and development / plant proteins / Plant Proteins - genetics / Plant Proteins - metabolism / Plants / Plants interacting with Other Organisms / promoter regions / Proteins / Reverse transcriptase polymerase chain reaction / Saccharomyces cerevisiae / Salicylic Acid / Salicylic Acid - pharmacology / sequence alignment / Sequence Analysis, DNA / Sequence Homology, Amino Acid / Sesquiterpenes / tobacco / Transcription factors / Transcription Factors - genetics / Transcription Factors - metabolism / transgenes / transgenic plants / Verticillium / Verticillium - growth & development / Verticillium dahliae