HEXOKINASE-dependent regulation of WRKY transcription factors in Arabidopsis

Abstract

AbstractSugars are the major product of photosynthesis and provide the stored energy and basic building blocks for all living cells. Sugars also act as dynamic signals throughout the plant life cycle to regulate growth, development and interactions with the biotic and abiotic environment. From a previous RNA-seq experiment, we have identified eight sugar-regulatedWRKYtranscription factor genes. Focusing on four, we find thatWRKY11, WRKY17, WRKY60andWRKY72are upregulated by sucrose, glucose or fructose by a superoxide signalling pathway.WRKYgene expression is downregulated by 2-deoxyglucose (2-DG) or mannose, which are inhibitors of hexokinase (HXK), and inhxk1-3mutants. Mutants inWRKY17, WRKY60orWRKY72have reduced hypocotyl growth in response to sucrose, but do not have altered circadian period. Our data suggest that HXK1-dependent regulation ofWRKYgenes by sugars represents a superoxide-activated transcriptional subnetwork that influences plant growth.HighlightWRKY11, WRKY17, WRKY60andWRKY72are upregulated by a sugar-activated superoxide signalling pathway in a HKX1-dependent manner. These sugar-regulatedWRKYsrepresent a transcriptional subnetwork promoting plant growth.