W-box and G-box elements play important roles in early senescence of rice flag leaf

Sci Rep. 2016 Feb 11:6:20881. doi: 10.1038/srep20881.

Abstract

Plant cis-elements play important roles in global regulation of gene expression. Based on microarray data from rice flag leaves during early senescence, we identified W-box and G-box cis-elements as positive regulators of senescence in the important rice variety Minghui 63. Both cis-elements were bound by leaf senescence-specific proteins in vitro and influenced senescence in vivo. Furthermore, combination of the two elements drove enhanced expression during leaf senescence, and copy numbers of the cis-elements significantly affected the levels of expression. The W-box is the cognate cis-element for WRKY proteins, while the G-box is the cognate cis-element for bZIP, bHLH and NAC proteins. Consistent with this, WRKY, bZIP, bHLH and NAC family members were overrepresented among transcription factor genes up-regulated according during senescence. Crosstalk between ABA, CTK, BR, auxin, GA and JA during senescence was uncovered by comparing expression patterns of senescence up-regulated transcription factors. Together, our results indicate that hormone-mediated signaling could converge on leaf senescence at the transcriptional level through W-box and G-box elements. Considering that there are very few documented early senescence-related cis-elements, our results significantly contribute to understanding the regulation of flag leaf senescence and provide prioritized targets for stay-green trait improvement.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclopentanes / metabolism
  • DNA Copy Number Variations
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant*
  • Gibberellins / metabolism
  • Indoleacetic Acids / metabolism
  • Microarray Analysis
  • Oryza / genetics*
  • Oryza / metabolism
  • Oxylipins / metabolism
  • Plant Growth Regulators / metabolism
  • Plant Leaves / genetics*
  • Plant Leaves / metabolism
  • Plant Proteins / genetics*
  • Plant Proteins / metabolism
  • Promoter Regions, Genetic
  • Quantitative Trait, Heritable
  • Regulatory Elements, Transcriptional*
  • Signal Transduction
  • Time Factors
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Transcription, Genetic

Substances

  • Cyclopentanes
  • Gibberellins
  • Indoleacetic Acids
  • Oxylipins
  • Plant Growth Regulators
  • Plant Proteins
  • Transcription Factors
  • jasmonic acid
  • gibberellic acid