Identification of Functional Single Nucleotide Polymorphism of Populus trichocarpa PtrEPSP-TF and Determination of its Transcriptional Effect

Crissa Doeppke, Mark Davis, Meng Xie, Jin Zhang, Vasanth Singan, Melissa McGranahan, Peter LaFayette, Sara Jawdy, Nancy Engle, Timothy Tschaplinski, Erika Lindquist, Kerrie Barry, Jeremy Schmutz, Wayne Parrott, Feng Chen, Gerald Tuskan, Jin-Gui Chen, Wellington Muchero

Research output: Contribution to journalArticlepeer-review

4 Scopus Citations


In plants, the phenylpropanoid pathway is responsible for the synthesis of a diverse array of secondary metabolites that include lignin monomers, flavonoids, and coumarins, many of which are essential for plant structure, biomass recalcitrance, stress defense, and nutritional quality. Our previous studies have demonstrated that Populus trichocarpa PtrEPSP-TF, an isoform of 5-enolpyruvylshikimate 3-phosphate (EPSP) synthase, has transcriptional activity and regulates phenylpropanoid biosynthesis in Populus. In this study, we report the identification of single nucleotide polymorphism (SNP) of PtrEPSP-TF that defines its functionality. Populus natural variants carrying this SNP were shown to have reduced lignin content. Here, we demonstrated that the SNP-induced substitution of 142nd amino acid (PtrEPSP-TFD142E) dramatically impairs the DNA-binding and transcriptional activity of PtrEPSP-TF. When introduced to a monocot species rice (Oryza sativa) in which an EPSP synthase isoform with the DNA-binding helix-turn-helix (HTH) motif is absent, the PtrEPSP-TF, but not PtrEPSP-TFD142E, activated genes in the phenylpropanoid pathway. More importantly, heterologous expression of PtrEPSP-TF uncovered five new transcriptional regulators of phenylpropanoid biosynthesis in rice. Collectively, this study identifies the key amino acid required for PtrEPSP-TF functionality and provides a strategy to uncover new transcriptional regulators in phenylpropanoid biosynthesis.

Original languageAmerican English
Article numbere00178
Number of pages13
JournalPlant Direct
Issue number1
StatePublished - 2020

Bibliographical note

Publisher Copyright:
© 2020 The Authors. Plant Direct published by American Society of Plant Biologists, Society for Experimental Biology and John Wiley & Sons Ltd.

NREL Publication Number

  • NREL/JA-2700-75861


  • DNA binding
  • EPSP synthase
  • phenylpropanoid
  • rice
  • transcriptional regulation


Dive into the research topics of 'Identification of Functional Single Nucleotide Polymorphism of Populus trichocarpa PtrEPSP-TF and Determination of its Transcriptional Effect'. Together they form a unique fingerprint.

Cite this