Phytochromes and Phytochrome Interacting Factors

Plant Physiol. 2018 Feb;176(2):1025-1038. doi: 10.1104/pp.17.01384. Epub 2017 Nov 14.


The basic helix-loop-helix domain-containing transcription factors that interact physically with the red and far-red light photoreceptors, phytochromes, are called PHYTOCHROME INTERACTING FACTORS (PIFs). In the last two decades, the phytochrome-PIF signaling module has been shown to be conserved from Physcomitrella patens to higher plants. Exciting recent studies highlight the discovery of at least four distinct kinases (PPKs, CK2, BIN2, and phytochrome itself) and four families of ubiquitin ligases (SCFEBF1/2, CUL3LRB, CUL3BOP, and CUL4COP1-SPA) that regulate PIF abundance both in dark and light conditions. This review discusses these recent discoveries with a focus on the central phytochrome signaling mechanisms that have a profound impact on plant growth and development in response to light.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Basic Helix-Loop-Helix Transcription Factors / genetics
  • Basic Helix-Loop-Helix Transcription Factors / metabolism*
  • Gene Expression Regulation, Plant / radiation effects
  • Light
  • Phosphorylation / radiation effects
  • Phytochrome / genetics
  • Phytochrome / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plants / classification
  • Plants / genetics
  • Plants / metabolism*
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Proteolysis / radiation effects


  • Basic Helix-Loop-Helix Transcription Factors
  • Plant Proteins
  • Protein Isoforms
  • Phytochrome