Binding of phytochrome B to its nuclear signalling partner PIF3 is reversibly induced by light

Min Ni, James M. Tepperman, Peter H. Quail

Research output: Contribution to journalArticlepeer-review

343 Scopus citations

Abstract

The phytochrome photoreceptor family directs plant gene expression by switching between biologically inactive and active conformers in response to the sequential absorption of red and farred photons. Several intermediates that act late in the phytochrome signalling pathway have been identified, but fewer have been identified that act early in the pathway. We have cloned a nuclear basic helix-loop-helix protein, PIF3, which can bind to non- photoactive carboxy-terminal fragments of phytochromes A and B and functions in phytochrome signalling in vivo. Here we show that full-length photoactive phytochrome B binds PIF3 in vitro only upon light-induced conversion to its active form, and that photoconversion back to its inactive form causes dissociation from PIF3. We conclude that photosensory signalling by phytochrome B involves light-induced, conformer-specific recognition of the putative transcriptional regulator PIF3, providing a potential mechanism for direct photoregulation of gene expression.

Original languageEnglish (US)
Pages (from-to)781-784
Number of pages4
JournalNature
Volume400
Issue number6746
DOIs
StatePublished - Aug 19 1999

Fingerprint

Dive into the research topics of 'Binding of phytochrome B to its nuclear signalling partner PIF3 is reversibly induced by light'. Together they form a unique fingerprint.

Cite this