Jul 31, 2023 · PIFs are known to regulate seed germination via interaction with phytochromes or through the regulation of the metabolism of hormones related to seed germination. The phyA promotes seed germination in very low light fluence response (VLFR) and phyB promotes germination in low light fluence response (LFR) [55].

Phytochrome B (phyB) inhibits the function of phytochrome-interacting factors (PIFs) by inducing their degradation and sequestration, but the relative physiological importance of these two phyB activities is unclear.

Nov 19, 2019 · In land plants, phytochromes are red and far-red light receptors that exist in two forms. They are synthesized in the inactive Pr state, which upon light absorption converts to the active Pfr...

Sep 16, 2019 · Here we show that SPA1 acts as a serine/threonine kinase and directly phosphorylates PIF1 in vitro and in vivo. SPAs are necessary for the light-induced phosphorylation, ubiquitination and...

Feb 1, 2022 · Light-activated phytochromes (PHYA and PHYB) bind directly to these PIF proteins which are then phosphorylated, followed by their rapid degradation and the reversal of their activities. This precise control of photomorphogenesis has been the subject of …

Jan 1, 2022 · Plants perceive changes in the red/far-red light ratio through the receptors for red/far-red light (R/FR)-Phytochrome (PHY) and transmit then the signal downstream. At present, five different phytochromes have been identified in higher plants (i.e., phyA through phyE; Fig. 1) (Pham et al., 2018).

Oct 30, 2024 · Phytochrome-interacting factors (PIFs) are a subgroup of transcription factors within the basic helix-loop-helix (bHLH) family, playing a crucial role in integrating various environmental signals to regulate plant growth and development.

Mar 18, 2021 · We characterized the functions of PHYB genes and their downstream PHYTOCHROME INTERACTING FACTOR (PIF) targets in the regulation of shade avoidance and seasonal growth in hybrid aspen trees.

Sep 23, 2024 · Phytochrome B (phyB) and phytochrome-interacting factors (PIFs) constitute a well-established signaling module critical for plants adapting to ambient light. However, mechanisms underlying phyB photoactivation and PIF binding for …

Feb 26, 2014 · PHYA and PHYB trigger PIF degradation on red light perception, and blue light represses PIF4 and PIF5 transcription in a PHOT1- and PHOT2-dependent manner. These factors facilitate nuclear translocation of PHYB and, under prolonged light, promote COP1-mediated destabilization of this photoreceptor.