LIP1 Regulates the Plant Circadian Oscillator by Modulating the Function of the Clock Component GIGANTEA

Circadian clocks are biochemical timers regulating many physiological and molecular processes according to the day/night cycles. The function of the oscillator relies on negative transcriptional/translational feedback loops operated by the so-called clock genes and the encoded clock proteins. Previo...

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Bibliographic Details
Main Authors: Hajdu Anita
Nyári Dóra Vivien
Terecskei Kata
Gyula Péter
Ádám Éva
Dobos Orsolya
Mérai Zsuzsanna
Kozma-Bognár László
Format: Article
Published: 2024
Series:CELLS 13 No. 17
Subjects:
doi:10.3390/cells13171503

mtmt:35415164
Online Access:http://publicatio.bibl.u-szeged.hu/34722
Description
Summary:Circadian clocks are biochemical timers regulating many physiological and molecular processes according to the day/night cycles. The function of the oscillator relies on negative transcriptional/translational feedback loops operated by the so-called clock genes and the encoded clock proteins. Previously, we identified the small GTPase LIGHT INSENSITIVE PERIOD 1 (LIP1) as a circadian-clock-associated protein that regulates light input to the clock in the model plant Arabidopsis thaliana. We showed that LIP1 is also required for suppressing red and blue light-mediated photomorphogenesis, pavement cell shape determination and tolerance to salt stress. Here, we demonstrate that LIP1 is present in a complex of clock proteins GIGANTEA (GI), ZEITLUPE (ZTL) and TIMING OF CAB 1 (TOC1). LIP1 participates in this complex via GUANINE EX-CHANGE FACTOR 7. Analysis of genetic interactions proved that LIP1 affects the oscillator via modulating the function of GI. We show that LIP1 and GI independently and additively regulate photomorphogenesis and salt stress responses, whereas controlling cell shape and photoperiodic flowering are not shared functions of LIP1 and GI. Collectively, our results suggest that LIP1 affects a specific function of GI, possibly by altering binding of GI to downstream signalling components.
Physical Description:17
ISSN:2073-4409