LHY and CCA1 are partially redundant genes required to maintain circadian rhythms in Arabidopsis.

By T. Mizoguchi, Kay Wheatley, Y. Hanzawa, L. Wright, Mutsuko Mizoguchi, Hae-Ryong Song, I. Carré, G. Coupland. Developmental Cell, 2002

633 citations recorded by the source corpus.

Several genes are known to regulate circadian rhythms in Arabidopsis, but the identity of the central oscillator has not been established. LHY and CCA1 are related MYB-like transcription factors proposed to be closely involved. Here we demonstrate that, as shown previously for CCA1, inactivation of LHY shortens the period of circadian rhythms in gene expression and leaf movements. By constructing lhy cca1-1 double mutants, we show that LHY and CCA1 are partially redundant and essential for the maintenance of circadian rhythms in constant light. Under light/dark cycles the lhy cca1-1 plants show dramatically earlier phases of expression of GI and TOC1, genes associated with the generation of circadian rhythms and the promotion of LHY and CCA1 expression. We conclude that LHY and CCA1 appear to be negative regulatory elements required for central oscillator function.

Subfields: Molecular Biology, Plant Science

View Paper: https://www.semanticscholar.org/paper/4d0f433ea6524a7689787e590b3c370ded9117a5

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Molecular Biology

1. Z. J. Chen
2. Alison M. Smith
3. C. R. McClung
4. G. Coupland
5. Mark Stitt
6. X. Deng
7. Yuling Jiao
8. O. Lau

In Plant Science

1. Z. J. Chen
2. Alison M. Smith
3. C. R. McClung
4. G. Coupland
5. Mark Stitt
6. X. Deng
7. Yuling Jiao
8. O. Lau

Citations in the corpus

• Control of flowering time: interacting pathways as a basis for diversity. (2002, background): “Loss-of-function alleles of LHY or CCA1 cause circadian period length to be shortened by 3 h, and inactivation of both genes prevents the maintenance of circadian rhythms under constant conditions (Green and Tobin, 1999; Mizoguchi et al., 2002).”
• Circadian control of carbohydrate availability for growth in Arabidopsis plants at night (2010, background): “The clock in cca1/lhy seedlings has a short free-running period of about 17 h under continuous light (14, 17, 18).”
• The MYB Transcription Factor Superfamily of Arabidopsis: Expression Analysis and Phylogenetic Comparison with the Rice MYB Family (2005, background): “genes involved in the maintenance of circadian rhythms (Schaffer et al., 1998; Wang and Tobin, 1998; Green and Tobin, 1999; Alabadi et al., 2001; Mizoguchi et al., 2002; Kuno et al., 2003), and CPC-like genes involved in control of cellular morphogenesis (Kirik and Baumlein, 1996; Wada et al.”
• Plant Circadian Rhythms (2006, background): “Several other genes, including GIGANTEA (GI), EARLY FLOWERING3 (ELF3), ELF4, and LUX, are required for CCA1 and LHY expression (Park et al., 1999; Doyle et al., 2002; Mizoguchi et al., 2002; Hazen et al., 2005).”
• Molecular mechanisms of polyploidy and hybrid vigor (2010, background): “In the hybrids, the allelic interactions between parent 1 (P1) and parent 2 (P2) induce epigenetic repression of CCA1 and LHY expression amplitudes (red dashed line) and upregulation of TOC1 expression amplitudes (green dashed line) relative to the expression values in the parents (solid red and gre”
• Light-regulated transcriptional networks in higher plants (2007, background): “Similarly, EARLY FLOWERING 4 (ELF4), GIGANTEA (GI) and LUX ARRHYTHMO (LUX; also known as PCL1) are thought to form feedback loops with CCA1/LH”
• Shade Avoidance (2012, neutral): “…rhythms fail to respond to sunflecks even in the afternoon while the late elongated hypocotyl (lhy) circadian clock associated 1 (cca1) double mutant (Mizoguchi et al., 2002) shows a slightly higher response to morning sunflecks but it retains the higher effectiveness of afternoon sunflecks.”