First published online August 12, 2004; 10.1105/tpc.104.024216
The Plant Cell 16:2293-2306 (2004)
© 2004 American Society of Plant Biologists
The SPA Quartet: A Family of WD-Repeat Proteins with a Central Role in Suppression of Photomorphogenesis in Arabidopsis
Sascha Laubinger,
Kirsten Fittinghoff and
Ute Hoecker1
Department of Plant Developmental and Molecular Biology, University of Düsseldorf, D-40225 Düsseldorf, Germany
1 To whom correspondence should be addressed. E-mail hoeckeru{at}uni-duesseldorf.de; fax 49-211-8114871.
The Arabidopsis thaliana proteins suppressor of phytochrome A-105 1 (SPA1), SPA3, and SPA4 of the four-member SPA1 protein family have been shown to repress photomorphogenesis in light-grown seedlings. Here, we demonstrate that spa quadruple mutant seedlings with defects in SPA1, SPA2, SPA3, and SPA4 undergo strong constitutive photomorphogenesis in the dark. Consistent with this finding, adult spa quadruple mutants are extremely small and dwarfed. These extreme phenotypes are only observed when all SPA genes are mutated, indicating functional redundancy among SPA genes. Differential contributions of individual SPA genes were revealed by analysis of spa double and triple mutant genotypes. SPA1 and SPA2 predominate in dark-grown seedlings, whereas SPA3 and SPA4 prevalently regulate the elongation growth in adult plants. Further analysis of SPA2 function indicated that SPA2 is a potent repressor of photomorphogenesis only in the dark but not in the light. The SPA2 protein is constitutively nuclear localized in planta and can physically interact with the repressor COP1. Epistasis analysis between spa2 and cop1 mutations provides strong genetic support for a biological significance of a COP1–SPA2 interaction in the plant. Taken together, our results have identified a new family of proteins that is essential for suppression of photomorphogenesis in darkness.
This article has been cited by other articles:
|
|
|
|
 
D. Zhu, A. Maier, J.-H. Lee, S. Laubinger, Y. Saijo, H. Wang, L.-J. Qu, U. Hoecker, and X. W. Deng
Biochemical Characterization of Arabidopsis Complexes Containing CONSTITUTIVELY PHOTOMORPHOGENIC1 and SUPPRESSOR OF PHYA Proteins in Light Control of Plant Development
PLANT CELL,
September 1, 2008;
20(9):
2307 - 2323.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Bhatia, S. N. Gangappa, R. Kushwaha, S. Kundu, and S. Chattopadhyay
SHORT HYPOCOTYL IN WHITE LIGHT1, a Serine-Arginine-Aspartate-Rich Protein in Arabidopsis, Acts as a Negative Regulator of Photomorphogenic Growth
Plant Physiology,
May 1, 2008;
147(1):
169 - 178.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
X. Chen, W.-H. Lin, Y. Wang, S. Luan, and H.-W. Xue
An Inositol Polyphosphate 5-Phosphatase Functions in PHOTOTROPIN1 Signaling in Arabidopis by Altering Cytosolic Ca2+
PLANT CELL,
February 1, 2008;
20(2):
353 - 366.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
R.-C. Lin, H.-J. Park, and H.-Y. Wang
Role of Arabidopsis RAP2.4 in Regulating Light- and Ethylene-Mediated Developmental Processes and Drought Stress Tolerance
Mol Plant,
January 1, 2008;
1(1):
42 - 57.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J.-H. Lee, W. Terzaghi, G. Gusmaroli, J.-B. F. Charron, H.-J. Yoon, H. Chen, Y. J. He, Y. Xiong, and X. W. Deng
Characterization of Arabidopsis and Rice DWD Proteins and Their Roles as Substrate Receptors for CUL4-RING E3 Ubiquitin Ligases
PLANT CELL,
January 1, 2008;
20(1):
152 - 167.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
Y. Kobayashi and D. Weigel
Move on up, it's time for change mobile signals controlling photoperiod-dependent flowering
Genes & Dev.,
October 1, 2007;
21(19):
2371 - 2384.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Laubinger, V. Marchal, J. Gentilhomme, S. Wenkel, J. Adrian, S. Jang, C. Kulajta, H. Braun, G. Coupland, and U. Hoecker
Arabidopsis SPA proteins regulate photoperiodic flowering and interact with the floral inducer CONSTANS to regulate its stability
Development,
August 15, 2006;
133(16):
3213 - 3222.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
C. Mallappa, V. Yadav, P. Negi, and S. Chattopadhyay
A Basic Leucine Zipper Transcription Factor, G-box-binding Factor 1, Regulates Blue Light-mediated Photomorphogenic Growth in Arabidopsis
J. Biol. Chem.,
August 4, 2006;
281(31):
22190 - 22199.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. Oravecz, A. Baumann, Z. Mate, A. Brzezinska, J. Molinier, E. J. Oakeley, E. Adam, E. Schafer, F. Nagy, and R. Ulm
CONSTITUTIVELY PHOTOMORPHOGENIC1 Is Required for the UV-B Response in Arabidopsis
PLANT CELL,
August 1, 2006;
18(8):
1975 - 1990.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
V. Yadav, C. Mallappa, S. N. Gangappa, S. Bhatia, and S. Chattopadhyay
A Basic Helix-Loop-Helix Transcription Factor in Arabidopsis, MYC2, Acts as a Repressor of Blue Light-Mediated Photomorphogenic Growth
PLANT CELL,
July 1, 2005;
17(7):
1953 - 1966.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Yang, R. Lin, J. Sullivan, U. Hoecker, B. Liu, L. Xu, X. W. Deng, and H. Wang
Light Regulates COP1-Mediated Degradation of HFR1, a Transcription Factor Essential for Light Signaling in Arabidopsis
PLANT CELL,
March 1, 2005;
17(3):
804 - 821.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Moon, G. Parry, and M. Estelle
The Ubiquitin-Proteasome Pathway and Plant Development
PLANT CELL,
December 1, 2004;
16(12):
3181 - 3195.
[Full Text]
[PDF]
|
|
|
|
|
