The fully linked HTML version of this article has now been published.
Development ePress online publication date 23 Apr 2008
doi: 10.1242/dev.016873
Research article
The TTG1-bHLH-MYB complex controls trichome cell fate and patterning through direct targeting of regulatory loci
Mingzhe Zhao,
Kengo Morohashi,
Greg Hatlestad,
Erich Grotewold,
and
Alan Lloyd*
* Author for correspondence (e-mail: lloyd{at}uts.cc.utexas.edu)
A network of three classes of proteins consisting of bHLH and MYB transcription factors, and a WD40 repeat protein, TRANSPARENT TESTA GLABRA1 (TTG1), act in concert to activate trichome initiation and patterning. Using YFP-TTG1 translational fusions, we show that TTG1 is expressed ubiquitously in Arabidopsis leaves and is preferentially localized in the nuclei of trichomes at all developmental stages. Using a conditional transgenic allele, we demonstrate that TTG1 directly targets the same genes as the bHLH protein GLABRA3 (GL3). In vivo binding of the R2R3-MYB protein GLABRA1 (GL1) to the promoters of GLABRA2 (GL2), TRANSPARENT TESTA GLABRA2 (TTG2), CAPRICE (CPC) and ENHANCER OF TRIPTYCHON AND CAPRICE1 (ETC1) establishes that these genes are major transcriptional targets for the TTG1-bHLH-MYB regulatory complex. By co-precipitation, we confirm that TTG1 associates with GL3 and GL1 in vivo, forming a complex. The loss of TTG1 and GL1 through mutation, affects the subcellular distribution of GL3. Using particle bombardment, we show that TTG1, GL3, GL1 and the homeodomain protein GL2 do not move between adjacent epidermal cells, while the R3-MYB, CPC, does move to neighboring cells. These data support a model for the TTG1 complex directly regulating activators and repressors and the movement of repressors to affect trichome patterning on the Arabidopsis leaf.

CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati
Twitter What's this?
This article has been cited by other articles:

|
 |

|
 |
 
Y. Pang, J. P. Wenger, K. Saathoff, G. J. Peel, J. Wen, D. Huhman, S. N. Allen, Y. Tang, X. Cheng, M. Tadege, et al.
A WD40 Repeat Protein from Medicago truncatula Is Necessary for Tissue-Specific Anthocyanin and Proanthocyanidin Biosynthesis But Not for Trichome Development
Plant Physiology,
November 1, 2009;
151(3):
1114 - 1129.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. Wang, R. Liu, L. Chen, Y. Wang, Y. Liang, X. Wu, B. Li, J. Wu, Y. Liang, X. Wang, et al.
Nicotiana tabacum TTG1 contributes to ParA1-induced signalling and cell death in leaf trichomes
J. Cell Sci.,
August 1, 2009;
122(15):
2673 - 2685.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Breuer, A. Kawamura, T. Ichikawa, R. Tominaga-Wada, T. Wada, Y. Kondou, S. Muto, M. Matsui, and K. Sugimoto
The Trihelix Transcription Factor GTL1 Regulates Ploidy-Dependent Cell Growth in the Arabidopsis Trichome
PLANT CELL,
August 1, 2009;
21(8):
2307 - 2322.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H.-F. Zhu, K. Fitzsimmons, A. Khandelwal, and R. G. Kranz
CPC, a Single-Repeat R3 MYB, Is a Negative Regulator of Anthocyanin Biosynthesis in Arabidopsis
Mol Plant,
July 1, 2009;
2(4):
790 - 802.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. D. Marks, J. P. Wenger, E. Gilding, R. Jilk, and R. A. Dixon
Transcriptome Analysis of Arabidopsis Wild-Type and gl3-sst sim Trichomes Identifies Four Additional Genes Required for Trichome Development
Mol Plant,
July 1, 2009;
2(4):
803 - 822.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. Yoshida, R. Sano, T. Wada, J. Takabayashi, and K. Okada
Jasmonic acid control of GLABRA3 links inducible defense and trichome patterning in Arabidopsis
Development,
March 15, 2009;
136(6):
1039 - 1048.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Wang and J.-G. Chen
Arabidopsis Transient Expression Analysis Reveals that Activation of GLABRA2 May Require Concurrent Binding of GLABRA1 and GLABRA3 to the Promoter of GLABRA2
Plant Cell Physiol.,
December 1, 2008;
49(12):
1792 - 1804.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. J. Jakoby, D. Falkenhan, M. T. Mader, G. Brininstool, E. Wischnitzki, N. Platz, A. Hudson, M. Hulskamp, J. Larkin, and A. Schnittger
Transcriptional Profiling of Mature Arabidopsis Trichomes Reveals That NOECK Encodes the MIXTA-Like Transcriptional Regulator MYB106
Plant Physiology,
November 1, 2008;
148(3):
1583 - 1602.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J.-F. Wu, Y. Wang, and S.-H. Wu
Two New Clock Proteins, LWD1 and LWD2, Regulate Arabidopsis Photoperiodic Flowering
Plant Physiology,
October 1, 2008;
148(2):
948 - 959.
[Abstract]
[Full Text]
[PDF]
|
 |
|
© The Company of Biologists Ltd 2008