|
Overexpression of a Homeobox Gene, LeT6,
Reveals Indeterminate Features in the Tomato Compound
Leaf1
Bart-Jan Janssen,
Lance Lund, and
Neelima Sinha*
Section of Plant Biology, University of California, Davis,
California 95616
The cultivated tomato
(Lycopersicon esculentum) has a unipinnate compound
leaf. In the developing leaf primordium, major leaflet initiation is
basipetal, and lobe formation and early vascular differentiation are
acropetal. We show that engineered alterations in the expression of a
tomato homeobox gene, LeT6, can cause dramatic changes
in leaf morphology. The morphological states are variable and unstable
and the phenotypes produced indicate that the tomato leaf has an
inherent level of indeterminacy. This is manifested by the production
of multiple orders of compounding in the leaf, by numerous shoot,
inflorescence, and floral meristems on leaves, and by the conversion of
rachis-petiolule junctions into "axillary" positions where floral
buds can arise. Overexpression of a heterologous homeobox transgene,
kn1, does not produce such phenotypic variability. This
indicates that LeT6 may differ from the heterologous
kn1 gene in the effects manifested on overexpression,
and that 35S-LeT6 plants may be subject to alterations
in expression of both the introduced and endogenous LeT6
genes. The expression patterns of LeT6 argue in favor of
a fundamental role for LeT6 in morphogenesis of leaves
in tomato and also suggest that variability in homeobox gene expression
may account for some of the diversity in leaf form seen in nature.
1
This work was funded by the National Science
Foundation (grant no. IBN-96-32013).
*
Corresponding author; e-mail nrsinha{at}ucdavis.edu; fax
1-530-752-5410.
Plant Physiol. (1998) 117: 771-786
Copyright Clearance Center: 0032-0889/98/117/0771/16
© 1998 American Society of Plant Physiologists
This article has been cited by other articles:

|
 |

|
 |
 
E. Shani, Y. Burko, L. Ben-Yaakov, Y. Berger, Z. Amsellem, A. Goldshmidt, E. Sharon, and N. Ori
Stage-Specific Regulation of Solanum lycopersicum Leaf Maturation by Class 1 KNOTTED1-LIKE HOMEOBOX Proteins
PLANT CELL,
October 1, 2009;
21(10):
3078 - 3092.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. David-Schwartz, D. Koenig, and N. R. Sinha
LYRATE Is a Key Regulator of Leaflet Initiation and Lamina Outgrowth in Tomato
PLANT CELL,
October 1, 2009;
21(10):
3093 - 3104.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. E.M. Champagne, T. E. Goliber, M. F. Wojciechowski, R. W. Mei, B. T. Townsley, K. Wang, M. M. Paz, R. Geeta, and N. R. Sinha
Compound Leaf Development and Evolution in the Legumes
PLANT CELL,
November 1, 2007;
19(11):
3369 - 3378.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
N. Uchida, B. Townsley, K.-H. Chung, and N. Sinha
Regulation of SHOOT MERISTEMLESS genes via an upstream-conserved noncoding sequence coordinates leaf development
PNAS,
October 2, 2007;
104(40):
15953 - 15958.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Koi and M. Kato
Developmental Morphology of the Shoot in Weddellina squamulosa and Implications for Shoot Evolution in the Podostemaceae
Ann. Bot.,
June 1, 2007;
99(6):
1121 - 1130.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. D. Tattersall, L. Turner, M. R. Knox, M. J. Ambrose, T.H. N. Ellis, and J. M.I. Hofer
The Mutant crispa Reveals Multiple Roles for PHANTASTICA in Pea Compound Leaf Development
PLANT CELL,
April 1, 2005;
17(4):
1046 - 1060.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
W. E. Friedman, R. C. Moore, and M. D. Purugganan
The evolution of plant development
Am. J. Botany,
October 1, 2004;
91(10):
1726 - 1741.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Champagne and N. Sinha
Compound leaves: equal to the sum of their parts?
Development,
September 15, 2004;
131(18):
4401 - 4412.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
N. A. McHale and R. E. Koning
MicroRNA-Directed Cleavage of Nicotiana sylvestris PHAVOLUTA mRNA Regulates the Vascular Cambium and Structure of Apical Meristems
PLANT CELL,
July 1, 2004;
16(7):
1730 - 1740.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Kim, T. Pham, A. Hamidi, S. McCormick, R. K. Kuzoff, and N. Sinha
Reduced leaf complexity in tomato wiry mutants suggests a role for PHAN and KNOX genes in generating compound leaves
Development,
September 15, 2003;
130(18):
4405 - 4415.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
F. M. Rosin, J. K. Hart, H. T. Horner, P. J. Davies, and D. J. Hannapel
Overexpression of a Knotted-Like Homeobox Gene of Potato Alters Vegetative Development by Decreasing Gibberellin Accumulation
Plant Physiology,
May 1, 2003;
132(1):
106 - 117.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Hay, D. Jackson, N. Ori, and S. Hake
Analysis of the Competence to Respond to KNOTTED1 Activity in Arabidopsis Leaves Using a Steroid Induction System
Plant Physiology,
April 1, 2003;
131(4):
1671 - 1680.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. F. Tioni, D. H. Gonzalez, and R. L. Chan
Knotted1-like genes are strongly expressed in differentiated cell types in sunflower
J. Exp. Bot.,
February 1, 2003;
54(383):
681 - 690.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. L. Micol and S. Hake
The Development of Plant Leaves
Plant Physiology,
February 1, 2003;
131(2):
389 - 394.
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Ampomah-Dwamena, B. A. Morris, P. Sutherland, B. Veit, and J.-L. Yao
Down-Regulation of TM29, a Tomato SEPALLATA Homolog, Causes Parthenocarpic Fruit Development and Floral Reversion
Plant Physiology,
October 1, 2002;
130(2):
605 - 617.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. Bharathan, T. E. Goliber, C. Moore, S. Kessler, T. Pham, and N. R. Sinha
Homologies in Leaf Form Inferred from KNOXI Gene Expression During Development
Science,
June 7, 2002;
296(5574):
1858 - 1860.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. Bharathan and N. R. Sinha
The Regulation of Compound Leaf Development
Plant Physiology,
December 1, 2001;
127(4):
1533 - 1538.
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Lu, Z. Zainal, G. A. Tucker, and G. W. Lycett
Developmental Abnormalities and Reduced Fruit Softening in Tomato Plants Expressing an Antisense Rab11 GTPase Gene
PLANT CELL,
August 1, 2001;
13(8):
1819 - 1833.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Kim, W. Canio, S. Kessler, and N. Sinha
Developmental Changes Due to Long-Distance Movement of a Homeobox Fusion Transcript in Tomato
Science,
July 13, 2001;
293(5528):
287 - 289.
[Abstract]
[Full Text]
|
 |
|

|
 |

|
 |
 
M. Tsiantis
Control of Shoot Cell Fate: Beyond Homeoboxes
PLANT CELL,
April 1, 2001;
13(4):
733 - 738.
[Full Text]
|
 |
|

|
 |

|
 |
 
Y. Avivi, S. Lev-Yadun, N. Morozova, L. Libs, L. Williams, J. Zhao, G. Varghese, and G. Grafi
Clausa, a Tomato Mutant with a Wide Range of Phenotypic Perturbations, Displays a Cell Type-Dependent Expression of the Homeobox Gene LeT6/TKn2
Plant Physiology,
October 1, 2000;
124(2):
541 - 552.
[Abstract]
[Full Text]
|
 |
|

|
 |

|
 |
 
C. W. Gourlay, J. M. I. Hofer, and T. H. N. Ellis
Pea Compound Leaf Architecture Is Regulated by Interactions among the Genes UNIFOLIATA, COCHLEATA, AFILA, and TENDRIL-LESS
PLANT CELL,
August 1, 2000;
12(8):
1279 - 1294.
[Abstract]
[Full Text]
|
 |
|

|
 |

|
 |
 
H. Koltai and D. M. Bird
High Throughput Cellular Localization of Specific Plant mRNAs by Liquid-Phase in Situ Reverse Transcription-Polymerase Chain Reaction of Tissue Sections
Plant Physiology,
August 1, 2000;
123(4):
1203 - 1212.
[Abstract]
[Full Text]
|
 |
|
|
|