A novel two-component hybrid molecule regulates vascular morphogenesis of the Arabidopsis root.

The developmental ontogeny of the vascular system (consisting of xylem, phloem and [pro]cambium) is poorly understood despite its central role in plant physiology. We show that in the Arabidopsis root meristem, xylem cell lineages are specified early, whereas phloem and procambium are established through a set of asymmetric cell divisions. These divisions require the WOODEN LEG (WOL) gene. The WOL gene encodes a novel two-component signal transducer with an unusual tandem arrangement of two receiver domains. It is expressed specifically in the vasculature from the early stages of embryogenesis on, consistent with a role as a sensor for vascular morphogenesis.

[1]  S. Fujioka,et al.  A critical role of sterols in embryonic patterning and meristem programming revealed by the fackel mutants of Arabidopsis thaliana. , 2000, Genes & development.

[2]  S. Clough,et al.  Floral dip: a simplified method for Agrobacterium-mediated transformation of Arabidopsis thaliana. , 1998, The Plant journal : for cell and molecular biology.

[3]  K. Koizumi,et al.  A series of novel mutants of Arabidopsis thaliana that are defective in the formation of continuous vascular network: calling the auxin signal flow canalization hypothesis into question. , 2000, Development.

[4]  P. Benfey,et al.  The SCARECROW Gene Regulates an Asymmetric Cell Division That Is Essential for Generating the Radial Organization of the Arabidopsis Root , 1996, Cell.

[5]  Claud L. Brown.  The Influence of External Pressure on the Differentiation of Cells and Tissues Cultured in Vitro , 1964 .

[6]  R. Datla,et al.  Modified binary plant transformation vectors with the wild-type gene encoding NPTII. , 1992, Gene.

[7]  E. Meyerowitz,et al.  Arabidopsis ethylene-response gene ETR1: similarity of product to two-component regulators. , 1993, Science.

[8]  M. Bevan,et al.  Binary Agrobacterium vectors for plant transformation. , 1984, Nucleic acids research.

[9]  C. Hardtke,et al.  The Arabidopsis gene MONOPTEROS encodes a transcription factor mediating embryo axis formation and vascular development , 1998, The EMBO journal.

[10]  Ana I. Caño-Delgado,et al.  The eli1 mutation reveals a link between cell expansion and secondary cell wall formation in Arabidopsis thaliana. , 2000, Development.

[11]  Ira Herskowitz,et al.  Mechanisms of asymmetric cell division: Two Bs or not two Bs, that is the question , 1992, Cell.

[12]  K. Okada,et al.  The Arabidopsis HY5 gene encodes a bZIP protein that regulates stimulus-induced development of root and hypocotyl. , 1997, Genes & development.

[13]  O. Olsson,et al.  Increased gibberellin biosynthesis in transgenic trees promotes growth, biomass production and xylem fiber length , 2000, Nature Biotechnology.

[14]  M. Estelle,et al.  The axr6 mutants of Arabidopsis thaliana define a gene involved in auxin response and early development. , 2000, Development.

[15]  K. Schrick,et al.  FACKEL is a sterol C-14 reductase required for organized cell division and expansion in Arabidopsis embryogenesis. , 2000, Genes & development.

[16]  F. Carland,et al.  LOP1: a gene involved in auxin transport and vascular patterning in Arabidopsis. , 1996, Development.

[17]  S. Tabata,et al.  Compilation of all genes encoding bacterial two-component signal transducers in the genome of the cyanobacterium, Synechocystis sp. strain PCC 6803. , 1996, DNA research : an international journal for rapid publication of reports on genes and genomes.

[18]  T. Nelson,et al.  Genetic Regulation of Vascular Tissue Patterning in Arabidopsis , 1999, Plant Cell.

[19]  K. Shinozaki,et al.  A Transmembrane Hybrid-Type Histidine Kinase in Arabidopsis Functions as an Osmosensor , 1999, Plant Cell.

[20]  J Schultz,et al.  SMART, a simple modular architecture research tool: identification of signaling domains. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[21]  T. Steeves,et al.  Patterns in plant development: Subject index , 1972 .

[22]  J. Sambrook,et al.  Molecular Cloning: A Laboratory Manual , 2001 .

[23]  J. W. Wilson,et al.  The position of regenerating cambia: auxin/sucrose ratio and the gradient induction hypothesis , 1978, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[24]  G. Shaulsky,et al.  SDF-2 Induction of Terminal Differentiation in Dictyostelium discoideum Is Mediated by the Membrane-Spanning Sensor Kinase DhkA , 1999, Molecular and Cellular Biology.

[25]  G. Shaulsky,et al.  A two‐component histidine kinase gene that functions in Dictyostelium development. , 1996, The EMBO journal.

[26]  R. Aloni,et al.  Differentiation of Vascular Tissues , 1987 .

[27]  K. Esau.  Anatomy of seed plants , 1960 .

[28]  C. Dean,et al.  Embryonic origin of the Arabidopsis primary root and root meristem initials , 1994 .

[29]  T. Kakimoto.  CKI1, a Histidine Kinase Homolog Implicated in Cytokinin Signal Transduction , 1996, Science.

[30]  G. Jürgens,et al.  Coordinated polar localization of auxin efflux carrier PIN1 by GNOM ARF GEF. , 1999, Science.

[31]  K. Shinozaki,et al.  Two-component systems in plant signal transduction. , 2000, Trends in plant science.

[32]  F. Ausubel,et al.  A procedure for mapping Arabidopsis mutations using co-dominant ecotype-specific PCR-based markers. , 1993, The Plant journal : for cell and molecular biology.

[33]  J. Doyle,et al.  Isolation of plant DNA from fresh tissue , 1990 .

[34]  Eugen C. Buehler,et al.  Sequence and analysis of chromosome 2 of the plant Arabidopsis thaliana , 1999, Nature.

[35]  P. Benfey,et al.  Mutations affecting the radial organisation of the Arabidopsis root display specific defects throughout the embryonic axis , 1995 .