Expression profiling of auxin-treated Arabidopsis roots: toward a molecular analysis of lateral root emergence.

Treating Arabidopsis roots with exogenous auxin results in dramatic changes in cellular processes including de novo induction of lateral roots which later emerge through the overlying cells. Microarray experiments reveal approximately 80 genes that are substantially up-regulated in the root over the first 12 h following auxin treatment. We hypothesize that the observed increase in expression of pectate lyase family genes leads to degradation of the pectin-rich middle lamellae, allowing cells in the parent root to separate cleanly. Differences in the degree of pectin methylation in lateral and parent roots may explain why lateral roots are not degraded themselves.

[1]  J. Braam,et al.  Genome-wide identification of touch- and darkness-regulated Arabidopsis genes: a focus on calmodulin-like and XTH genes. , 2004, The New phytologist.

[2]  P. Zimmermann,et al.  GENEVESTIGATOR. Arabidopsis Microarray Database and Analysis Toolbox1[w] , 2004, Plant Physiology.

[3]  D. Shasha,et al.  A Gene Expression Map of the Arabidopsis Root , 2003, Science.

[4]  S. Rhee,et al.  Microspore Separation in the quartet 3 Mutants of Arabidopsis Is Impaired by a Defect in a Developmentally Regulated Polygalacturonase Required for Pollen Mother Cell Wall Degradation1 , 2003, Plant Physiology.

[5]  A. Benítez-Burraco,et al.  Cloning and characterization of two ripening-related strawberry (Fragaria x ananassa cv. Chandler) pectate lyase genes. , 2003, Journal of experimental botany.

[6]  T. Koshiba,et al.  The HAT2 gene, a member of the HD-Zip gene family, isolated as an auxin inducible gene by DNA microarray screening, affects auxin response in Arabidopsis. , 2002, The Plant journal : for cell and molecular biology.

[7]  G. Seymour,et al.  Pectate lyases, cell wall degradation and fruit softening. , 2002, Journal of experimental botany.

[8]  E. Lulai,et al.  Histological analysis of the maturation of native and wound periderm in potato (Solanum tuberosum L.) Tuber. , 2002, Annals of botany.

[9]  I. Sussex,et al.  FQR1, a Novel Primary Auxin-Response Gene, Encodes a Flavin Mononucleotide-Binding Quinone Reductase1 , 2002, Plant Physiology.

[10]  V. Valpuesta,et al.  Manipulation of Strawberry Fruit Softening by Antisense Expression of a Pectate Lyase Gene1 , 2002, Plant Physiology.

[11]  I. Connerton,et al.  A pectate lyase from Zinnia elegans is auxin inducible. , 2002, The Plant journal : for cell and molecular biology.

[12]  S. Patterson Cutting loose. Abscission and dehiscence in Arabidopsis. , 2001, Plant physiology.

[13]  M. Pfaffl,et al.  A new mathematical model for relative quantification in real-time RT-PCR. , 2001, Nucleic acids research.

[14]  D. Cosgrove,et al.  Altered expression of expansin modulates leaf growth and pedicel abscission in Arabidopsis thaliana. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[15]  J. Benen,et al.  Structure and function of pectic enzymes: virulence factors of plant pathogens. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[16]  S. Lindow,et al.  Contribution of Indole-3-Acetic Acid Production to the Epiphytic Fitness of Erwinia herbicola , 1998, Applied and Environmental Microbiology.

[17]  G. Coruzzi,et al.  Arabidopsis mutant analysis and gene regulation define a nonredundant role for glutamate dehydrogenase in nitrogen assimilation. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[18]  H. Nusbaum,et al.  Formation of lateral root meristems is a two-stage process. , 1995, Development.

[19]  D. Inzé,et al.  Superroot, a recessive mutation in Arabidopsis, confers auxin overproduction. , 1995, The Plant cell.

[20]  M. Hawes,et al.  Correlation of Pectin Methylesterase Activity in Root Caps of Pea with Root Border Cell Separation , 1994, Plant physiology.

[21]  R. W. Davis,et al.  The HAT4 gene of Arabidopsis encodes a developmental regulator. , 1993, Genes & development.

[22]  F. Cervone,et al.  Expression and localization of polygalacturonase during the outgrowth of lateral roots in Allium porrum L. , 1992, Planta.

[23]  C. Steeling CRYSTAL‐STRUCTURE OF RUTHENIUM RED AND STEREOCHEMISTRY OF ITS PECTIC STAIN , 1970 .

[24]  J. Roberts,et al.  Abscission, dehiscence, and other cell separation processes. , 2002, Annual review of plant biology.

[25]  H. Fukaki,et al.  Lateral root formation is blocked by a gain-of-function mutation in the SOLITARY-ROOT/IAA14 gene of Arabidopsis. , 2002, The Plant journal : for cell and molecular biology.

[26]  Y. Komeda,et al.  Cloning and characterization of an L1 layer-specific gene in Arabidopsis thaliana. , 1999, Plant & cell physiology.

[27]  A. Theologis,et al.  The PS-IAA4/5-like family of early auxin-inducible mRNAs in Arabidopsis thaliana. , 1995, Journal of molecular biology.

[28]  N. Carpita,et al.  Structural models of primary cell walls in flowering plants: consistency of molecular structure with the physical properties of the walls during growth. , 1993, The Plant journal : for cell and molecular biology.