Short- and long-distance control of root development by LjHAR1 during the juvenile stage of Lotus japonicus

J Plant Physiol. 2007 Apr;164(4):452-9. doi: 10.1016/j.jplph.2006.03.006. Epub 2006 May 9.


The autoregulation of nodulation (AON) is a universal mechanism to legumes to control the extent of nodulation via a systemic circuit and if genetically altered, as in the Lotus japonicus har1-1 mutant, leads to hypernodulation and aberrant root development. Increased nodulation of har1-1 is associated with pleiotropic effects both in the absence and presence of the symbiosis. We used two different grafting techniques to investigate the control of the non-symbiotic retarded root growth phenotype of har1-1, and demonstrate that altered root growth in the non-symbiotic condition is controlled by the genotype of both the shoot and the root. Based on these results and on the Gresshoff and Delves [Plant genetic approaches to symbiotic nodulation and nitrogen fixation in legumes. Plant Gene Res 1986;3:159-206] AON model, we propose an advanced working model for control of root development by LjHAR1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Genes, Plant*
  • Genotype
  • Homeostasis
  • Lotus / genetics*
  • Lotus / growth & development*
  • Lotus / metabolism
  • Models, Biological
  • Mutation
  • Nitrogen Fixation
  • Phenotype
  • Plant Roots / growth & development
  • Plant Roots / metabolism
  • Protein Kinases / genetics
  • Protein Kinases / metabolism
  • Root Nodules, Plant / growth & development
  • Root Nodules, Plant / metabolism
  • Signal Transduction
  • Symbiosis


  • Protein Kinases