Transcriptome profiling of Lotus japonicus roots during arbuscular mycorrhiza development and comparison with that of nodulation.

To better understand the molecular responses of plants to arbuscular mycorrhizal (AM) fungi, we analyzed the differential gene expression patterns of Lotus japonicus, a model legume, with the aid of a large-scale cDNA macroarray. Experiments were carried out considering the effects of contaminating microorganisms in the soil inoculants. When the colonization by AM fungi, i.

Genetics of symbiosis in Lotus japonicus: recombinant inbred lines, comparative genetic maps, and map position of 35 symbiotic loci.

Development of molecular tools for the analysis of the plant genetic contribution to rhizobial and mycorrhizal symbiosis has provided major advances in our understanding of plant-microbe interactions, and several key symbiotic genes have been identified and characterized. In order to increase the efficiency of genetic analysis in the model legume Lotus japonicus, we present here a selection of improved genetic tools. The two genetic linkage maps previously developed from an interspecific cross between L.

Characterization of the Lotus japonicus symbiotic mutant lot1 that shows a reduced nodule number and distorted trichomes.

We isolated a recessive symbiotic mutant of Lotus japonicus that defines a genetic locus, LOT1 (for low nodulation and trichome distortion). The nodule number per plant of the mutant was about one-fifth of that of the wild type. The lot1 mutant showed a moderate dwarf phenotype and distorted trichomes, but its root hairs showed no apparent differences to those of the wild type.

Cloning and expression analysis of a MAPKKK gene and a novel nodulin gene of Lotus japonicus.

We isolated a cDNA encoding mitogen-activated protein kinase kinase kinase alpha, designated LjM3Kalpha, from Lotus japonicus, a model legume. The gene was expressed constitutively in roots, root nodules, and shoots. We also identified a novel nodulin gene, LjNUF, that shows specific expression in nodules.