Two Lotus japonicus symbiosis mutants impaired at distinct steps of arbuscule development

Groth, Martin, Kosuta, Sonja, Gutjahr, Caroline, Haage, Kristina, Hardel, Simone Liesel, Schaub, Miriam, Brachmann, Andreas , Sato, Shusei, Tabata, Satoshi, Findlay, Kim, Wang, Trevor L. and Parniske, Martin (2013): Two Lotus japonicus symbiosis mutants impaired at distinct steps of arbuscule development. In: The Plant Journal, Vol. 75, No. 1: pp. 117-129

Abstract

Arbuscular mycorrhiza (AM) fungi form nutrient-acquiring symbioses with the majority of higher plants. Nutrient exchange occurs via arbuscules, highly branched hyphal structures that are formed within root cortical cells. With a view to identifying host genes involved in AM development, we isolated Lotus japonicus AM-defective mutants via a microscopic screen of an ethyl methanesulfonate-mutagenized population. A standardized mapping procedure was developed that facilitated positioning of the defective loci on the genetic map of L. japonicus, and, in five cases, allowed identification of mutants of known symbiotic genes. Two additional mutants representing independent loci did not form mature arbuscules during symbiosis with two divergent AM fungal species, but exhibited signs of premature arbuscule arrest or senescence. Marker gene expression patterns indicated that the two mutants are affected in distinct steps of arbuscule development. Both mutants formed wild-type-like root nodules upon inoculation with Mesorhizobium loti, indicating that the mutated loci are essential during AM but not during root nodule symbiosis.

• Item Type: Journal article
• Form of publication: Publisher's Version
• Keywords: Arbuscule; mycorrhiza; symbiosis; genetic screen; Lotus japonicus; map-based cloning
• Faculties: Biology > Department Biology I
• Subjects: 500 Science > 570 Life sciences; biology
• Language: English