Poster abstracts
Poster number 48 submitted by Anna H. N. Griffis
Medicago truncatula LINC complexes and their potential role in root symbioses
Anna Hare Newman Griffis (Department of Molecular Genetics and Center for RNA Biology, The Ohio State University, Columbus, OH, USA), Katherine Beigel (Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA), Myriam Charpentier (Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK), Giles E.D. Oldroyd (Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK), Iris Meier (Department of Molecular Genetics and Center for RNA Biology, The Ohio State University, Columbus, OH, USA)
Abstract:
Several crop plants’ productivity depends on root symbionts that provide the plants with vital nutrients. One of the most important events in symbiosis establishment is the initiation of interactions between plant roots and soil-dwelling microbes, including rhizobia and arbuscular mycorrhizal fungi (AMF). The role of nuclear migration in these processes has long been implied, but never definitively established. Recently, LINC complexes, consisting of SUN and KASH proteins, have been shown to be components of metazoan nuclear movement machinery. While SUN proteins are widely conserved, no animal KASH protein homologs exist in plants. Working in the model plant Arabidopsis, our lab recently discovered the first plant KASH proteins, which are involved in processes ranging from root hair and pollen tube nuclear movement to oomycete defense. However, Arabidopsis is a host to neither rhizobia nor to AMF. Therefore, to study the role of LINC complexes in nuclear movement during symbiosis establishment, we have adopted a reverse genetics approach in the model legume Medicago truncatula. We have identified 12 genes encoding putative Medicago LINC complex components via bioinformatic tools. Here, we will show subcellular localization data for these LINC complex candidates from transient expression assays in Nicotiana benthamiana. Further candidate validation by co-immunoprecipitation with appropriate putative binding partners (i.e. SUN-KASH interactions) will also be presented. Tnt1 retrotransposon insertion mutant lines have been obtained for 8 of the 12 putative LINC complex component genes. Results from phenotypic analyses performed on mutant lines, focusing on potential symbiosis and/or nuclear movement defects, will also be shown.
Keywords: symbiosis, Medicago, nuclear envelope