title: Distinct patterns of symbiosis-related gene expression in actinorhizal nodules from different plant families.
abstract: Phylogenetic analyses suggest that, among the members of the Eurosid I clade, nitrogen-fixing root nodule symbioses developed multiple times independently, four times with rhizobia and four times with the genus Frankia. In order to understand the degree of similarity between symbiotic systems of different phylogenetic subgroups, gene expression patterns were analyzed in root nodules of Datisca glomerata and compared with those in nodules of another actinorhizal plant, Alnus glutinosa, and with the expression patterns of homologous genes in legumes. In parallel, the phylogeny of actinorhizal plants was examined more closely. The results suggest that, although relationships between major groups are difficult to resolve using molecular phylogenetic analysis, the comparison of gene expression patterns can be used to inform evolutionary relationships. In this case, stronger similarities were found between legumes and intracellularly infected actinorhizal plants (Alnus) than between actinorhizal plants of two different phylogenetic subgroups (Alnus/Datisca).
authors.affiliation: Department of Molecular Biology, Agricultural University, Dreijenlaan 3, 6703 HA Wageningen, The Netherlands. kpawlow@gwdg.de
authors.forename: Katharina
authors.initials: K
authors.lastname: Pawlowski
authors.forename: Susan
authors.initials: S
authors.lastname: Swensen
authors.forename: Changhui
authors.initials: C
authors.lastname: Guan
authors.forename: Az-Eddine
authors.initials: AE
authors.lastname: Hadri
authors.forename: Alison M
authors.initials: AM
authors.lastname: Berry
authors.forename: Ton
authors.initials: T
authors.lastname: Bisseling
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D017931:DNA Primers; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics; D018517:Plant Roots; D010944:Plants / Q000145:classification / Q000235:genetics* / Q000382:microbiology; D017386:Sequence Homology, Amino Acid; D013559:Symbiosis
chemical_list: D017931:DNA Primers; D010940:Plant Proteins