title: Sapogenin content variation in Medicago inter-specific hybrid derivatives highlights some aspects of saponin synthesis and control.
abstract: In the Medicago genus, saponins are a complex mixture of triterpene glycosides showing a broad spectrum of biological properties. Here we analyzed the variation in the sapogenin content and composition of inter-specific hybrid Medicago sativa × Medicago arborea derivatives to highlight the pattern of this variation in plant organs (leaves/roots) and the possible mechanisms underlying it. In Sativa Arborea Cross (SAC) leaves and roots, saponins and sapogenins were evaluated using chromatographic methods. Phenotypic correlations between sapogenin content and bio-agronomic traits were examined. Expression studies on β-amyrin synthase and four cytochromes P450 (CYPs) involved in sapogenin biosynthesis and sequence analysis of the key gene of the hemolytic sapogenin pathway (CYP716A12) were performed. Chromatographic analyses revealed a different pattern of among-family variation for hemolytic and nonhemolytic sapogenins and saponins and for the two organs/tissues. Different correlation patterns of gene expression in roots and leaves were found. Diachronic analysis revealed a relationship between sapogenin content and gene transcriptional levels in the early stages of the productive cycle. The results suggest that there are different control mechanisms acting on sapogenin biosynthesis for leaves and roots, which are discussed. A key role for medicagenic acid in the control of sapogenin content in both the tissues is proposed and discussed.
authors.affiliation: Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Centro di Ricerca per le Produzioni Foraggere e Lattiero-Casearie, viale Piacenza 29, 26900, Lodi, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Carelli
authors.affiliation: Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Centro di Ricerca per le Produzioni Foraggere e Lattiero-Casearie, viale Piacenza 29, 26900, Lodi, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Biazzi
authors.affiliation: Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Centro di Ricerca per le Produzioni Foraggere e Lattiero-Casearie, viale Piacenza 29, 26900, Lodi, Italy.
authors.forename: Aldo
authors.initials: A
authors.lastname: Tava
authors.affiliation: Parco Tecnologico Padano, via Einsten- Loc. Cascina Codazza, 26900, Lodi, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Losini
authors.affiliation: Parco Tecnologico Padano, via Einsten- Loc. Cascina Codazza, 26900, Lodi, Italy.
authors.forename: Pamela
authors.initials: P
authors.lastname: Abbruscato
authors.affiliation: Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Centro di Ricerca per le Produzioni Foraggere e Lattiero-Casearie, viale Piacenza 29, 26900, Lodi, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Depedro
authors.affiliation: Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Centro di Ricerca per le Produzioni Foraggere e Lattiero-Casearie, viale Piacenza 29, 26900, Lodi, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Scotti
mesh_terms: D001483:Base Sequence; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D019751:Intramolecular Transferases / Q000235:genetics* / Q000378:metabolism; D029902:Medicago / Q000235:genetics / Q000378:metabolism*; D000455:Medicago sativa / Q000235:genetics / Q000378:metabolism; D046913:Medicago truncatula / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009928:Organ Specificity; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D012502:Sapogenins / Q000378:metabolism*; D012503:Saponins / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D014315:Triterpenes / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D012502:Sapogenins; D012503:Saponins; D014315:Triterpenes; C005982:medicagenic acid; D003577:Cytochrome P-450 Enzyme System; D019751:Intramolecular Transferases; C039924:2,3-oxidosqualene-beta-amyrin-cyclase
keywords: Medicago arborea; Medicago sativa (alfalfa); cytochrome P450 expression; inter-specific cross; sapogenin synthesis; triterpene saponin