title: Isolation and functional analyses of a putative floral homeotic C-function gene in a basal eudicot London plane tree (Platanus acerifolia).
abstract: The identification of mutants in model plant species has led to the isolation of the floral homeotic function genes that play crucial roles in flower organ specification. However, floral homeotic C-function genes are rarely studied in basal eudicots. Here, we report the isolation and characterization of the AGAMOUS (AG) orthologous gene (PaAG) from a basal eudicot London plane tree (Platanus acerifolia Willd). Phylogenetic analysis showed that PaAG belongs to the C- clade AG group of genes. PaAG was found to be expressed predominantly in the later developmental stages of male and female inflorescences. Ectopic expression of PaAG-1 in tobacco (Nicotiana tabacum) resulted in morphological alterations of the outer two flower whorls, as well as some defects in vegetative growth. Scanning electron micrographs (SEMs) confirmed homeotic sepal-to-carpel transformation in the transgenic plants. Protein interaction assays in yeast cells indicated that PaAG could interact directly with PaAP3 (a B-class MADS-box protein in P. acerifolia), and also PaSEP1 and PaSEP3 (E-class MADS-box proteins in P. acerifolia). This study performed the functional analysis of AG orthologous genes outside core eudicots and monocots. Our findings demonstrate a conserved functional role of AG homolog in London plane tree, which also represent a contribution towards understanding the molecular mechanisms of flower development in this monoecious tree species.
authors.affiliation: Key Laboratory of Horticultural Plant Biology, Ministry of Education, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, Hubei, PR China.
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Zhang
authors.forename: Zhineng
authors.initials: Z
authors.lastname: Li
authors.forename: Cong
authors.initials: C
authors.lastname: Guo
authors.forename: Guofeng
authors.initials: G
authors.lastname: Liu
authors.forename: Manzhu
authors.initials: M
authors.lastname: Bao
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D005801:Genes, Homeobox; D017343:Genes, Plant; D019684:Magnoliopsida / Q000145:classification / Q000235:genetics*; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana / Q000235:genetics