title: Expression pattern of two paralogs of the PI/GLO-like locus during Orchis italica (Orchidaceae, Orchidinae) flower development.
abstract: The class B MADS-box genes belong to two distinct functional groups: the AP3/DEF-like and the PI/GLO-like sub-families. In orchids, AP3/DEF-like genes are present in four copies, each with a different role in floral organ formation, which is described in the "orchid code" model. Interestingly, the orchid PI/GLO-like genes are present in two copies in Orchidinae, whereas they are described as single copy in the other orchid lineages. The two PI/GLO-like paralogs have site-specific different selective constraints; in addition, they show relaxation of purifying selection when compared to the single-copy lineages. In this study, we present a comparative analysis of the expression patterns of the two PI/GLO-like paralogs, OrcPI and OrcPI2, in floral tissues of Orchis italica in different developmental stages using real-time PCR. The two genes show similar expression profiles in the tissue examined, with differences detectable between immature and mature inflorescence. In all cases, OrcPI2 is expressed at a higher level than OrcPI. Real-time PCR results reveal that the co-expression of the two duplicated loci could have a fully or partially redundant function. The possible evolutionary fate of OrcPI and OrcPI2 is discussed as well as their involvement in ovary development.
authors: Department of Biological Sciences, University of Naples Federico II, via Mezzocannone 8, 80134 Naples, Italy.
authors: Marinella
authors: M
authors: Salemme
authors: Maria
authors: M
authors: Sica
authors: Luciano
authors: L
authors: Gaudio
authors: Serena
authors: S
authors: Aceto
mesh_terms: D035264:Flowers / Q000235:genetics / Q000254:growth & development*; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics*; D029595:Orchidaceae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics*
chemical_list: D018398:Homeodomain Proteins; D010940:Plant Proteins