title: VviAPRT3andVviFSEX: Two Genes Involved in Sex Specification Able to Distinguish Different Flower Types inVitis.
abstract: Vitis vinifera viniferais a hermaphrodite subspecies, while its ancestor,Vitis vinifera sylvestris, is dioecious. We have identified two genes that together allow the discrimination between male, female and hermaphroditeVitisplants. The sex locus region on chromosome 2 was screened resulting in the discovery of a new gene,VviFSEX. The same screening revealed another gene,VviAPRT3, located in the sex region, that be used as a sex marker. Both genes are good candidates to be involved in flower sex differentiation in grapevine. To assess their role in sex specification, spatial and temporal expression analysis was performed. The expression ofVviFSEXis detected in petals, stamens and carpel primordia of all flower types, making its putative function unclear; however, female plants display a single allele for this gene, while male and hermaphrodites display two alleles. On the other hand, the specific expression ofVviAPRT3in the carpel primordial of male plants suggests a possible role in the abortion of pistil structures. We propose a model to explain the carpel abortion in male flowers and the absence of stamen viability in female flowers. In addition, this work reinforces the presence of a sex locus onVitischromosome 2.
authors.affiliation: Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa Lisboa, Portugal.
authors.forename: João L
authors.initials: JL
authors.lastname: Coito
authors.affiliation: Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa Lisboa, Portugal.
authors.forename: Miguel J N
authors.initials: MJ
authors.lastname: Ramos
authors.affiliation: Instituto Nacional de Investigação Agrária e VeterináriaTorres Vedras, Portugal; Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de LisboaOeiras, Portugal.
authors.forename: Jorge
authors.initials: J
authors.lastname: Cunha
authors.affiliation: Biosystems and Integrative Sciences Institute, Plant Functional Biology Centre, University of Minho Braga, Portugal.
authors.forename: Helena G
authors.initials: HG
authors.lastname: Silva
authors.affiliation: Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa Lisboa, Portugal.
authors.forename: Sara
authors.initials: S
authors.lastname: Amâncio
authors.affiliation: Biosystems and Integrative Sciences Institute, Plant Functional Biology Centre, University of Minho Braga, Portugal.
authors.forename: Maria M R
authors.initials: MM
authors.lastname: Costa
authors.affiliation: Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa Lisboa, Portugal.
authors.forename: Margarida
authors.initials: M
authors.lastname: Rocheta
keywords: Vitis; dioecious; flower; gene marker; hermaphrodite; sex