title: Central role of FaGAMYB in the transition of the strawberry receptacle from development to ripening.
abstract: The receptacle of the strawberry (Fragaria × ananassa) fruit accounts for the main properties of the ripe fruit for human consumption. As it ripens, it undergoes changes similar to other fruits in sugar : acid ratio, volatile production and cell wall softening. However, the main regulators of this process have not yet been reported. The white stage marks the initiation of the ripening process, and we had previously reported a peak of expression for a FaGAMYB gene. Transient silencing of FaGAMYB using RNAi and further determination of changes in global gene expression by RNAseq, and composition of primary and secondary metabolites have been used to investigate the role played by this gene during the development of the receptacle. Down-regulation of FaGAMYB caused an arrest in the ripening of the receptacle and inhibited colour formation. Consistent with this, several transcription factors associated with the regulation of flavonoid biosynthetic pathway showed altered expression. FaGAMYB silencing also caused a reduction of ABA biosynthesis and sucrose content. Interestingly, exogenous ABA application to the RNAI-transformed receptacle reversed most defects caused by FaGAMYB down-regulation. The study assigns a key regulatory role to FaGAMYB in the initiation of strawberry receptacle ripening and acting upstream of the known regulator ABA.
authors.affiliation: Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea (IHSM), Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Málaga, Spain.
authors.forename: José G
authors.initials: JG
authors.lastname: Vallarino
authors.affiliation: Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea (IHSM), Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Málaga, Spain.
authors.forename: Sonia
authors.initials: S
authors.lastname: Osorio
authors.affiliation: Department of Horticulture, Virginia Tech, 24060, Blacksburg, VA, USA.
authors.forename: Aureliano
authors.initials: A
authors.lastname: Bombarely
authors.affiliation: Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea (IHSM), Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Málaga, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Casañal
authors.affiliation: Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea (IHSM), Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Málaga, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Cruz-Rus
authors.affiliation: Instituto Andaluz de Investigación y Formación Agraria y Pesquera (IFAPA), Centro de Churriana, Málaga, Spain.
authors.forename: José F
authors.initials: JF
authors.lastname: Sánchez-Sevilla
authors.affiliation: Instituto Andaluz de Investigación y Formación Agraria y Pesquera (IFAPA), Centro de Churriana, Málaga, Spain.
authors.forename: Iraida
authors.initials: I
authors.lastname: Amaya
authors.affiliation: Max-Planck Institute of Molecular Plant Physiology, 14476, Postdam-Golm, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Giavalisco
authors.affiliation: Max-Planck Institute of Molecular Plant Physiology, 14476, Postdam-Golm, Germany.
authors.forename: Alisdair R
authors.initials: AR
authors.lastname: Fernie
authors.affiliation: Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea (IHSM), Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Málaga, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Botella
authors.affiliation: Departamento de Biología Molecular y Bioquímica, Instituto de Hortofruticultura Subtropical y Mediterranea (IHSM), Universidad de Málaga-Consejo Superior de Investigaciones Científicas, Málaga, Spain.
authors.forename: Victoriano
authors.initials: V
authors.lastname: Valpuesta
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D003433:Crosses, Genetic; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D031985:Fragaria / Q000235:genetics / Q000254:growth & development* / Q000502:physiology; D005638:Fruit / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005875:Gibberellins / Q000494:pharmacology; D008954:Models, Biological; D010940:Plant Proteins / Q000378:metabolism*; D034622:RNA Interference / Q000187:drug effects; D060888:Real-Time Polymerase Chain Reaction; D064210:Secondary Metabolism / Q000187:drug effects; D015854:Up-Regulation / Q000235:genetics
chemical_list: D005875:Gibberellins; D010940:Plant Proteins; D000040:Abscisic Acid
keywords: ABA; FaGAMYB; Fragaria × ananassa; GA; fruit ripening; strawberry receptacle; sucrose