title: Identification and validation of reference genes for accurate normalization of real-time quantitative PCR data in kiwifruit.
abstract: Identification and validation of reference genes are required for the normalization of qPCR data. We studied the expression stability produced by eight primer pairs amplifying four common genes used as references for normalization. Samples representing different tissues, organs and developmental stages in kiwifruit (Actinidia chinensis var. deliciosa (A. Chev.) A. Chev.) were used. A total of 117 kiwifruit samples were divided into five sample sets (mature leaves, axillary buds, stigmatic arms, fruit flesh and seeds). All samples were also analysed as a single set. The expression stability of the candidate primer pairs was tested using three algorithms (geNorm, NormFinder and BestKeeper). The minimum number of reference genes necessary for normalization was also determined. A unique primer pair was selected for amplifying the 18S rRNA gene. The primer pair selected for amplifying the ACTIN gene was different depending on the sample set. 18S 2 and ACT 2 were the candidate primer pairs selected for normalization in the three sample sets (mature leaves, fruit flesh and stigmatic arms). 18S 2 and ACT 3 were the primer pairs selected for normalization in axillary buds. No primer pair could be selected for use as the reference for the seed sample set. The analysis of all samples in a single set did not produce the selection of any stably expressing primer pair. Considering data previously reported in the literature, we validated the selected primer pairs amplifying the FLOWERING LOCUS T gene for use in the normalization of gene expression in kiwifruit.
authors.affiliation: Departamento de Fisiología Vegetal, Facultad de Farmacia, Universidad de Santiago, Campus Sur, 15872, Santiago de Compostela, Spain.
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Ferradás
authors.affiliation: Departamento de Biología Vegetal y Ciencia del Suelo, Facultad de Biología, Universidad de Vigo, 36310, Vigo, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Rey
authors.affiliation: Departamento de Biología Vegetal y Ciencia del Suelo, Facultad de Biología, Universidad de Vigo, 36310, Vigo, Spain.
authors.forename: Óscar
authors.initials: Ó
authors.lastname: Martínez
authors.affiliation: Departamento de Biología Vegetal y Ciencia del Suelo, Facultad de Biología, Universidad de Vigo, 36310, Vigo, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Rey
authors.affiliation: Departamento de Fisiología Vegetal, Facultad de Farmacia, Universidad de Santiago, Campus Sur, 15872, Santiago de Compostela, Spain. Electronic address: mvictoria.gonzalez@usc.es.
authors.forename: Ma Victoria
authors.initials: MV
authors.lastname: González
mesh_terms: D029042:Actinidia / Q000235:genetics / Q000378:metabolism*; D017343:Genes, Plant; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods / Q000592:standards; D018749:RNA, Plant / Q000096:biosynthesis* / Q000235:genetics; D012337:RNA, Ribosomal, 18S / Q000096:biosynthesis* / Q000235:genetics; D012015:Reference Standards; D014157:Transcription Factors / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D010940:Plant Proteins; D018749:RNA, Plant; D012337:RNA, Ribosomal, 18S; D014157:Transcription Factors
keywords: 18S rRNA; ACTIN; FLOWERING LOCUS T; Gene expression; Kiwifruit; Reference genes; qPCR