title: Novel candidate genesAuxRPandHsp90influence the chip color of potato tubers.
abstract: Potato (Solanum tuberosumL.) tubers exhibit significant variation in reducing sugar content directly after harvest, cold storage and reconditioning. Here, we performed QTL analysis for chip color, which is strongly influenced by reducing sugar content, in a diploid potato mapping population. Two QTL on chromosomes I and VI were detected for chip color after harvest and reconditioning. Only one region on chromosome VI was linked with cold-induced sweetening. Using the RT-PCR technique, we showed differential expression of theauxin-regulated protein(AuxRP) gene. TheAuxRPtranscript was presented in light chip color parental clone DG 97-952 and the RNA progeny of the bulk sample consisting of light chip color phenotypes after cold storage. This amplicon was absent in dark chip parental clone DG 08-26/39 and the RNA bulk sample of dark chip progeny. Genetic variation ofAuxRPexplained up to 16.6 and 15.2 % of the phenotypic variance after harvest and 3 months of storage at 4 °C, respectively. Using an alternative approach, the RDA-cDNA method was used to recognize 25 gene sequences, of which 11 could be assigned to potato chromosome VI. One of these genes,Heat-shock protein 90(Hsp90), demonstrated higher mRNA and protein expression in RT-qPCR and western blotting assays in the dark chip color progeny bulk sample compared with the light chip color progeny bulk sample. Our study, for the first time, suggests that theAuxRPandHsp90genes are novel candidate genes capable of influencing the chip color of potato tubers.
authors.affiliation: Plant Breeding and Acclimatization Institute, National Research Institute, Młochów, Platanowa 19, 05-831 Młochów, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Sołtys-Kalina
authors.affiliation: Plant Breeding and Acclimatization Institute, National Research Institute, Młochów, Platanowa 19, 05-831 Młochów, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Szajko
authors.affiliation: Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland.
authors.forename: Izabela
authors.initials: I
authors.lastname: Sierocka
authors.affiliation: Plant Breeding and Acclimatization Institute, National Research Institute, Młochów, Platanowa 19, 05-831 Młochów, Poland.
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Śliwka
authors.affiliation: Plant Breeding and Acclimatization Institute, National Research Institute, Młochów, Platanowa 19, 05-831 Młochów, Poland.
authors.forename: Danuta
authors.initials: D
authors.lastname: Strzelczyk-Żyta
authors.affiliation: Plant Breeding and Acclimatization Institute, National Research Institute, Młochów, Platanowa 19, 05-831 Młochów, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Wasilewicz-Flis
authors.affiliation: Plant Breeding and Acclimatization Institute, National Research Institute, Młochów, Platanowa 19, 05-831 Młochów, Poland.
authors.forename: Henryka
authors.initials: H
authors.lastname: Jakuczun
authors.affiliation: Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland.
authors.forename: Zofia
authors.initials: Z
authors.lastname: Szweykowska-Kulinska
authors.affiliation: Plant Breeding and Acclimatization Institute, National Research Institute, Młochów, Platanowa 19, 05-831 Młochów, Poland.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Marczewski
keywords: Auxin-regulated protein (AuxRP) gene; DArT markers; Heat-shock protein 90 (Hsp90) gene; Quantitative trait loci; Reducing sugar content; Solanum tuberosum