title: Anthocyanin Accumulation in Muscadine Berry Skins Is Influenced by the Expression of the MYB Transcription Factors, MybA1, and MYBCS1.
abstract: The skin color of grape berry is very important in the wine industry. The red color results from the synthesis and accumulation of anthocyanins, which is regulated by transcription factors belonging to the MYB family. The transcription factors that activate the anthocyanin biosynthetic genes have been isolated in model plants. However, the genetic basis of color variation is species-specific and its understanding is relevant in many crop species. This study reports the isolation ofMybA1, andMYBCS-1genes from muscadine grapes for the first time. They are designated asVrMybA1(GenBank Accession No. KJ513437), andVrMYBCS1(VrMYB5a) (GenBank Accession No. KJ513438). The findings in this study indicate that, the deducedVrMybA1andVrMYBCS1protein structures share extensive sequence similarity with previously characterized plant MYBs, while phylogenetic analysis confirms that they are members of the plant MYB super-family. The expressions ofMybA1, andMYBCS1(VrMYB5a) gene sequences were investigated by quantitative real-time PCR using in vitro cell cultures, and berry skin samples at different developmental stages. Results showed thatMybA1, andMYBCS1genes were up-regulated in the veràison and physiologically mature red berry skins during fruit development, as well as in in vitro red cell cultures. This study also found that in ripening berries, the transcription ofVrMybA1, andVrMYBCS1in the berry skin was positively correlated with anthocyanin accumulation. Therefore, the upregulation ofVrMybA1, andVrMYBCS1results in the accumulation and regulation of anthocyanin biosynthesis in berry development of muscadine grapes. This work greatly enhances the understanding of anthocyanin biosynthesis in muscadine grapes and will facilitate future genetic modification of the antioxidants inV. rotundifolia.
authors.affiliation: Center for Viticulture and Small Fruit Research, College of Agriculture and Food Science, Florida A & M University, 6505 Mahan Drive, Tallahassee, FL 32317, USA. lillian.oglesby@gmail.com.
authors.forename: Lillian
authors.initials: L
authors.lastname: Oglesby
authors.affiliation: Center for Viticulture and Small Fruit Research, College of Agriculture and Food Science, Florida A & M University, 6505 Mahan Drive, Tallahassee, FL 32317, USA. anthony.ananga@gmail.com.|Food Science Program, College of Agriculture and Food Sciences, Florida A & M University, Tallahassee, FL 32307, USA. anthony.ananga@gmail.com.
authors.forename: Anthony
authors.initials: A
authors.lastname: Ananga
authors.affiliation: Center for Viticulture and Small Fruit Research, College of Agriculture and Food Science, Florida A & M University, 6505 Mahan Drive, Tallahassee, FL 32317, USA. jamesobuya@yahoo.com.
authors.forename: James
authors.initials: J
authors.lastname: Obuya
authors.affiliation: Faculties of Agriculture and Veterinary Medicine, University of Nairobi, P.O. Box 29053, Nairobi 00625, Kenya. jochieng@uonbi.ac.ke.
authors.forename: Joel
authors.initials: J
authors.lastname: Ochieng
authors.affiliation: Department of Biological and Environmental Sciences, Alabama A & M University, 4900 Meridian Street, Normal, AL 35762, USA. ecebert@gmail.com.
authors.forename: Ernst
authors.initials: E
authors.lastname: Cebert
authors.affiliation: Center for Viticulture and Small Fruit Research, College of Agriculture and Food Science, Florida A & M University, 6505 Mahan Drive, Tallahassee, FL 32317, USA. violeta.tsolova@famu.edu.
authors.forename: Violeta
authors.initials: V
authors.lastname: Tsolova
keywords: MYB gene; MYBCS1; MybA1; anthocyanins; antioxidants; muscadine grapes; pigments