Dissecting the genetic control of root and leaf tissue-specific anthocyanin pigmentation in carrot (Daucus carota L.)

• Autores: Bannoud, Florencia; Ellison, Shelby L.; Paolinelli, Marcos; Horejsi, Thomas; Senalik, Douglas A.; Fanzone, Martín Leandro; Iorizzo, Massimo; Simon, Philipp W.; Cavagnaro, Pablo
• Año de publicación: 2019
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Theoretical and Applied Genetics 132 (9) : 2485–2507 (September 2019)
• Materia: Zanahoria; Daucus Carota; Variedades; Genética; Antocianinas; Pigmentación; Carrots; Varieties; Genetics; Anthocyanins; Pigmentation; Zanahoria Púrpura
• Institución: Instituto Nacional de Tecnología Agropecuaria

Purple carrots can accumulate large quantities of anthocyanins in their root tissues, as well as in other plant parts. This work investigated the genetic control underlying tissue-specific anthocyanin pigmentation in the carrot root phloem and xylem, and in leaf petioles. Inheritance of anthocyanin pigmentation in these three tissues was first studied in segregating F2 and F4 populations, followed by QTL mapping of phloem and xylem anthocyanin pigments (independently) onto two genotyping by sequencing-based linkage maps, to reveal two regions in chromosome 3, namely P1 and P3, controlling pigmentation in these three tissues. Both P1 and P3 condition pigmentation in the phloem, with P3 also conditioning pigmentation in the xylem and petioles. By means of linkage mapping, phylogenetic analysis, and comparative transcriptome (RNA-Seq) analysis among carrot roots with differing purple pigmentation phenotypes, we identified candidate genes conditioning pigmentation in the phloem, the main tissue influencing total anthocyanin levels in the root. Among them, a MYB transcription factor, DcMYB7, and two cytochrome CYP450 genes with putative flavone synthase activity were identified as candidates regulating both the presence/absence of pigmentation and the concentration of anthocyanins in the root phloem. Concomitant expression patterns of DcMYB7 and eight anthocyanin structural genes were found, suggesting that DcMYB7 regulates transcription levels in the latter. Another MYB, DcMYB6, was upregulated in specific purple-rooted samples, suggesting a genotype-specific regulatory activity for this gene. These data contribute to the understanding of anthocyanin regulation in the carrot root at a tissue-specific level and maybe instrumental for improving carrot nutritional value.
EEA Mendoza
Fil: Bannoud, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Ellison, Shelby. University of Wisconsin. Department of Horticulture; Estados Unidos. United States Department of Agriculture–Agricultural Research Service. Vegetable Crops Research Unit; Estados Unidos
Fil: Paolinelli, Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; Argentina
Fil: Horejsi, Thomas. Department of Agriculture–Agricultural Research Service. Vegetable Crops Research Unit; Estados Unidos
Fil: Senalik, Douglas A. United States Department of Agriculture–Agricultural Research Service. Vegetable Crops Research Unit; Estados Unidos
Fil: Fanzone, Martí­n Leandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; Argentina
Fil: Iorizzo, Massimo. North Carolina State University. Plants for Human Health Institute; Estados Unidos. North Carolina State University. Department of Horticultural Science; Estados Unidos
Fil: Simon, Philipp. University of Wisconsin. Department of Horticulture; Estados Unidos. United States Department of Agriculture–Agricultural Research Service. Vegetable Crops Research Unit; Estados Unidos
Fil: Cavagnaro, Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Consulta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Horticultura; Argentina.