Pathway-based analysis of anthocyanin diversity in diploid potato

PLoS One. 2021 Apr 29;16(4):e0250861. doi: 10.1371/journal.pone.0250861. eCollection 2021.

Abstract

Anthocyanin biosynthesis is one of the most studied pathways in plants due to the important ecological role played by these compounds and the potential health benefits of anthocyanin consumption. Given the interest in identifying new genetic factors underlying anthocyanin content we studied a diverse collection of diploid potatoes by combining a genome-wide association study and pathway-based analyses. By using an expanded SNP dataset, we identified candidate genes that had not been associated with anthocyanin variation in potatoes, namely a Myb transcription factor, a Leucoanthocyanidin dioxygenase gene and a vacuolar membrane protein. Importantly, a genomic region in chromosome 10 harbored the SNPs with strongest associations with anthocyanin content in GWAS. Some of these SNPs were associated with multiple anthocyanin compounds and therefore could underline the existence of pleiotropic genes or anthocyanin biosynthetic clusters. We identified multiple anthocyanin homologs in this genomic region, including four transcription factors and five enzymes that could be governing anthocyanin variation. For instance, a SNP linked to the phenylalanine ammonia-lyase gene, encoding the first enzyme in the phenylpropanoid biosynthetic pathway, was associated with all of the five anthocyanins measured. Finally, we combined a pathway analysis and GWAS of other agronomic traits to identify pathways related to anthocyanin biosynthesis in potatoes. We found that methionine metabolism and the production of sugars and hydroxycinnamic acids are genetically correlated to anthocyanin biosynthesis. The results contribute to the understanding of anthocyanins regulation in potatoes and can be used in future breeding programs focused on nutraceutical food.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anthocyanins / biosynthesis*
  • Biosynthetic Pathways*
  • Computational Biology / methods
  • Coumaric Acids / metabolism
  • Diploidy
  • Gene Expression Regulation, Plant
  • Genome-Wide Association Study / methods*
  • Methionine / metabolism
  • Phenylalanine Ammonia-Lyase / genetics
  • Plant Proteins / genetics
  • Polymorphism, Single Nucleotide*
  • Quantitative Trait Loci
  • Solanum tuberosum / genetics
  • Solanum tuberosum / metabolism*

Substances

  • Anthocyanins
  • Coumaric Acids
  • Plant Proteins
  • Methionine
  • Phenylalanine Ammonia-Lyase

Grants and funding

This study received support from the following sources: Colciencias (now Minciencias, https://minciencias.gov.co/) grant number 110171250437, awarded to TMV; the International Development Research Centre (IDRC) and Global Affairs Canada through the Canadian International Food Security Research Fund (CIFSRF), which funded the project San Nariño number 108125-002, received by TMV; and Convenio 566 of 2014 between Universidad Nacional de Colombia (https://unal.edu.co/) and Colciencias (now Minciencias, https://minciencias.gov.co/), received by FRF.