Facultad de Ciencias Agrarias, Universidad Nacional de Colombia, Sede Bogotá, Bogotá, Colombia.
Departamento de Biología, Facultad de Ciencias, Universidad Nacional de Colombia, Sede Bogotá, Bogotá, Colombia.
PLoS One. 2021 Apr 29;16(4):e0250861. doi: 10.1371/journal.pone.0250861. eCollection 2021.
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.
花色素苷生物合成是植物中研究最多的途径之一，因为这些化合物在生态中起着重要作用，而花色素苷的消费也具有潜在的健康益处。鉴于人们对鉴定花色素苷含量的新遗传因素感兴趣，我们通过结合全基因组关联研究和基于途径的分析，研究了一个多样化的二倍体马铃薯群体。通过使用扩展的 SNP 数据集，我们鉴定出了一些尚未与马铃薯中花色素苷变异相关的候选基因，即一个 Myb 转录因子、一个 Leucoanthocyanidin dioxygenase 基因和一个液泡膜蛋白。重要的是，10 号染色体上的一个基因组区域包含了与 GWAS 中花色素苷含量最强相关的 SNP。其中一些 SNP 与多种花色素苷有关，因此可以强调存在多效基因或花色素苷生物合成簇。在这个基因组区域中，我们鉴定了多个花色素苷同源物，包括四个转录因子和五个可以控制花色素苷变异的酶。例如，与苯丙氨酸解氨酶基因（编码苯丙烷生物合成途径中的第一个酶）相关的 SNP 与测量的五种花色素苷都有关联。最后，我们结合了途径分析和其他农艺性状的 GWAS，以鉴定与马铃薯中花色素苷生物合成相关的途径。我们发现，蛋氨酸代谢以及糖和羟基肉桂酸的产生与花色素苷生物合成在遗传上是相关的。研究结果有助于了解马铃薯中花色素苷的调控机制，并可用于未来以营养食品为重点的育种计划。
