Transcriptomic evidence for the control of soybean root isoflavonoid content by regulation of overlapping phenylpropanoid pathways

BMC Genomics

Research Article

Mehran Dastmalchi¹  Ryan S. Austin¹  Sangeeta Dhaubhadel¹  Jaeju Yu²  Patrick Chapman² 

[1] Department of Biology, University of Western Ontario, London, ON, Canada;London Research and Development Centre, Agriculture and Agri-Food Canada, 1391 Sandford Street, N5V 4T3, London, ON, Canada;London Research and Development Centre, Agriculture and Agri-Food Canada, 1391 Sandford Street, N5V 4T3, London, ON, Canada;

关键词: Soybean;    Secondary metabolism;    Phenylpropanoid;    Isoflavonoid;    Root;    Transcriptome;    RNA sequencing;   

DOI  :  10.1186/s12864-016-3463-y

 received in 2016-08-24, accepted in 2016-12-22,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundIsoflavonoids are a class of specialized metabolites found predominantly in legumes. They play a role in signaling for symbiosis with nitrogen-fixing bacteria and inhibiting pathogen infection.ResultsA transcriptomic approach using soybean cultivars with high (Conrad and AC Colombe) and low (AC Glengarry and Pagoda) root isoflavonoid content was used to find elements that underlie this variation. Two genes, encoding the flavonoid-metabolizing enzymes, flavonoid 3′-hydroxylase (GmF3′H) and dihydroflavonol 4-reductase (GmDFR), had lower expression levels in high isoflavonoid cultivars. These enzymes compete with isoflavonoid biosynthetic enzymes for the important branch-point substrate naringenin and its derivatives. Differentially expressed genes, between the two sets of cultivars, encode transcription factors, transporters and enzymatic families of interest, such as oxidoreductases, hydrolases and transferases. In addition, genes annotated with stress and disease response were upregulated in high isoflavonoid cultivars.ConclusionsCoordinated regulation of genes involved in flavonoid metabolism could redirect flux into the isoflavonoid branch of the phenylpropanoid pathway, by reducing competition for the flavanone substrate. These candidate genes could help identify mechanisms to overcome the endogenous bottleneck to isoflavonoid production, facilitate biosynthesis in heterologous systems, and enhance crop resistance against pathogenic infections.

【 授权许可】

CC BY   
© The Author(s). 2017