Biofortification of oilseed Brassica juncea with the anti-cancer compound glucoraphanin by suppressing GSL-ALK gene family.

Abstract

Glucosinolates are amino acids derived secondary metabolites, invariably present in Brassicales, which have huge health and agricultural benefits. Sulphoraphane, the breakdown product of glucosinolate glucoraphanin is known to posses anti-cancer properties. AOP (2-oxoglutarate-dependent dioxygenases) or GSL-ALK enzyme catalyzes the conversion of desirable glucoraphanin to deleterious gluconapin and progoitrin, which are present in very high amounts in most of the cultivable Brassica species including Brassica juncea. In this study we showed that B. juncea encodes four functional homologs of GSL-ALK gene and constitutive silencing of GSL-ALK homologs resulted in accumulation of glucoraphanin up to 43.11 μmoles g(-1) DW in the seeds with a concomitant reduction in the anti-nutritional glucosinolates. Glucoraphanin content was found remarkably high in leaves as well as sprouts of the transgenic lines. Transcript quantification of high glucoraphanin lines confirmed significant down-regulation of GSL-ALK homologs. Growth and other seed quality parameters of the transgenic lines did not show drastic difference, compared to the untransformed control. High glucoraphanin lines also showed higher resistance towards stem rot pathogen Sclerotinia sclerotiorum. Our results suggest that metabolic engineering of GSL-ALK has huge potential for enriching glucoraphanin content, and improve the oil quality and vegetable value of Brassica crops.

• Authors: Rehna Augustine, Naveen C Bisht
• Journal: Scientific reports (Sci Rep) Vol. 5 Pg. 18005 (Dec 10 2015) ISSN: 2045-2322 [Electronic] England
• PMID: 26657321 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents, Phytogenic
• Glucosinolates
• Imidoesters
• Oximes
• Plant Extracts
• RNA, Small Interfering
• Sulfoxides
• Anaplastic Lymphoma Kinase
• Receptor Protein-Tyrosine Kinases
• glucoraphanin

Topics

• Anaplastic Lymphoma Kinase
• Antineoplastic Agents, Phytogenic (chemistry, pharmacology)
• Cloning, Molecular
• Disease Susceptibility
• Gene Knockdown Techniques
• Genetic Association Studies
• Glucosinolates (chemistry, pharmacology)
• Imidoesters (chemistry, pharmacology)
• Multigene Family
• Mustard Plant (chemistry)
• Oximes
• Phylogeny
• Plant Extracts (chemistry, pharmacology)
• Plants, Genetically Modified
• Quantitative Trait, Heritable
• RNA Interference
• RNA, Small Interfering (genetics)
• Receptor Protein-Tyrosine Kinases (genetics)
• Seeds (chemistry)
• Sequence Analysis, DNA
• Sulfoxides
• Transcription, Genetic