The role of agrobacterium-mediated and other gene-transfer technologies in cannabis research and product development

Abstract

Cannabis sativa is a multi-use crop valued for its pharmacological properties and as a fibre and seed crop. Biotechnological applications toward Cannabis research and product development are still in their early stages. An important feature of biotechnology is the collection of gene transfer technologies that are used to introduce genetic material into host organisms. Agrobacterium tumefaciens and A. Rhizogenes represent the most common vectors to transfer genetic material into plant cells. Stable and transient gene expression can be achieved using A. Tumefaciens while A. Rhizogenes generates stable transformed hairy roots. Cannabis is amenable to genetic transformation using both Agrobacterium vectors, however the plant is recalcitrant to regeneration, impeding the recovery of transgenic Cannabis plants. Despite this shortcoming, the cannabi- noid pathway is currently attracting considerable attention from the biotechnology community. Gene transfer technologies have assisted with the characterization of the cannabinoid pathway leading to the synthesis of THCA, the psychoactive compound that is highly valued as a therapeutic. Elucidation of the cannabinoid pathway has led to its metabolic engineering in heterologous hosts. The yeast Pichia pastoris has proven to be a particularly suitable host for the production of cannabinoids. Recently, biotechnology companies have emerged that anticipate commercializing cannabinoid-based drugs in yeast and tobacco and to produce hemp cultivars with the cannabinoid pathway down-regulated or completely knocked out.