A bicistronic transgene system for genetic modification of Parthenium argentatum

Authors: Ponciano, Grisel; DONG, NIU - University Of Nevada; Chen, Grace; McMahan, Colleen

Submitted to: Plant Biotechnology Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/14/2018
Publication Date: 2/22/2018
Citation: Ponciano, G.P., Dong, N., Chen, G.Q., McMahan, C.M. 2018. A bicistronic transgene system for genetic modification of Parthenium argentatum. Plant Biotechnology Reports. 12(2):149-155. https://doi.org/10.1007/s11816-018-0478-7.
DOI: https://doi.org/10.1007/s11816-018-0478-7

Interpretive Summary: Genetic improvement of rubber yield for Parthenium argentatum (guayule) may lead to faster improvements than by conventional or advanced breeding. It is well-known that rubber biosynthesis in guayule increases during cold stress. In this study, high expression of two genes important for rubber biosynthesis was achieved using cold-inducible technology. In the laboratory, higher rubber content (but not higher resin content) was found.

Technical Abstract: Parthenium argentatum (guayule) was transformed with a bicistronic transgene containing a viral 2A cleavage sequence. The transgene includes the coding sequences of two key enzymes of the mevalonate pathway, 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) and farnesyl pyrophosphate synthase (FPPS), involved in rubber biosynthesis. The viral 2A peptide sequence located between the two transgenes allowed for their co-expression via the Arabidopsis CBF2 (C-Binding repeat Factor 2) cold-inducible promoter. We identified three independent transgenic lines expressing the bicistronic transgenes upon cold treatment and examined the rubber content in the in vitro guayule plants.