Max-Planck-Innovation GmbH
Amalienstr. 33
80799 Munich
Germany
Technology Offer
Full Crop Protection From Insect Pests by Expression
of Long Double-Stranded RNAs in Plastids
Phone: +49 (89) 29 09 19 - 0
Fax:
+49 (89) 29 09 19 - 99
[email protected]
www.max-planck-innovation.de
File no.: MI-0402-4919-MG
Contact:
Dr. Mareike Göritz
Tel.: 089 / 290919-32
[email protected]
Background
Transgenic plants expressing long double-stranded RNAs (dsRNAs) targeted against essential
insect pest genes are a promising concept in plant protection and may eventually replace
currently used insecticides. Transgenically produced dsRNAs of at least 60 bp in length are
efficiently taken up by herbivorous insect pests, processed into small interfering RNAs (siRNA),
and can trigger a lethal RNA interference (RNAi) response. However, despite a first successful
proof of concept, the insecticidal efficacy currently achievable by transgenically delivered RNAi
is still hampered due to the presence of an endogenous RNAi pathway in plants, which
significantly lowers the levels of dsRNAs with sufficient length needed to provide protection.
Technology
Scientists from the Max Planck Institute of Molecular Plant Physiology and the Max Planck
Institute of Chemical Ecology have recently developed a new technology overcoming this major
hurdle in exploiting transgenically delivered RNAi in plant protection from pests (Ref. 1). By
shifting the target of transgenesis from the nucleus to chloroplasts (which lack an RNAi
machinery), and selecting optimized dsRNA expression constructs, the scientists achieved a
dramatic increase in dsRNA expression levels of up to 0.4% of total cellular RNA.
Figure 1: Bioassay measuring damage
by Colorado potato beetle larvae on
detached leaves of wilde-type (left),
nuclear dsRNA-expressing (middle), and
transplastomically
dsRNA-expressing
(right) potato plants.
Strikingly, as exemplified by transplastomic potato plants producing dsRNAs targeted against
the β-actin gene of the Colorado potato beetle, such a dramatic increase in dsRNAs levels
induced up to 100% mortality of the herbivorous insect pest in only 5 days, resulting in full plant
protection with only minimal herbivorous damage (see Fig. 1).
Due to its exceptionally high insecticidal activity without negatively affecting plant growth and
tuber production, the new transplastomically delivered RNAi technology is a highly attractive
solution to efficiently control the Colorado potato beetle and other herbivorous “international
superpests”. This technology may efficiently overcome problems in the application of currently
available insecticides such as environmental pollution or the evolution of resistance. We are
currently seeking a partner who is interested in commercially exploiting and licensing this
technology.
Patent Information: A European priority application has been filed in December 2014
Literature: (1) Zhang, J. et al., Science, 2015, 347(6225):991-4.