Tag Archives: double-stranded RNA (dsRNA)

Systemic gene silencing in crops with engineered nanocomplexes

Ultimately, the researchers are working on ways to make agriculture more sustainable but, in the meantime, there’s this June 7, 2024 news item on ScienceDaily describing this work,

Gene silencing in plants has faced significant challenges, primarily due to the difficulty of transporting RNA molecules across plant cell membranes and achieving systemic effects. Traditional genetic engineering methods are time-consuming and often limited by plant genotype. Due to these challenges, there is a pressing need for innovative solutions to facilitate efficient gene silencing and enhance crop productivity.

A June 7, 2024 news release, from Nanjing Agricultural University The Academy of Science (publisher of Horticulture Research), on EurekAlert, which originated the news item, goes on to describe the challenges and the proposed solution, Note: Links have been removed,

Gene silencing in plants has faced significant challenges, primarily due to the difficulty of transporting RNA molecules across plant cell membranes and achieving systemic effects. Traditional genetic engineering methods are time-consuming and often limited by plant genotype. Due to these challenges, there is a pressing need for innovative solutions to facilitate efficient gene silencing and enhance crop productivity.

Researchers from the University of Connecticut and Oak Ridge National Laboratory have developed an innovative method using cationized bovine serum albumin (cBSA) and double-stranded RNA (dsRNA) nanocomplexes to achieve effective systemic gene silencing in plants. Published (DOI: 10.1093/hr/uhae045) in Horticulture Research on February 22, 2024, this study demonstrates the potential of these nanocomplexes to overcome the limitations of traditional RNA delivery methods, offering a new tool for plant biotechnology.

The study presents the development of cBSA/dsRNA nanocomplexes for systemic gene silencing in tobacco and poplar plants. By modifying bovine serum albumin to carry a positive charge, researchers created nanocomplexes that bind dsRNA molecules, facilitating their transport and systemic gene silencing. Experiments demonstrated successful silencing of the DR5-GUS and 35S-GUS genes, achieving significant reductions in gene expression. This technology proved effective in delivering RNA molecules across plant cell membranes, overcoming the negative charge barrier of naked RNA applications. Offering a convenient, fast, and non-transgenic approach, this method holds promise for gene function characterization, crop improvement, and large-scale agricultural applications due to its scalability and cost-effectiveness.

Dr. Yi Li, a lead researcher on the project, stated, “The development of cBSA/dsRNA nanocomplexes represents a significant advancement in plant biotechnology. This technology not only facilitates efficient gene silencing but also offers a practical and scalable solution for improving crop productivity. We believe this method will pave the way for new applications in gene editing and agricultural research.”

The implications of this research are vast, offering a potential solution for transient gene silencing in field-grown crops, including orchard trees. This technology could enhance crop productivity by targeting genes that influence drought tolerance, fruit development, and stress resistance, all without the need for genetic modification. The scalable and inexpensive nature of this method could make it a game-changer for sustainable agriculture.

The research and the journal where it is published both have interesting pedigrees. From the June 7, 2024 news release,

Funding information

This work was supported by the USDA National Institute of Food and Agriculture SCRI (grant no. 2015-70016-23027) and the Connecticut-Storrs Agriculture Experimental Station.

About Horticulture Research

Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2022. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.

You can add the UK to the US/China mix since the website hosting Horticulture Research is Oxford Academic,

Oxford Academic is Oxford University Press’s academic research platform, providing access to over 50,000 books and 500 journals

Finally, here’s a link to and a citation for the paper,

Engineered dsRNA–protein nanoparticles for effective systemic gene silencing in plants by Huayu Sun, Ankarao Kalluri, Dan Tang, Jingwen Ding, Longmei Zhai, Xianbin Gu, Yanjun Li, Huseyin Yer, Xiaohan Yang, Gerald A Tuskan, Zhanao Deng, Frederick G Gmitter Jr, Hui Duan, Challa Kumar, Yi Li. Horticulture Research, Volume 11, Issue 4, April 2024, uhae045, DOI: https://doi.org/10.1093/hr/uhae045
Published online: 22 February 2024

This paper is open access.

Clay nanosheets and world food security

This is some interesting agricultural research from Australia. From a Jan. 11, 2017 news item on phys.org,

A University of Queensland team has made a discovery that could help conquer the greatest threat to global food security – pests and diseases in plants.

Research leader Professor Neena Mitter said BioClay – an environmentally sustainable alternative to chemicals and pesticides – could be a game-changer for crop protection.

“In agriculture, the need for new control agents grows each year, driven by demand for greater production, the effects of climate change, community and regulatory demands, and toxicity and pesticide resistance,” she said.

“Our disruptive research involves a spray of nano-sized degradable clay used to release double-stranded RNA, that protects plants from specific disease-causing pathogens.”

The research, by scientists from the Queensland Alliance for Agriculture and Food Innovation (QAAFI) and UQ’s Australian Institute for Bioengineering and Nanotechnology (AIBN) is published in Nature Plants.

A Jan. 11, 2017 University of Queensland press release, which originated the news item, provides a bit more detail,

Professor Mitter said the technology reduced the use of pesticides without altering the genome of the plants.

“Once BioClay is applied, the plant ‘thinks’ it is being attacked by a disease or pest insect and responds by protecting itself from the targeted pest or disease.

“A single spray of BioClay protects the plant and then degrades, reducing the risk to the environment or human health.”

She said BioClay met consumer demands for sustainable crop protection and residue-free produce.

“The cleaner approach will value-add to the food and agri-business industry, contributing to global food security and to a cleaner, greener image of Queensland.”

AIBN’s Professor Zhiping Xu said BioClay combined nanotechnology and biotechnology.

“It will produce huge benefits for agriculture in the next several decades, and the applications will expand into a much wider field of primary agricultural production,” Professor Xu said.

Here’s a link to and a citation for the paper,

Clay nanosheets for topical delivery of RNAi for sustained protection against plant viruses by Neena Mitter, Elizabeth A. Worrall, Karl E. Robinson, Peng Li, Ritesh G. Jain, Christelle Taochy, Stephen J. Fletcher, Bernard J. Carroll, G. Q. (Max) Lu & Zhi Ping Xu. Nature Plants 3, Article number: 16207 (2017) doi:10.1038/nplants.2016.207 Published online: 09 January 2017

This paper is behind a paywall.

I don’t usually do this but here’s the abstract for the paper,

Topical application of pathogen-specific double-stranded RNA (dsRNA) for virus resistance in plants represents an attractive alternative to transgenic RNA interference (RNAi). However, the instability of naked dsRNA sprayed on plants has been a major challenge towards its practical application. We demonstrate that dsRNA can be loaded on designer, non-toxic, degradable, layered double hydroxide (LDH) clay nanosheets. Once loaded on LDH, the dsRNA does not wash off, shows sustained release and can be detected on sprayed leaves even 30 days after application. We provide evidence for the degradation of LDH, dsRNA uptake in plant cells and silencing of homologous RNA on topical application. Significantly, a single spray of dsRNA loaded on LDH (BioClay) afforded virus protection for at least 20 days when challenged on sprayed and newly emerged unsprayed leaves. This innovation translates nanotechnology developed for delivery of RNAi for human therapeutics to use in crop protection as an environmentally sustainable and easy to adopt topical spray.

It helps a bit but I’m puzzled by the description of BioClay as an alternative to RNAi in the first sentence because the last sentence has: “This innovation translates nanotechnology developed for delivery of RNAi … .” I believe what they’re saying is that LDH clay nanosheets were developed for delivery of RNAi but have now been adapted for delivery of dsRNA. Maybe?

At any rate this paper is behind a paywall.