Creation of virus-resistant plants with artificial DNA-binding proteins

February 24, 2016, Okayama University
Figure 1: Creation of virus-resistant plants with AZP. Give virus resistance to a plant with an artificial DNA-binding protein (AZP) that binds 1,000 times more strongly than the viral replication protein (Rep) and effectively inhibits binding of Rep to the replication origin of viral genome.

In order to resolve global food crisis, it is important to prevent plant viruses from spreading infections as they infect a wide variety of agricultural crops and significantly reduce yields. For example, gemini-virus, which forms a large family in a DNA virus, has caused over 200 billion yen worth of damage to cassava, which is a major staple food in Africa. So there is demand for effective methods to prevent such damage. A possible solution to this problem is the use of commercially available virus-resistant agricultural crops created by breeding that have some degree of resistance to viral infections. However, such crops become a new source of infection, as it is not possible to eliminate the infected virus from them. Therefore, scientists are still searching for long term solutions.

Takashi Sera and colleagues at Okayama University have developed a new for preventing DNA virus infection that is based on the idea that it is possible to prevent the development of viral infection symptoms if the virus can be prevented from growing even though it enters into a host plant.

This approach prevents viral infection by inhibiting replication protein (Rep) from binding to its replication origin by using an artificial DNA-binding protein capable of binding strongly to a target DNA sequence. To demonstrate the effectiveness of this method, the researchers used Arabidopsis, an experimental plant, and beet severe curly top virus (BSCTV), a DNA virus. BSCTV was chosen because it is known to strongly infect and kill many plants including Arabidopsis.

Creation of virus-resistant plants with artificial DNA-binding proteins
Figure 2: Creation of virus-resistant plants with AZP. Plant A is a healthy wild plant without virus infection. Inoculated BSCTV to plants B, C and D. Stem of the wild plant (Plant B) stopped growing and died 4 weeks after BSCTV inoculation. In contrast, AZP-transgenic plants (Plants C and D) showed complete virus resistance. In our AZP-transgenic plants with no symptoms, viral DNA was not detected at all by Southern blot analysis.

Based on this method, the researchers developed an artificial DNA-binding protein that binds 1,000 times more strongly than the Rep of BSCTV and effectively inhibits binding of Rep. Transgenic plants, Arabidopsis thaliana transformed with the artificial DNA-binding protein, showed no infection symptoms at all even if it was inoculated with BSCTV. Moreover, it should be noted that viral DNA was not detected in the transgenic plants. Namely, this method not only prevents targeted plants from developing viral infection, but also gives immunity (not resistance) to them.

Since the early experiments, the Okayama group have successfully demonstrated the effectiveness of this method for vegetables. "Our latest challenge is to apply this method to cereals," says Sera. "With the aim of developing a -resistant wheat, we created an artificial DNA-binding protein for wheat (designated "Wheat_AZP"). We are currently performing gene transfer into wheat to demonstrate the effectiveness of this method for cereals in the near future."

Explore further: Designer DNA-binding proteins to combat viral infections in agriculture and medicine

More information: Takashi Sera et al. Rational Design of Artificial Zinc-Finger Proteins Using a Nondegenerate Recognition Code Table, Biochemistry (2002). DOI: 10.1021/bi020095c

T. Sera. Inhibition of Virus DNA Replication by Artificial Zinc Finger Proteins, Journal of Virology (2005). DOI: 10.1128/JVI.79.4.2614-2619.2005

Related Stories

Molecular immunity from microbes

November 12, 2015

A new molecular biology tool derived from a bacterial defense system has been used for the first time by KAUST researchers to demonstrate a novel way to protect plants against viral pathogens.

Smallpox vaccine virus helps scientist understand immunity

April 15, 2015

A virus that helped wipe out smallpox in the last century is now helping a University of Nebraska-Lincoln virologist better understand human immunity. This research may lead to better treatment of some viral diseases, including ...

Recommended for you

Nanoscale Lamb wave-driven motors in nonliquid environments

March 19, 2019

Light driven movement is challenging in nonliquid environments as micro-sized objects can experience strong dry adhesion to contact surfaces and resist movement. In a recent study, Jinsheng Lu and co-workers at the College ...

OSIRIS-REx reveals asteroid Bennu has big surprises

March 19, 2019

A NASA spacecraft that will return a sample of a near-Earth asteroid named Bennu to Earth in 2023 made the first-ever close-up observations of particle plumes erupting from an asteroid's surface. Bennu also revealed itself ...

The powerful meteor that no one saw (except satellites)

March 19, 2019

At precisely 11:48 am on December 18, 2018, a large space rock heading straight for Earth at a speed of 19 miles per second exploded into a vast ball of fire as it entered the atmosphere, 15.9 miles above the Bering Sea.

Revealing the rules behind virus scaffold construction

March 19, 2019

A team of researchers including Northwestern Engineering faculty has expanded the understanding of how virus shells self-assemble, an important step toward developing techniques that use viruses as vehicles to deliver targeted ...

Levitating objects with light

March 19, 2019

Researchers at Caltech have designed a way to levitate and propel objects using only light, by creating specific nanoscale patterning on the objects' surfaces.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.