Scientists discover virus that carries DNA of black widow spider toxin

black widow spider toxin
Models of lateral DNA transfer between eukaryotes and bacteriophages.

Black widow spiders are notorious because its toxin is 15 times stronger than a rattlesnake’s. These spiders are identified by the colored, hourglass-shaped mark on their abdomens.

Now researchers from Vanderbilt University find that a tiny virus that attacks bacteria may sting like a block widow spider. The finding is published in Nature Communications.

In their study, researchers focused on a virus that could attack Wolbachia, a bacteria infecting a high proportion of insects as well as spiders, including black widow spiders.

They sequenced the genome of the virus, and found that its DNA was related to black spider toxin. They estimated that the virus, named WO, might use the gene to help attack its targets.

Researchers suggest that usually viruses steal genes from their hosts. But because bacterial viruses only attack bacteria, genes from other domains of life are often beyond their reach.

The WO virus, however, can attack Wolbachia bacteria living within the cells of insects, spiders, and other animals. This means WO escapes not only from its existing Wolbachia host, but also from the eukaryotic cells. After that, the virus particles evade the eukaryote’s immune system.

Researchers also found that WO shares a number of other segments of DNA with animal genomes. For example, it has a sequence that the eukaryotic cells found in animals use to sense pathogens.

The finding is useful to improve the current efforts that using Wolbachia to fight Zika virus. Previous research has shown that Wolbachia prevents Zika viruses from reproducing in Aedes aegypti mosquitoes that spread them.

Infecting and spreading mosquitoes with Wolbachia has been successfully field tested in countries like Australia, Brazil, Columbia, Indonesia and Vietnam.

If scientists can genetically engineer Wolbachia bacteria, it might make the bacteria produce traits that help fight against Zika virus and other agricultural viruses more effectively.

Follow Knowridge Science Report on Facebook, Twitter, and LinkedIn.

Citation: Bordenstein SR, Bordenstein SR. Eukaryotic association module in phage WO genomes from Wolbachia. Nature Communications, 7: 13155. DOI: 10.1038/ncomms13155.
Figure legend: This image credited to Bordenstein SR.