It turns out that `` wireworm '' that parasitizes insects and manipulates behavior has lost genes that exist in all other animals



Wireworms are thin thread-like parasites that parasitize insects such as praying mantises and grasshoppers, and are known for their ecology that manipulates the host's brain and jumps into the water. As a result of investigating two genetically distant species among such wireworms, it was found that wireworms lack the gene that expresses the `` cilia '' organelle that is present in all other animals.

Rampant loss of universal metazoan genes revealed by a chromosome-level genome assembly of the parasitic Nematomorpha: Current Biology
https://doi.org/10.1016/j.cub.2023.07.003



“Mind controlling” parasitic worms are missing genes found in every other animal - Field Museum
https://www.fieldmuseum.org/about/press/mind-controlling-parasitic-worms-are-missing-genes-found-in-every-other-animal

Mind-Controlling Worms Are Missing a Feature Common to All Other Animals : ScienceAlert
https://www.sciencealert.com/mind-controlling-worms-are-missing-a-feature-common-to-all-other-animals

Missing genes in 'mind-controlling' worms pose an evolutionary puzzle | CNN
https://edition.cnn.com/2023/07/18/world/horsehair-worms-parasites-missing-genes-scn/index.html

There are various ecological creatures in the natural world, but wire bugs are one of the most strange creatures among them. Wireworms are very long and thin, with a body length of several centimeters to one meter.

Wireworm eggs hatch in water and first parasitize aquatic insects. When the aquatic insect emerges and flies on land, it is eaten by praying mantis, etc., or for some reason it is eaten by grasshoppers etc. with larvae or dormancy, and this time it parasitizes in the body of terrestrial insects. Adult wireworms inside terrestrial insects manipulate their ability to detect 'horizontally polarized light' contained in the reflected light of water, causing them to jump into the water where they reproduce.

``One of the coolest and best-known things about wireworms is that they influence the behavior of their hosts, making them do things they wouldn't do if they weren't infested,'' said Tauana Cunha , a postdoctoral fellow at the Field Museum of Natural History and lead author of the paper.

Although the bizarre ecology of these wireworms has been well studied, genetic research on wireworms has not progressed so much. Therefore, in order to learn about the evolutionary relationship between wireworms and other animals, the research team of Cunha et al. Collected the DNA of the freshwater wireworm Acutogordius australiensis and the saltwater wireworm Nectonema munidae, and conducted research to determine the genome sequence of each.


by

Mark Yokoyama

The analysis revealed that these two far-flung species of wireworms had something in common: they lacked about 30% of the gene set thought to be present in all animals. The missing gene group in the two species was almost the same, and this missing was not something that could be cleared up by the research team's mistakes or by chance.

When we investigated the functions of the gene clusters lacking in wireworms in other animals, we found that these gene clusters are involved in the development of cilia, one of the organelles. Cilia are present in a large number of animal cells, and human sperm cells and retinal cells also have cilia. ``Ciliae are cellular-level organelles that are present in basically all animals, and are also present in protozoa, some plants, and fungi, in short, in a wide variety of life on Earth.

Researchers had previously found that wireworm sperm cells lacked the cilia found in other animals, but that wasn't considered evidence that they didn't have the gene. ``Previous observations did not appear to have cilia in wireworms, but we did not know for sure,'' Cunha said. ``When we analyzed the genome this time, we found that there were no genes that express cilia in other animals.



Because host-parasitic organisms rely on their hosts for a variety of behaviors for survival, they often lack organs that are present in other animals. However, since there are many parasites other than wireworms that have genes that express cilia, it cannot be said that the lack of genes found in wireworms is due to the ecology of parasitic insects. On the other hand, the lack of a common gene in two genetically separated wireworm species suggests that the deletion likely occurred fairly early in wireworm evolution.

in Science,   Creature, Posted by log1h_ik