Mind-controlling worms are missing a feature common to all other animals: ScienceAlert

Some parasites have taken simple life to a whole new frontier.

Scientists recently discovered a fearsome mind-controlling worm that’s missing some essential genes in the animal kingdom.

Ironically, the super-long and thin “hairworm” (also known as the “horsehair worm”) completely lacks the “hair” at the cellular level that allows most animal cells to move, feel, or filter in fluids.

These microscopic filaments are known as cilia and protrude from the surface from nearly every cell in the human body.

Yet somehow, two hairworm species are far apart – one is freshwater based (Acutogordius australiansis) and one saltwater-based (Nectonema monidae) – I learned to live without these crucial supplements.

According to a team of researchers from Harvard University, the University of Copenhagen, and the Chicago Field Museum, both species are missing about 30 percent of genes thought to be responsible for the development of cilia across nearly all animal groups.

The authors conclude that a distant common ancestor of hairworms must have discarded these genes long ago. But why they did this remains a mystery.

Cilia are organelles, small structures at the cellular level, found mainly in all animals and even, on a larger scale, in protists, some plants and fungi. Explain Field Museum evolutionary biologist Tawana Cunha.

“So they are present across a great variety of life on Earth.”

But the hairworm is special.

In the animal kingdom, it is It is not uncommon for parasites You miss a lot of genes. Similar to hairworms, many of these creatures do not have excretory, respiratory, or circulatory systems. Instead, they rely on the bodies of other animals to do most of the hard work.

In evolutionary biology, if an animal is not “using” a structure or function, it tends to lose it gradually when it regains the cost it takes to do so.

However, the lack of genes for cilia is striking. Even hairworm sperm lack a filamentous, tail-like protrusion.

“There are plenty of other parasitic organisms that aren’t missing these specific genes, so we can’t say that genes are missing because of their parasitic lifestyle,” she says. He says Being.

Researchers have previously noted that hairworms do not have cilia in some cells. But until now, it was not clear whether this pattern was present in all cells of the parasite in all its different stages of life.

“Now with the genomes, we’ve seen that they actually lack the genes that produce cilia in other animals — they don’t have a mechanism for making cilia in the first place.” Explain Being.

“It is likely that the loss occurred early in the group’s development, and they have continued in this manner.”

The authors hope their study will help scientists investigate “the genetic mechanisms underlying parasitism” further to uncover how these strange creatures steal their entire bodies.

After infesting a cricket’s brain, the mature hairworms eat the insect from the inside out, reserving just enough of its flesh to keep it alive.

Once full, the hairworm wires up the cricket’s nervous system, moving the host’s body in spasms toward a body of water.

Once the gloomy doll is submerged in the water, the worm jumps off the ship, crawling out of the cockroach’s body in long, winding tendrils so it can reproduce.

It is possible that something in this horrific reproductive process requires specialized sensory organs that are useless to cilia. No doubt future investigations into this strange puppet master will continue to show why he is so unique.

The study has been published in Current Biology.