New research has discovered that a specific type of worm, a nematode worm with the title of Caenorhabditis elegans, may have similar sleeping patterns to humans and other mammals. Like humans, researchers state the nematode worm has a sleep regimen that is vital to their existence. The physical correlation between C. elegans and humans and other mammals is more obvious, but what happens in the deepness of sleep is still somewhat a mystery.
In this new research published in the journal, Genetics, researchers report that without the molecule that induces sleep, the worms are highly likely to die when exposed to noxious stimuli or a stressful environment. In their sleep state, worms are physically similar to humans and other mammals. They stop moving, uncurl their body, and relax. On scans, they are also found to have reduced neuronal activity and response to stimuli. However, if the researcher poked the worm often enough, it would wake from its slumber. Similar to humans, a worm that has been woken up repeatedly will fall back to sleep a lot faster and sleep a lot heavier than a well-rested worm.
It does not stop with the physical likeness, however. This research showed that mammals and C. elegans have similar molecules that helps regulate their sleeping patterns, including the epidermal growth factor receptor (EGFR). This finding means that, like humans, nematode worms such as C. elegans have evolutionary processes similar to our own sleep-wake cycles. Researchers hope they can learn a great deal about how our sleep-wake cycles are regulated by studying this molecule in C. elegans more closely.
Unlike mammals, the C. elegans do not have a typical day/night sleep-wake cycle. Instead, they sleep during stages of their development. Each time they enter a larval stage of development, they go to sleep. In addition to that, they will sleep for several hours after any kind of stress, including extreme temperature fluctuations or exposure to environmental toxins. The worm is much less likely to survive the ordeal if they do not get their post-stress nap.
This new research mentioned that the protein, VAV-1, – which regulates the body’s activities like reproduction, defecation, and eating – may also play a role in regulating sleep. VAV-1 helps to regulate EGFR in the neurons; therefore, it stands to reason that by genetically modifying VAV-1 to overproduce, it would affect the sleep-wake cycle in the nematode. Additionally, VAV-1 is needed for the post-stress naptime in the worm. In an extreme temperature experiment, worms that were exposed to sweltering heat were less likely to survive if they did not have adequate VAV-1 function.
It is still uncertain if the human equivalents of VAV-1 play any part in our sleeping patterns; however, the researchers are convinced that it would be worth the additional research on C. elegans, whose pattern and chemical make-up are similar to our own with respect to the sleep-wake cycle. Since the proteins, VAV-2 and VAV-3, are produced in our hypothalamus, a gland that helps regulate our sleeping patterns, it is believed they behave similarly to the VAV-1 in the worm, which will help the researchers broaden their study and results as it relates to humans.
Reference: A Conserved GEF for Rho-Family GTPases Acts in an EGF Signaling Pathway to Promote Sleep-like Quiescence in Caenorhabditis elegans Amanda L. Fry, Jocelyn T. Laboy, Huiyan Huang, Anne C. Hart, and Kenneth R. Norman GENETICS March 2016 202: 1153-1166
Author: Rachael Herman is a professional writer with an extensive background in medical writing, research, and language development. Her hobbies include hiking in the Rockies, fishing, and reading.