When humans experience stress, their inner turmoil may not be apparent to an outside observer. But many animals deal with stressful circumstances - overcrowded conditions, not enough food - by completely remodeling their bodies. These stress-induced forms, whether they offer a protective covering or more camouflaged coloration, can better withstand the challenge and help the animal survive until conditions improve.
Until now, it wasn't clear what molecular trigger was pulled to allow this structural remodeling in times of stress. But researchers at the University of Illinois and the University of Pennsylvania have discovered the protein responsible in the roundworm C. elegans.
The free-living nematode, C. elegans, exists in a stress-resistant form called dauer in low-resource or overcrowded conditions. University of Illinois and University of Pennsylvania researchers found the protein responsible for this structural remodeling, DEX-1. The extracellular matrix protein may shed light on metastasis in human cancers and other processes involving stem cells.
Credit: Nathan Schroeder, University of Illinois
"We're using a really simple animal system to understand basic biological questions that have implications not only for nematodes, including important crop parasites, but also for higher animals, including humans," says Nathan Schroeder, assistant professor in the Department of Crop Sciences at U of I, and author of the new study published in Genetics.
When C. elegans larvae are stressed, they stop eating, their development halts, and they enter a stress-resistant stage known as dauer. In this form, their bodies become distinctly thinner and longer and develop an outer cuticle with ridges from tip to tail.
Schroeder and his team were investigating a protein called DEX-1 for an unrelated project when they noticed worms without the protein were "dumpy" in the dauer phase: they remained relatively short and round. Intrigued, the researchers decided to characterize the protein and its function in seam cells, the cells responsible for dauer remodeling.
"When we disrupted the DEX-1 protein, the seam cells did not remodel during dauer," Schroeder says. "Seam cells have stem cell-like properties. We usually think about stem cells as controlling cell division, but we found that these cells are actually regulating their own shape through this protein, and that has an impact on overall body shape in response to stress."
DEX-1 is an example of an extracellular matrix protein, a type that is extruded to form the mortar between cells. These proteins exist in every multicellular organism, not only keeping cells together but also facilitating interaction between cells. Not always in a good way; it turns out many extracellular matrix proteins, including a DEX-1 analogue, are associated with human diseases, such as metastatic breast cancer.
Schroeder says his group is interested in looking more closely at metastasis in cancers due to these proteins, but as a nematologist, he gets more excited about the prospect of understanding the basic biology and genetics of nematodes themselves, particularly parasitic species that affect crops.
"For many parasitic nematodes, when they're ready to enter the infective stage, they have a similar process. Many of the genes regulating the decision to go into or come out of that infective stage also regulate the decision to enter dauer," he says. "This research gives us insight into their biology and how they make these developmental decisions."
The article, "Epidermal remodeling in Caenorhabditis elegans dauers requires the nidogen domain protein DEX-1," is published in Genetics [DOI: 10.1534/genetics.118.301557]. Authors include Kristen Flatt, Caroline Beshers, Cagla Unal, Jennifer Cohen, Meera Sundaram, and Nathan Schroeder. The research was supported by the National Institutes of Health.
Lauren Quinn | EurekAlert!
The hidden structure of the periodic system
17.06.2019 | Max-Planck-Institut für Mathematik in den Naturwissenschaften (MPIMIS)
Tiny probe that senses deep in the lung set to shed light on disease
17.06.2019 | University of Edinburgh
The well-known representation of chemical elements is just one example of how objects can be arranged and classified
The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...
Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.
Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...
Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.
The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...
Discovery by Brazilian and US researchers could change the classification of two species, which appear more akin to jellyfish than was thought.
The tube anemone Isarachnanthus nocturnus is only 15 cm long but has the largest mitochondrial genome of any animal sequenced to date, with 80,923 base pairs....
Researchers at Chalmers University of Technology, Sweden, have discovered a completely new way of capturing, amplifying and linking light to matter at the nanolevel. Using a tiny box, built from stacked atomically thin material, they have succeeded in creating a type of feedback loop in which light and matter become one. The discovery, which was recently published in Nature Nanotechnology, opens up new possibilities in the world of nanophotonics.
Photonics is concerned with various means of using light. Fibre-optic communication is an example of photonics, as is the technology behind photodetectors and...
29.04.2019 | Event News
17.04.2019 | Event News
15.04.2019 | Event News
17.06.2019 | Information Technology
17.06.2019 | Earth Sciences
17.06.2019 | Ecology, The Environment and Conservation