Mice have a way of detecting carbon dioxide, and new research from Rockefeller University shows that a special set of olfactory neurons is involved, a finding that may have implications for how predicted increases in atmospheric carbon dioxide may affect animal behavior. The finding is reported in the August 17 issue of the journal Science.
Most olfactory sensory neurons express odorant receptor molecules and reside within the lining of the nasal cavity that detect odors. But a small subset express an enzyme called guanylyl cyclase-D (GC-D). Peter Mombaerts, professor and head of the Laboratory of Developmental Biology and Neurogenetics at Rockefeller, and Andreas Walz, a research associate in Mombaerts' lab, created a strain of mice in which GC-D expressing neurons glow with a green fluorescent protein. These GC-D expressing neurons also project their nerve endings to an unusual structure in the back of the olfactory bulb called necklace glomeruli, which resemble a string of beads.
The Rockefeller team's collaborators in China, led by Minmin Luo at the National Institute of Biological Sciences in Beijing, found that all the GC-D expressing neurons in the olfactory epithelium were activated by exposure to carbon dioxide. Conversely, all the cells in the lining of the nasal cavity that were activated by carbon dioxide are the GC-expressing neurons.
"These findings show that a specialized subsystem has evolved in the mouse to detect carbon dioxide," says Mombaerts.
Carbon dioxide makes up about four-hundredths of one percent of the atmosphere. To determine the threshold for carbon dioxide detection in the mouse, the Beijing team trained mice to lick water when they received a whiff of air with higher levels of carbon dioxide. As the amount of carbon dioxide in the whiffs of air was decreased, the accuracy of the animals' response became random. Statistical analysis fixed the threshold for detection at about six-hundredths of a percent, just above the average atmospheric level.
Mombaerts cautions that scientists still do not know if the GC-D enzyme is responsible for detecting carbon dioxide. "GC-D is a marker for the neurons that have specific carbon dioxide sensitivity," Mombaerts says. "At this time, we have not shown that the marker is mechanistically involved in sensory perception of carbon dioxide." The research does, however, suggest that scientists need to be on the lookout for behavioral changes in animals as carbon dioxide levels increase in the atmosphere, since, at some point increased levels may be detectable by animals, Mombaerts says.
"Animals may adapt to this gradual and persistent increase. Alternatively, the change may induce behavioral changes, such as an increase in irritability and aggression or a decrease in fertility," he says.
Zach Veilleux | EurekAlert!
Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover
First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
17.08.2018 | Physics and Astronomy
17.08.2018 | Information Technology
17.08.2018 | Life Sciences