Cooling Sensation: Lipid Enzyme & Temperature Regulation
- fruit flies' remarkable ability to detect minute temperature changes relies on a precisely maintained thermosensory system.
- The study, led by Takaaki Sokabe and Xiangmei Deng at the Exploratory Research Center on Life and Living Systems (ExCELLS), focused on ionotropic receptors (IRs), specifically IR25a and...
- Deng noted the revelation of bishu-1's role was unexpected.
Fruit Flies’ Acute Temperature Sensing Mechanism Unveiled
fruit flies’ remarkable ability to detect minute temperature changes relies on a precisely maintained thermosensory system. Researchers have now identified a key component in this process: a lipid enzyme called bishu-1. This enzyme regulates the expression of thermal receptors, influencing the insects’ cool temperature sensation and avoidance behaviour.
The study, led by Takaaki Sokabe and Xiangmei Deng at the Exploratory Research Center on Life and Living Systems (ExCELLS), focused on ionotropic receptors (IRs), specifically IR25a and IR21a. These receptors, found in cool temperature-sensing neurons in larval heads, mediate the flies’ avoidance of cool temperatures. The team discovered that bishu-1 maintains the transcriptional level of IR25a and IR21a,thus enabling cool temperature sensation.
Deng noted the revelation of bishu-1’s role was unexpected. Monoacylglycerol acyltransferases (MGATs) are typically associated with energy storage in the liver or intestine. the gene was named “bishu,” a Chinese term for “summering,” after researchers observed the mutant larvae avoiding warm temperatures.
Unlike other lipid enzymes that directly interact with sensory receptors, bishu-1 regulates the expression of receptor genes. It is essential for the expression of the transcription factor broad, which binds to the regulatory region of the IR25a gene. Overexpression of broad was sufficient to correct the cooling response defects seen in bishu-1 mutant larvae.
“Regulation of gene expression levels represents a novel role for lipid metabolism in the nervous system,” Sokabe said.
Sokabe added that because broad is widely expressed in neurons and IRs play a role in chemical, thermal and humidity sensation, further research into other MGAT-coding genes could reveal how lipid enzyme-mediated mechanisms effect multiple sensory processes.
What’s next
This research may pave the way for lipid-mediated treatments to maintain thermosensation and other sensory systems in humans.