Researchers explain how animals sense potentially harmful acids

May 16, 2011
Proposed model for how acetic acid might activate the ion channel TRPA1. A new study in the Journal of General Physiology identifies TRPA1 as the sensor in animals responsible for identifying weak acids, an important class of potentially harmful chemicals. Credit: Wang, Y.Y., et al. 2011. J. Gen. Physiol. doi:10.1085/jgp.201110615.

All animals face the challenge of deciding which chemicals in the environment are useful and which are harmful. A new study greatly improves our understanding of how animals sense an important class of potentially harmful chemicals: weak acids. The study appears online on May 16 in the Journal of General Physiology.

Weak acids like acetic acid (vinegar) and propionic acid (present in fermented foods like Swiss cheese) are shunned by many animals, and with good reason. Many in the environment can have widespread detrimental effects. Humans ingest these substances despite the fact that they actually elicit "irritating" sensations, a that may have been vital for our ancestors' survival.

So what are the molecular sensors and mechanisms involved when animals detect these substances? Although researchers have identified sensors for many , the mechanisms involved in the detection of weak acids have been a mystery. Now, University of Southern California researcher Emily Liman and colleagues identify the sensor as none other than the ion channel TRPA1. The authors show that TRPA1 responds to weak acids when they acidify the cytoplasm within the cell. Such cytoplasmic acidification can have very —even triggering cell death—which explains why this process raises such alarm bells in animals.

Researchers have been surprised in recent years to discover how many different types of noxious stimuli can be sensed by TRPA1, explains Brandeis University's Paul Garrity in a Commentary accompanying the study. With this latest research, weak acids can be added to that growing list.

More information:
Garrity, P.A. 2011. J. Gen. Physiol. doi:10.1085/jgp.201110657
Wang, Y.Y., et al. 2011. J. Gen. Physiol. doi:10.1085/jgp.201110615

Related Stories

Recommended for you

Gut microbes signal to the brain when they are full

November 24, 2015

Don't have room for dessert? The bacteria in your gut may be telling you something. Twenty minutes after a meal, gut microbes produce proteins that can suppress food intake in animals, reports a study published November 24 ...

New findings offer hope for diabetic wound healing

November 23, 2015

University of Notre Dame researchers have discovered a compound that accelerates diabetic wound healing, which may open the door to new treatment strategies. Non-healing chronic wounds are a major complication of diabetes, ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.