Evolutionary history reveals the action of fish and human acid receptors

To assess the chemical composition of food from a psychological point of view, it is important to know the actions of the receptors that interact with food ingredients. These include receptors for acidic fertilizers, which first developed during evolution in deficient fish such as coelacanth.

The 400 million years of evolutionary history of the role of both fish and human acid receptors have recently been published in the journal Genome biology and evolution by a team of researchers led by the Leibniz Institute for Food Systems Biology at the Technical University of Munich and the University of Cologne.

Fortunately, acid receptors are a relatively recent mechanism compared to other chemoreceptors, such as olfactory receptors. Protecting the spine from the consumption of potentially toxic substances has long been known.

More recent are theories that bitter receptors have other functions in addition to taste perception. These include roles in protection against pathogenic bacteria, in metabolic regulation, and possibly also act as sensitizers for endogenous metabolites and hormones.

Coelacanth and zebrafish the comparison

The team of scientists led by biologists Sigrun Korsching of the University of Cologne and Maik Behrens of the Leibniz Institute for Biology of Food Systems is now providing further evidence to support this hypothesis.

In their current study, the team compared two types of original acid receptors from coelacanth (Latimeria chalumnae) with four others from zebrafish (Danio rerio) phylogenetically, functionally and structurally. To this end, the research team, among other experiments, performed extensive functional studies using a cell-based test system as well as a computer-based modeling method. The aim was to gain an in-depth look at the evolutionary history of acid receptors to learn more about their functions.

As the results of the study show, each fish species has a pair of homologous acid receptor genes that can be derived from a primordial gene. In this regard, the spectroscopy of acid identification of these fish receptors was virtually identical despite 400 million years of unique evolution, according to the results of the action studies. “What is particularly encouraging about our results is that the original fish receptors identified substances in the cell test system that have yet to be detected by human acid receptors to date. These are into bile acid, ”says co – author Antonella Di Pizio of the Leibniz Institute.

More than 400 million years of electoral pressure

“So there has to be selective pressure at least until humans have evolved, which means that human acid receptors can still find the same acidic substances as bony fish did 400 million years ago,” taste researcher Maik Behrens concludes.

This speaks for one or more actions of acid receptors, even during human evolution. “

Sigrun Korsching, University of Cologne

“Coelacanths are carnivores. Thus, one could conclude that there is a difference in acid receptors that largely recognize steroid hormones and bile acids. protection against consumption of poisonous fish, which may contain not only bile acid but also very strong neurotoxins in their liver and gallbladder, for example, the puffer fish poisonous Arothron hispidus lives in the same waters as the coelacanth, “says Maik Behrens.

“In humans and also in zebrafish, however, it is doubtful whether such a receptor variant would be preserved from an evolutionary perspective if it did not have other functions within the body. Another argument is that for additional functions to be bitter receptors are also found on human organs such as the heart, brain or thyroid gland, “Behrens added.

One aim of his research is to help understand the effects of acidic substances on the biological level of systems, whether they have entered the body through food or whether they belong to the body ‘s own substances.