A single class of medications accounts for 40% of all prescription drugs in indications ranging from cancer to diabetes. Healthcare analysts Kristine Harjes and Max Macaluso discuss the importance of these drugs and some key names to know, in this clip of Industry Focus: Healthcare.

A transcript follows the video.

This podcast was recorded on March 10, 2016, and was released on May 18, 2016.

Kristine Harjes: The first class that we wanted to talk about, I don't know if we've ever actually mentioned these by name on the show, but we've talked about examples of them in abundance, and these are GPCRs. Max, can you take over from here? What exactly are these?

Max Macaluso: Sure. GPCR stands for G-Protein-Coupled Receptor. They're also called serpentine receptors, it's kind of a neat name, only because they're composed of seven helices that kind of line up and down in the cell membrane.

Harjes: So, like a snake?

Macaluso: Like a snake, exactly.

Harjes: Nice.

Macaluso: I mean, they don't really look like that, (laughs) but all of the images that are based on the crystal structures kind of look like that, hence the name.

Harjes: So, if you have your crayon box out, start drawing a snake.

Macaluso: Exactly. But, they're used for signalling. Essentially, something will bind to the outside of that receptor, outside of the cell, and that causes a reaction within the cell. So, it's kind of like a telegram. Someone knocks on the door, hands a telegram to the person, the person delivers the message. So, they're not actually entering through the door. They just relay a message. That's called the signal cascade

GPCRs are very prevalent throughout the body. They modulate a lot of different biological processes. So, Kristine, for instance, did you have a cup of coffee this morning?

Harjes: I did not, I'm trying to wean myself off of it. But I know plenty of people who did.

Macaluso: (laughs) I certainly did, and I like a little bit of sugar in my coffee, so, the sensation of both bitter and sweet tastes are modulated by GPCRs, as well as other senses like sight and smell. There are also cardiovascular functions, and even certain types of mood, like happiness, are modulated by GPCRs, like serotonin receptors. So, they're very prevalent for a variety of biological processes.

Harjes: So, how exactly are they important to the drug industry?

Macaluso: Well, it might be surprising, but around 30% of prescription drugs currently on the market target a GPCR. So they've been around for a long time, and it's still a very hot area of research. One example is Heptares. This is a GPCR specialist who was recently acquired for around $400 million. There are a number of companies working in this area. And also, just to put this in context, the first crystal structure of a human GPCR won the Nobel Prize in 2012. And that paper was published in 2007. Often, with Nobel Prizes, it could take a couple decades, three or four decades, to be recognized for work. In this case, it was only five years.

So, GPCRs are incredibly important to the drug industry. They'll continue to be. And there are a lot of prominent examples of drugs that target this class of proteins. Zyprexa from Eli Lilly, that treats schizophrenia is an example. You've probably heard of Clarinex as well, that's a popular antihistamine made by Merck, and Zantac, made by Boehringer Ingelheim. Those are three prominent examples.

Harjes: Yeah. To add to that list, because there really are a ton of them, we've got Advair Diskus from GlaxoSmithKline, Abilify, Oxycontin. There are really a ton of these.

Kristine Harjes has no position in any stocks mentioned. Max Macaluso, Ph.D. owns shares of Merck, Inc.. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.