 I think by far the easiest way to make sense of that pattern is to draw it. So we have something that looks almost like a beat-a-meander but not quite. Let me start by drawing a bunch of isolated beta strands, a total of eight of them. One, two, three, four, five, six, seven, and eight. One, two, three, four, five, six, seven, eight. Yes. If you're ever going to draw this, there are three tricks because this looks easy when I draw it for you, but if I ask you to draw it, you're going to make mistakes. First trick, always start at number three. That will help you. Second is two short plus two long loops. And third, they go in opposite direction. For instance, the short go back and the long go forward. Let's see how far that takes us. I'm going to start at the third. So I'll put my N-terminus there. And then I do one loop back, two loops back, both of them are short. Long loop forward, long loop forward. Short loop back, short loop back. Long loop forward. Yes, and then I would continue with that with the C-terminus. We can draw this schematically too with the type of cartoons I've showed you. The Helix series and extra item, but this is a typical small protein that has a key of this part. Regular patterns like this, you've occasionally heard me use the word motif perhaps, and that's typical to recall them. Motifs for pattern or perhaps super secondary structure motif in this case. This, if you have a best of fun artistic gene here, you might see that this is a two-dimensional pattern that you can draw without lifting the key. And this type of pattern actually occurs in art everywhere and it's done so for millennia, in particular on Greek urns. The pattern that this one is called is Greek key. There are slightly different variants of it than it's primarily, what I've done is primarily similar to the lower one here. This parallel was noted by Jane Richardson who published the Greek key motif in Nature in 1977. And again, you can draw a seat on a Greek urn like this. Jane has been awarded numerous prizes for this, not the Nobel Prize. She would like to have been worth one and she probably was nominated, I have no idea. But in particular by the National Academy of Sciences a few years ago. So how do you use this for something like the gamma crystalline? Well, first it's just a way to organize loops, right? But in many cases we might need slightly longer loops. There is nothing wrong with those short loops of the fatty acid binding protein, but the short loops of the fatty acid binding protein also means that the interior is somewhat exposed. Now that's fine in many cases. In the fatty acid binding protein case, you likely want to expose the interior so that a fatty acid can diffuse in, bind there and then diffuse out again. But in other cases, such as the gamma crystalline, we probably rather want the compact structure that is locked up from the left and locked up from the right, top, bottom and forward, back. So you create a proper interior. And these loops help you have some building material on the bottom and top of the beta sheets to create that locked up interior. In other cases, there could be binding side reasons why you just need these long loops. And second, when it comes to building structure, we will of course have more diversity, more possibilities for entropy, if we can use longer loops too, not just the very short ones. So again, this is the Greek key motifs, and it's something you should remember. It's possibly the most common and well-known super secondary structure motif in amino acids. Bye, Jane Richardson.