Cell-Cell Junctions

Hi in this video we're gonna be talking about cell to cell junctions. So what is the cell to cell junction? Well, it's a junction that connects cells together. Now there are many different types based on what kind of molecules are being used. So let's go through them. The first, it's called the adherents. You may say this is the anchoring junctions and these anchor cells together. So can adherents are the important protein here but they also acted is also another important. So the cat hearings and anchoring junctions are angered to act in. So here's here's like a zoomed out version of two cells with an adherent junction with acting in them. And then here's the zoom in. So you have the cat hearing and if you follow the cat here and through to the inside of the cell, it's going to be connected to acting filaments. So that's the adherence junction. Then we have the Dismas OEMs. And these asked to bind epithelial cells to each other. So cat hearings are also important here. But they instead linked to intermediate filaments instead of active filaments. Now there is a similar structure called a hemi Dismas OEM. And this links epithelial cells to the basil lamin A. Instead of epithelials to each other. So this is a little bit different interaction. So here's the Desmond's omit looks very similar. You have these cat hearings and if you follow them through they're going to be linked to different types of internal filaments, including the intermediate developments. So that says Mazzone's then we have what's known as the tight junctions or the including junctions. And these form seals between cells that prevent leakage of water ions between the cells. So the proteins that make up tight junctions are called Kloden zor ACLU Dent's and these are really important and creating polarized regions and cells. So the a pickle or the basil surface. So here we have an example. So obviously this surface here is the a pickle and this surface here is the basil surface and they look different. They have different proteins on them. And the reason is because there are tight junctions that sit here that separate the proteins found here from going to any other membrane. So if you zoom in on those tight junctions, what you see as you get proteins that all these different types of proteins are coming in and forming these really tight interactions between these two cells. And so what it prevents is from proteins from going from the local side to the basil side and also prevents water or other ions from flowing through these areas. So that's tight junctions. And then finally, we have not finally, but one of the final ones we're going to talk about is the gap junction. And these are regions of the plasma membrane that align and parallel to connect. So the proteins here are called connections. These are cylindrical proteins that adjoin the adjacent membranes. And this these types of junctions allow water and are inorganic ions to pass between the side of cells. So here we have one plasma membrane and here we have another. There's some intracellular space here. And you can see these gap junctions are forming um with connections that allow for water and organic molecules to pass super important. And then finally we have the last one which we have talked about before. This is plasma. Does model, they connect plant cells together. You can see them here, which you've seen these images before. So I'm not going to spend a ton of time but you can also see them here where you have different um plasma does model connecting the side of cell of one cell to the side of all of the other. So those are the different types of cell junctions. So let's now move on.