What are tight intersections?

A tight intersection, also known as Zona occludens, is one of the group of intersections that connect to and into the tissues around them, helping to provide structural stability and strength. Tight intersections also allow efficient transmission of substances across epithelial cells to segregate transport proteins to different areas of the cell. The screams are located on the upper part or top of the cell and create a seal that prevents movement between the base and the peak in both directions. This means that the peak of each cell effectively forms a section separate from the base. Tight intersections also stop substances passing from one epithelial cell to the next. They allow some molecules to go through, but otherwise completely close the space between the cells. Proteins are prevented from moving in the membrane and help concentrate them in specific areas where the cardmes are between the cells. This provides a way of allocating different functions for separate cell parts.

For example, epithelial cell -lining cells allow nutrients from the intestinal content to pass through their apical surfaces. The nutrients then move through their basal and side surfaces to achieve extracellular fluid and cross the blood vessels. Two different sets of transport proteins are needed for this process, one on top and one on the base and on the sides of the cells and tight intersections ensure that they remain in their relevant areas. The molecules are also prevented from returning to the intestine through the premises between the cells, as the tight intersections are sealed. Sometimes epithelial cells are able to adjust tight intersections to allow additional water and substances, for example, when concentrations in the intestine increase after meals.

tight intersections consist of and the sealing springs that hold the plasma membranes together. They are mostly made up of a group of proteins called Claudins. Other types of intersections include anchoring intersections that connect cellular cytoskeletons dummyADY A are made of proteins of cadherin or integrin. Cytoskeletons are fibers that give the shape of cells. Finally, the gaps directly allow the molecules between the cells.

Zonulin is a protein that regulates the permeability of tight intestines in the intestines and is expected to play a role in autoimmune diseases such as celiac disease and diabetes. In celiac disease, gluten consumption leads to high zonulin levels to allow the intestine to release than usual. The gluten then enters the blood and induces an autoimmune response where antibodies focus on the intestine leading to symptoms such as abdominal pain and diarrhea. Treatment generally involves avoiding gluten in the diet, but drugs formed to block the action of zonulin could prove to be useful in the wg.