In: Biology
What type of cellular junction connects cells in your small intestine?
Intestinal epithelial cells barrier functions are mainly performed by cellular junctions such as gap junctions, desmosomes, adherence junction and tight junction.
Gap Junction
Bring adjacent cells within 2nm.It consists of protien encoded by annexin and form multiprotien hexamer protien. Seen in cellwalls of two adjacent cells and allow molecules, ions and electric impulse to pass between cells.
Adherence junction
Catenin and cadherin multiprotien complexes are present which are seen in the contact points between intestinal cells.It helps to regulate epithelial migration, cell polarity and formation of other cell junction.Its main function is the interaction between transmembrane protiens and actin cytoskeleton.
Tight junction
It is also called zonula occludens has an important function in barrier mechnism of epithelium. Made up of claudin and occludin family seen in borders of lateral and apical membranes.They are ribbon like and connect the adjacent cells and form tight seal.Its function involves interaction betweencis and trans protiens and with homophilic and heterophilic protiens.Tight junction interacts with scaffold, adapter and signalling complexes and acts as selective semipermeable paracellular barrier and prevent the entry of foriegn particles.
Desmosomes
Cadherin adhesion transmembrane protiens connect between 30nm between cells and link adjacent cells through their cytoskeleton.