Question

What do tight junctions and adherens junctions have in common?

Answer 1

Ans- Cell junctions- The cells in tissue are linked to one another and to the extracellular matrix at specialized contact sites called cell junction. There are different reason for Tight junctions and adherens junctions-

Tight junctions {zona occludens}- The tight junction are cell-cell occluding junctions mediated by two major transmembrane proteins-claudins and occluding.

Tight junctions make the closest contact between adjacent cells and prevent the free passage of molecules {including ions} across an epithelial sheet in the spaces between cells.

They also maintain the polarity of epithelial cells by preventing the diffusion of molecules between the apical and the basolateral regions of the plasma membrane.

Adherens junctions- Its junctions connect bundles of actin filament from cell to cell 'or' from cell to the extracellular matrix and belongs to the cadherin family. adhesion belts are usually located near the apical surface, just below the tight junctions