Cell Junctions

Zonula adherens - These are anchoring junctions that hold epithelial cells together and provide mechanical resistance. They lie right below tight junctions. They involve the use of cadherins

Zonula occludens - These are tight junctions. It seals the borders of two adjacent cells to create an impermeable membrane. It can be selectively permeable.

Desmosomes - Also known as macula adherens. This is another anchoring junction. It forms a sort of zipper through the use of desmogleins on the outside and intermediate filaments in the cytoskeleton. They form spot welds.

Hemidesmosomes - These look like desmosomes, but are different. Through the use of integrins, they connect the epithelial cells to the basement membrane.

Fascia adherens - Is found in cardiac tissue, particularly intercalated discs. It is a site that anchors actin filaments.








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References:

• http://www.ulysse.u-bordeaux.fr/atelier/ikramer/biocell_diffusion/gbb.cel.fa.106.b3/content/images/fig12.jpg
• http://www.histology.leeds.ac.uk/tissue_types/epithelia/epi_cell_junctions.php
• http://upload.wikimedia.org/wikipedia/commons/thumb/7/78/Cellular_tight_junction-en.svg/2000px-Cellular_tight_junction-en.svg.png
• http://upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Desmosome_cell_junction_en.svg/1000px-Desmosome_cell_junction_en.svg.png
• https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhrVtNDefvxm585y-STKvVPqL4KedhBezmqKGTzXv1A0-wtiqVsxBJkw__oQRu_rttG5Y6LOJlpOrD4owniRGqZL2XFdnbKHM6KtNhMkR84vXZQo8JM8kwkz4At89lwjUROBsUQFtqAJsE/?imgmax=800
• http://cardiovascres.oxfordjournals.org/content/cardiovascres/80/1/9/F3.large.jpg