CAMs Flashcards
What are the two calcium independent CAMs?
integrins and immunoglobulin superfamily
intermediate protein that links cadherins to actin of the cytoskeleton
catenin
CAM that binds neighboring cells together, calcium dependent
cadherin
three classical kinds of cadherins
E cadherins (epithelial) N cadherins (neural) P cadherins (placenta)
these CAM bind to carbohydrates at CRD extracellularly with the help of calcium and help leukocytes get from the blood to tissues
selectins
three classes of selectins
P (platelets)
E (endothelial)
L (leukocytes)
this CAM binds extracellularly to fibronectin and laminin (basement membrane or extracellular membrane) at the RGD sequence
integrin
these CAMs have an extracellular component. the two classees are N CAM and I CAM
n cam- neural adhesion
i cam- mediate leukocyte migration
IMMUNOGLOBULIN SUPERFAMILY
characteristics of epithelium (9)
- it is composed majorly of cells (very little matrix)
- arranged in sheets
- covers/lines/protects/secretes
- has a free surface (apical) and bound sides (basolateral)
- is polar
- receives blood by diffusion (not vascularized)
- innervated
- tightly bound by junctions
- regenerative (mitotically active)
2 components of basement membranes
basal lamina and reticular lamina
basal lamina is composed of what
laminin, fibronectin, type IV collagen, entactin, proteoglycans
this layer of the basement membrane is in contact with underlying connective tissue, it’s made of reticular fiber and glycoproteins
reticular lamina
what are the 3 categories of junctional complexes in epithelial cells
adherins, occludens, gap junctions
this junctional complex anchors cells together to reinforce the tissue integrity (and is associated with cadherin filled junctions)
adherin
this type of junctional complex is also known as a tight junction because it creates an impermeable barrier between cells that prevents transport to maintain concentration gradients
occludens
gap junctions
composed of pores called CONNEXONS (made of 6 connexins) to allow ion/ small molecule exchange between cells
this junctional complex can be of adherin or occluden variety
zonula
this junctional complex is a belt like junction (wraps all the way around cell) that associates with intracellular actin
zonula
this junctional complex is of the adherins family and is a “snap like junction” that associates with intracellular intermediate filaments
macula (aka desmosome on lateral surface or hemidesmosome on basal surface)
This junctional complex mediates adherin junctional complexes.
cadherins (desmoglein in the epidermis or desmocollins)
disease attacking desmoglein of epidermis causing dissociation of layers and blistering
pemphigus foliaceus
What are the 2 classes of calcium dependent CAM’s?
Cadherins and selectins
