Lecture 9 - Structure of Epithelia Flashcards
What determines transport properties of tight junctions/paracellular pathways?
Claudins
What does claudin 1 do?
The presence of claudin 1 means that the TJ will be impermeable to ions (such as NA+) and water. This
Where might we find tight junctions with claudin 1?
Skin and glomerulus
What does claudin 2 do?
Claudin 2 allows for the transport of many ions and water through the TJ. It is found in areas that do not need as much control over where Na+ and water absorption is required
Where might we find tight junctions with claudin 2?
intestinal crypts and the proximal renal tubule
What transmembrane proteins are found in tight junctions?
Claudin
Occuldens
JAM
What transmembrane protein is found in adherens?
E-Cadherins
What transmembrane protein is found in desmosomes?
Desmosomal cadherins
What transmembrane protein is found in gap junctions?
Connexins
What are the cytoskeletal attachments of adherens?
Actin filaments
What are the cytoskeletal attachments of desmosomes?
Keratin filaments
What are the cytoskeletal attachments of hemidesmosomes?
Keratin filaments
What ZO proteins connect to cytoskeleton?
ZO1-3
Patients presenting with epidermolysis bullosa present with severe blistering BECAUSE collagen dysfunction prevents proper anchoring of basement membrane to the epithelial cell
A- Both true and related
B- Both true and not related
C – First statement true, second false
D – First statement false, second true
E- Both false
A- Both true and related
Desmosomes connect epithelial cells to the basement membrane BECAUSE the basement membrane consists of extracellular matrix proteins
D - First false, second true
