Cell VI Flashcards
How to Tau tangles appear with E staining?
“Flame” inclusions
tau tangles are c/w what disease?
Alzheimers
Microtubule assembly occurs at what end? Disassembly?
Assembly at the + end
Disassembly at the - end
Where is myosin located in muscle cells?
A band
Where is actin filaments located in muscle cells?
I band
What are the molecules that stabilize microtubules?
Microtubule-associated proteins (MAPs)
What are examples of MAPs?
MAP-1-4, MAP-τ (tau), and TOGρ
What is the diameter of microfilaments?
6-8 nm
What are the subunits that comprise microfilaments?
Actin
What is the drug discussed in class that inhibits the polymerization of actin?
Cytochalasin B
What are the five functions of microfilaments?
- Structural support (cell cortical fibers)
- Form core of microvilli and stereocilia
- Movement
- Cytokinesis
- Formation fo filopodia and lamellipodia
What is the diameter of thick filaments?
12-16 nm
What is the proteins that makes up thick filaments?
myosin
mutation in the gene encoding the protein myosin causes what?
Cardiomyopathy
What is the diameter of intermediate filaments?
10 nm
What are the six types of intermediate filaments?
- Cytokeratin
- Desmin
- Vimentin
- Neurofilaments
- Glial fibrillary acidic proteins
- Nuclear lamins
What is the general function of the intermediate filaments?
Structural support
Why would you want to analyze a CA cell for the type of intermediate filaments?
To determine where the tumor came from. Changes the therapy
Where is cytokeratin found? What does it form?
Found in epithelial cells where it forms tonofilaments
What are mallory bodies found in?
Alcoholic liver disease
What is Epidermolysis bullosa simplex?
Mutations in keratin 5 or 14 gene prevent keratin from assembling into strong networks b/t dermis and epidermis.
Epidermis of skin becomes fragile, and blisters easily.
Where is the intermediate filament Desmin found?
Striated muscle and non-vascular smooth muscle
Where is the IF Vimentin found (2)?
Fibroblasts
Chondroblasts
Where are neurofilaments found? Mutations in them are associated with what?
Found in nerve cells
Mutations = neuropathies
Where are glial fibrillary acidic proteins (GFAPs) found in?
Astrocytic glial cells
Aggregates of GFAP are demonstrated in what disease?
Alexander’s disease (white matter disease)