AM - Cytoskeleton (1) Flashcards
1
Q
What are some functions of the Cytoskeleton?
A
- Provide stability for the cell
- Organisation and Transport of organelles
- Involved in cell division
2
Q
What 3 components are present in the cytoskeleton?
A
- Microfilaments
- Intermediate filaments
- Microtubules
3
Q
What do microfilaments consist of?
A
- Linear assemblies of actin monomers
- 2 strands of F-actin which twist around each other
4
Q
How is actin assembled?
A
- Pear-shaped and hence has polarity
- Consists of a BARBED and POINTED end
5
Q
What type of structure is the cytoskeleton?
A
Dynamic
6
Q
How are microfilament branches synthesised?
A
- ARP2/ARP3 complex acts as a primer for actin polymerisation
- Allows the binding of actin filaments and so results in the branching of the microfilament network
7
Q
How is actin polymerisation regulated?
A
Profilin and Thymosin levels
- Profilin promotes rapid plus-end growth
- Thymosin prevents plus-end growth
8
Q
How is microfilament length regulated?
A
- Gelsolin can cause cleavage of the microfilament
- The Gelsolin/microfilament complex can act as a primer for chain elongation
9
Q
How is the association of microfilaments regulated?
A
Filamin homodimers crosslink microfilaments forming a gel-like network
