Roles Of Cytoskeleton Flashcards
Six main roles of cytoskeleton
- Establishment of cellular polarity
- Directional migration
- Formation of bipolar spindles
- Chromosomal segregation
- Cytokineis
- Intracellular transport…
What structure is in the microvilli?
Tubulin (microtubules)
What structure makes up the terminal web
Actin
What are IF’s associated motors?
None known
Is IF dynamic? If so, how controlled?
Yes, by phosphorylation
Name two examples of IF’s
Keratin, nuclear lamins
What is the basic structure of IF?
2 chained coiled coil forms tetramer
Is the overall structure of intermediate filaments polar or apolar? Parallel or aparrallel
Nonpolar (sit in middle)
Aparrallel
Actin has __ and __ ends
Plus minue
Monomer of actin filaments?
Globular protein G-actin that contains a bound nucleotide (ATP or ADP)
Polar - actin filaments?
Yes. Plue and minus
Which end is faster growing in actin?
Plue
`Dimers of tubulin - describe:
Polymers of alphabeta tubulin, alpha and beta bound to ATP. Polar
ATP-actin is preferably added to which end?
The barbed or plus end
Is ATP hydrolysis required for actin polymerization?
No; influences stabilization
In actin filaments AND microtubules, Polymerization is followed by… Keep going…
Hydrolysis, catches up to minus but not plus end.
In MICROTUBULES, the plus end transitions between ___ & ____
Growth and shrinking
Is actin highly regulated by binding proteins?
Yes
4 structures made of microtubules
Cilia, flagella, centrioles, and basal bodies
Acronym - microtubules
Many cities create fun bars
Microvilli has filaments of
Actin
Primary cilium - motile or non-motile?
Non-motile
Detection of motile cilia
9 doublets and 1 central doublet
Microtubule associated proteins are called
MAPs
For the microtubules to “reach” the cell periphery, what proteins inhibit catastrophies by binding to and tracking the + end of a growing microtubule?
+ tip proteins
What toxin stabilizes Actin filaments?
Phalloidin
What toxin depolymerizes microtubules?
Colchicine
What toxin binds and stabilizes microtubules?
Taxol
Two drivers of cellular movement That are both cytoskeleton dependent?
Motor-driven or polymerization driven
Intracellular transport can be driven in which two ways?
Motor-driven or polymerization-driven
What is the role of dynamic actin filaments in cellular function?
Actin polymerization alone can drive cell migration; certain bacteria commandeer the cell’s actin polymerization machinery during infection.
