Cytoskeleton Actin Structure

Home > Flashcards > Print Preview

The flashcards below were created by user p.reilly1227 on FreezingBlue Flashcards. What would you like to do?

  1. What is the width and subunit composition of Microfilament (2), Microtubule (3), and IF(4)?
    • Actin (/MreB): 7-9 nm
    • Alpha + Beta Tubulin dimer: 25 nm (hollow)
    • Lamins, Desmin, Keratin, Neurofilaments: 10 nm
  2. Specifications of Actin:
    • Highly conserved
    • Most abundant Eukaryotic protein
    • G-Actin + F-Actin forms
    • Complexed with ATP-Mg or ADP-Mg
  3. G and F- Actin sturcture
    • G-Actin: Monomer with 4 domains. domains II+IV= (-) end I+III=(+) end and a cleft for ATP on the (+) end
    • F-Actin: Homomer made of G-Actin monomers the form a left handed helix (pointed end = (-); Barbed end = (+))
  4. Define: Cc
    +/- side characteristics + [Cc]
    • Cc: the concentration of G-actin required for monomer assembly into filaments.
    • + side has a lower Cc which allows it to assemble in one direction
    • [+] = .12 uM [-] = .6 uM
  5. Different Cc allow for ______ which is the process by which a cell moves its membrane.
    Treadmilling: Cc of cell is inbetween + and - end which allows forward movement and is powered by ATP hydrolysis
  6. The 3 phases of Actin polymerization are:
    Nucleation - Elongation - Stablization
  7. Drugs that restrict actin assembly include:
    • Cytocholasin D: Bocks + end assembly
    • Latrunculin: Blocks G-actin addition
  8. Drugs that stabalize actin fimalaments:
    Phalloidin: Used as actin specific stain
  9. 2 proteins that regulate actin polymerization are:
    • Thymosin Beta: binds G-Actin 1:1 and prevents assembly
    • Profilin: Promotes ATP binding (+ end assembly) and binds to PIP2 at membrane

Card Set Information

Cytoskeleton Actin Structure
2011-10-05 20:27:38
Actin Cytoskeleton two

Cytoskeleton Actin Structure
Show Answers:

What would you like to do?

Home > Flashcards > Print Preview