FOM 3.4.1 Flashcards
What are the five type of cellular motility?
Scaffolds, Motors, and Traction Cell Division Transport Ameboid Movement Cilia/flagella
What are the four motors?
Mysoin I & II, Kinesin, & Cytoplasmic dynein
Which motor of the four only has one head?
Myosin I
What type of filament does each of the motors bind?
Mysoin I & II: Actin Kinesin & Cytoplasmic Dynein: Microtubule
What is the direction of movement of the motors?
Mysoin I & II, Kinesin : Plus Cytoplasmic Dynein: Minus
What are the components of the dynein complex? And what is each pointing to?
(5)Dynein, (4)Arp1 filament, (3)spectrin, (2) ankyrin, (1) membrane glycoprotein and vesicle
What must kinesin do while walking towards the plus end of a MT?
It must keep one leg bound at all times. ATP is used to walk along.
In axonal transport, which motor carries signals down the axon while another motor carries the recycled synaptic vesicle back?
Kinesin, Cytoplasmic dynein
Crowd surfing is analogous to what?
Microtubules or Actin gliding over motors
What are the three mechanisms for ameboid movement?
Actin based (majority) MT based Focal Adhesions (FA)
What is the name for the projection that extends away from the nucleus?
Lamellipodium
When a cell forms a lamellipodium, does unpolymerized actin move towards or away from it?
Towards
Actin is concentrated at the edge of newly forming projections. What is actin mixed with right behind that edge?
Cofilin
What site does integrin bind on fibronectin and laminin?
RGD (arginine-glycine-aspartic acid)
When a microtubule comes in contact with a focal adhesion, what are the two things that can happen?
1) MT can lose its GTP cap and rapidly breakdown 2) The FA can be signal to disrupt or break apart
Do MT’s grow towards the leading edge where FA’s are being formed?
Yes, the MT can travel over the top
What type of attraction exists b/t MT & FA?
Fatal attraction
For a an in situ cancer to become invasive, what must it do? What molecules does it use to perform this action?
It must dissolve the basement membrane. To do so, cells produce MMPs (Matrix MetalloProteinases)
What are MMPs involved in?
Embryonic development, tissue morphogenesis, wound repair, inflammatory dz, cancer
MMP-2 degrades what type of collagen?
Type IV
What cleaves Pro-MMP-2?
MT-MMP-1
Active MMP-2 is completely inhibited by the binding of what?
TIMP-2 (Tissue Inhibitors of Matrix MetalloProteinases)
What is the complex that can activate Pro-MMP-2?
Dimerized MT1-MMP docked on CD44H in association with TIMP-2. (All 4 parts must be present)
What is the motor of cilia and flagella (made of MT)?
Dynein
With an anchor, dynein would produce MT sliding. Because the MT’s are anchored in cilia/flagella what is the result of dynein’s action?
Bending
Do cilia have mechanical stimulation? What molecule is released and spread to surrounding cells via gap junctions?
Yes; Ca (Calcium wave)
