6. Contractile Protiens Flashcards
Where do you see ATPase activity in Myosin?
In the Head region
What is a contractile ring made of?
Actin and Myosin II
What is the function of Myosin VI?
Moving vesicles towards the negative end of actin.
What actin bundling protein is present in contractile bundles?
Is this a tight or loose bundle?
Alpha-Actinin
Loose
Which end of actin does myosin move towards?
The plus end
On which end of actin do we typically see growth?
The plus end
What enzyme in smooth muscle activates myosin?
Myosin Light Chain Kinase
What actin bundling protein would you find cross linking the actin in a microvillus?
Why?
Fimbrin
Fimbrin holds actin fibers close together, which is more beneficial in a microvillus
What does the Dystrophen Gene do?
Connects Cytoskeleton to the basal lamina, stabilizes the membrane, and in so doing, helps to relieve the stress of contraction by spreading the forces out.
For Filamin:
Where are its actin binding domains located?
At the farthest ends of a dimerized structure
In a sarcomere, which side of the actin would be the plus side?
The side attached to the Z Disc
What is the function of Myosin I?
Assists with endocytosis
What causes a myosin “power stroke?”
Release of Pi
In a sarcomere which side of the actin would be the minus side?
The side farthest from the Z Disk (in the A Band)
Which myosin might you find associated with a membrane?
Myosin I