5. Myosin motors Flashcards
1
Q
Diameter of class I myosin
A
10-14 nm
2
Q
Diameter of class 2 myosin
A
5-10 nm
3
Q
Diameter of class V myosin
A
36 nm
4
Q
What are class I myosins involved in?
A
endocytosis
5
Q
What are class II myosins involved in?
A
contraction
6
Q
What are class III myosins involved in?
A
Binds via adapter molecules to vesicles, microtubules, and RNA
7
Q
Mechanism of myosin movement:
A
Binds ATP, head is released from actin
Hydrolysis of ATP, myosin head rotates into cocked state
Myosin head binds the actin filament
Power stroke - release of Pi and elastic energy straightens the myosin, moves actin filament left
8
Q
Differences between myosin and kinesin mechanism?
A
Kinesin bound to MT WITH ATP and is released when ATP is hydrolysed to ADP and Pi
Myosin bound to actin without ATP and is released when ATP binds
