MYOSIN HEADS ARE DANCIN’
by Arthur W. Siebens, Ph.D., Copyright 2003
to the tune of “Dancin’ in the Street,” by Marvin Gaye, Ivy Hunter and William Stevenson

An action potential moves down a motor neuron
Acetyl choline's let loose
It diffuses to receptors on the muscle cell membrane (the sarcolemma)
A second action potential’s induced
T (transverse) tubules spread the impulse
The SR (sarcoplasmic reticulum) kicks in, yeah
Calcium’s released
All you need is calcium, sweet calcium
Calcium everywhere
Calcium binds to troponin, which shifts tropomyosin
So myosin heads (Hint: think my head) can bind, Oh—
CHORUS
When myosin heads bind to actin filaments fine (actin thin, myosin thick)
Those tiny heads relax
Actin slides, pushed by myosin head strides
As those heads relax, that muscle contracts!
Those heads are dancin’
With tiny little beats (~5/sec)
Now there’s a transformation
In myosin’s configuration
Brought about by ATP
After ATP binds, 1) it hydrolyzes
(note: numbers correspond to steps in Fig. 49.28, Campbell, Reece, Mitchell, Biology, 1999)
Cocks that myosin head with high energy
2) There’s cross bridge formation
3) Release of ADP (and Pi), yeah
That myosin head relaxes
And there’s movement, sweet movement
That’s why that muscle’s there
4) Then a new ATP binds, the head releases to find
A new actin site, then it all repeats, yeah
CHORUS
Myosin heads are dancin’
Driven by ATP
Driven by ATP, yeah
Driven by ATP, yeah...