For a body part engaged in an ongoing tug-of-war, it really is fitting that it resembles a rope. The interplay of two muscle fibres instrumental in turning energy into movement are mirrored in this fairground sport. Actin plays the role of the rope while myosin acts as the eager hands looking to drag the opponent backwards. With the addition of energy, little levers on the myosin strands move forwards and backwards. Slotting ratchet-like into slots along the length of the neighbouring actin string, this pulls the fibres together and causes the muscle to contract. In this live zebrafish embryo's tail, the hair-thin actin filaments (in black) can be seen running parallel to the chunky myosin giving off a florescent blue. To dive deeper into this process, researchers used new techniques to isolate a single myosin strand and in doing so, dragged one more of nature's secrets into the light.
Written by Jan Piotrowski
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