Unveiling the Giant Proteins Behind the World's Fastest Biological Movement.
Chinese scientists have discovered the molecular basis for the ultrafast contraction of Spirostomum, a genus of millimeter-scale single-celled protists known for their incredibly rapid movement, using a high-quality genome obtained from RNAi. The contractile structure was found to be composed of two giant proteins and two Ca2+ binding proteins, providing a blueprint for the design and construction of ultrafast contractile micromachines. This study is significant for understanding the molecular mechanism of ultrafast cell contraction.