Monastrol is a cell-permeable small molecule inhibitor discovered by Thomas U. Mayer in the lab of Tim Mitchison

Tim Mitchison

Professor Timothy John "Tim" Mitchison, PhD, FRS is a British systems biologist. He is Hasib Sabbagh Professor of Systems Biology at Harvard University in the United States.- Biography :...

. Monastrol was shown to inhibit the kinesin

Kinesin

A kinesin is a protein belonging to a class of motor proteins found in eukaryotic cells. Kinesins move along microtubule filaments, and are powered by the hydrolysis of ATP . The active movement of kinesins supports several cellular functions including mitosis, meiosis and transport of cellular...

 Eg5, a motor protein important for spindle bipolarity.

Mechanism of action

Monastrol binds to a long loop that is specific to the Eg5 kinesin family, and allosterically inhibits ATPase activity of the kinesin