Highly efficient photocontrol of mitotic kinesin Eg5 ATPase activity using a novel photochromic compound composed of two azobenzene derivatives

Abstract

Mitotic kinesin Eg5 plays an important physiological role in cell division. Several small-molecule inhibitors of Eg5 are the focus of cancer therapies. Azobenzene is a photochromic compound exhibiting cis-trans isomerization upon ultraviolet (UV) and visible (VIS) light irradiation. Photochromic compounds of azobenzene derivatives, mimicking Eg5-specific inhibitors of STLC, indicated photoreversible inhibitory effects on Eg5 ATPase activity; however, the photoreversible switching efficiency was not significant. This study presents a novel synthesized photochromic Eg5 inhibitor 2, 3-bis[(2,5-dioxo-1-{4-[(E)-2-phenyldiazen-1-yl]phenyl}pyrrolidin-3-yl)sulfanyl] butanedioic acid (BDPSB), which is composed of two azobenzenes. BDPSB exhibited cis-trans isomerization with UV and VIS light irradiation. The trans form of BDPSB significantly inhibited microtubule-dependent ATPase activity of Eg5, with an IC50 of 74 μM. Cis BDPSB showed weak effects on the microtubule-dependent ATPase activity. The results suggest that the novel photochromic Eg5 inhibitor BDPSB, which exhibits highly efficient photoswitching, shows a switch 'ON' and 'OFF' behaviour with VIS and UV light irradiation.

High-resolution imaging reveals how the spindle midzone impacts chromosome movement

“…Therefore, kinesin-5 inhibition effects may be revealed only if the initial phase of relative sliding is blocked. Photo-switchable chemical probes ( Sadakane et al, 2018 ) or similar faster-acting inhibition strategies are needed to properly dissect the role of kinesin-5 in anaphase microtubule sliding. In vitro, ensembles of kinesin-5 can resist filament sliding, and the magnitude of this resistance scales with the number of motors and length of microtubule overlap ( Shimamoto et al, 2015 ).…”

High kinesin family member 11 expression predicts poor prognosis in patients with clear cell renal cell carcinoma

“…Kinesin inhibitors have been shown to exhibit strong antitumour activities38 39 with many clinical studies of kinesin inhibitors ongoing. In our study, SB743921 was selected as a Kif11 inhibitor with the inhibition of the ATPase activities of Kif11 21 40.…”

Optical Control of Mitosis with a Photoswitchable Eg5 Inhibitor

“…The Tamaoki group introduced one of the first photoswitchable inhibitors of a motor protein for the mitotic kinesin CENP‐E, which was based on the small molecule GSK923295 [37, 38] . Recently, Maruta and colleagues introduced photoswitchable inhibitors that enabled reversible control of Eg5 in vitro [39–41] . However, they did not demonstrate activity in cells, possibly due to insufficient cell permeability and solubility of their compounds.…”

“…[37,38] Recently, Maruta and colleagues introduced photoswitchable inhibitors that enabled reversible control of Eg5 in vitro. [39][40][41] However, they did not demonstrate activity in cells, possibly due to insufficient cell permeability and solubility of their compounds. This led us to synthesize and evaluate azobenzenebased photoswitchable Eg5 inhibitors.…”