BTB-1

Research use only, not for human use.

BTB-1 is a novel small molecule inhibitor of the mitotic motor protein Kif18A.

BTB-1 is a novel small molecule inhibitor of the mitotic motor protein Kif18A, which was identified by Catarinella et al. during a highthroughput screen against Kif18A ’s MT-stimulated ATPase activity, with an IC50 of 1.7 –1.9 M . It is selective within the kinesin subgroup of Kif4, Eg5, MKLP-1, MKLP-2, MPP1, CENP-E and MCAK, and during in vitro motility assays Kif18A ’s MT gliding ability was blocked by the addition of BTB-1 in a reversible manner. BTB-1 was found to be ATP competitive and MT uncompetitive, only inhibiting the ATPase activity of the MT-bound motor protein. BTB-1 could serve as a valuable tool in disentangling the nature of Kif18A ’s double functionality within mitosis and assessing for potential therapeutic utilities.

BTB-1 blocks the motility of Kif18A in a reversible manner. BTB-1 inhibits Kif18A in an adenosine triphosphate (ATP)-competitive but microtubule-uncompetitive manner and slows down the progression of cells through mitosis. 100 μM BTB-1 does not significantly inhibit any of the other tested mitotic kinesins. BTB-1 competes with ATP for Kif18A binding only when the motor-protein is associated with its pseudosubstrate microtubules. HeLa cells treated with BTB-1 accumulate in mitosis in a dose-dependent manner. BTB-1 shows cell toxicity with an EC50 values of 35.8 μM. HeLa cells treated with 50 μM BTB-1 reveals severe defects in spindle morphology and chromosome alignment. Treatment with high concentrations of BTB-1 does not result in elongated spindles.

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BTB1 | BTB 1 | BTB-1

Others

Other Targets

mitotic kinesin Kif18A

Cancer

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86030-08-2

297.71

C12H8ClNO4S

>98% (HPLC)

DMSO : ≥ 100 mg/mL; 335.90 mM

O=S(=O)(c1ccc(Cl)cc1[N+](=O)[O-])c1ccccc1

4-chloro-2-nitro-1-(phenylsulfonyl)benzene

(-20℃)

With Ice Pack

≥ 2 years