Control of the flow properties of DNA by topoisomerase II and its targeting inhibitor.

摘要: The flow properties of DNA are important for understanding cell division and, indirectly, cancer therapy. DNA topology controlling enzymes such as topoisomerase II thought to play an essential role. We report experiments showing how double-strand passage facilitated by controls rheology. For this purpose, we have measured the elastic storage and viscous loss moduli a model system comprising bacteriophage λ-DNA human IIα using video tracking Brownian motion colloidal probe particles. found that rheology is critically dependent on formation temporal entanglements among molecules with relaxation time ∼1 s. observed effectively removes these transforms solution from physical gel fluid depending consumption ATP. A second aspect study effect generic inhibitor adenylyl-imidodiphosphate (AMP-PNP). In mixtures AMP-PNP ATP, reaction gets blocked progressively fewer relaxed. total replacement ATP results in increase elasticity at higher frequencies, but no transition fixed cross-links.