Varying crosslinking motifs drive the mesoscale mechanics of actin-microtubule composites

摘要: Abstract The cytoskeleton dynamically tunes its mechanical properties by altering the interactions between semiflexible actin filaments, rigid microtubules, and crosslinking proteins. Here, we use optical tweezers microrheology confocal microscopy to characterize how varying motifs impact microscopic mesoscale mechanics mobility of actin-microtubule composites. We show that, upon subtle changes in pattern, composites separate into two distinct classes force response – primarily elastic versus more viscous behavior. For example, a composite which microtubules are crosslinked each other is markedly than one both filaments but cannot link together. Notably, this distinction only emerges at mesoscopic scales nonlinear forcing, whereas have little on microscale steady-state Our unexpected scale-dependent results not inform physics underlying key processes structures, but, generally, provide valuable perspective materials engineering endeavors focused polymer