<u>A theoretical framework for active chiral filaments</u>

The cell cytoskeleton - the active structure that drives cellular motion - is an active chiral fluid. Chirality refers to the breaking of left-right symmetry and can be observed in in-vitro experiments where the kinesin-14 motor walks helically around microtubules with a right-handedness. Here, we develop a framework for coarse graining chiral filament-filament interactions to obtain an active gel theory for living chiral materials. We identify the conditions under which microscopic chirality can be inherited by macro-scales and determine couplings between chiral, extensional, and compressive degrees of freedom in active gels. Our work enables the quantitative understanding of the molecular basis of chiral phenotypes of cellular structures, such as the spindle, and of chiral motions in vitro.