The Influence of Light on Microtubule Dynamics and Alignment in the Arabidopsis Hypocotyl

摘要: Light and dark have antagonistic effects on shoot elongation, but little is known about how these are translated into changes of shape. Here we provide genetic evidence that the light/gibberellin‐signaling pathway affects properties microtubules required to reorient growth. To follow microtubule dynamics for hours without triggering photomorphogenic inhibition growth, used Arabidopsis thaliana light mutants in gibberellic acid/DELLA pathway. Particle velocimetry was map mass movement plus ends, providing new insight way switch between orthogonal axes upon onset Longitudinal signal growth cessation, observed cells also self-organize a strikingly bipolarized longitudinal array before bursts This gives radial star that, far from being random array, seems be key transitional step transverse forecasting faster elongation follows. Computational modeling provides mechanistic transitions. In faster-growing mutants, were found polymerization rates undergo reorientations. suggests mechanism which light-signaling modifies their ability axes.