Related Experiment Video
Updated: Jun 3, 2026
10:35
Light/dark Transition Test for Mice
Published on: November 13, 2006
Abstract:
Plants reach for the sun by avoiding the shade and by directly growing towards the light. Two studies now suggest that the polar relocation of PIN3, a transporter directing the flow of the plant hormone auxin, drives both growth processes. PIN3 repolarization occurs downstream of shade perception through phytochrome photoreceptors, whereas blue light perceived by phototropin initiates polar recycling of PIN3 and growth towards the light.
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