Researchers from the University of British Columbia (UBC) have discovered an
internal messaging system that plants use to manage the growth and division
of their cells.
The research team, led by UBC botany professor Geoffrey Wasteneys discovered
that the system is driven by a protein called CLASP. It is found in plants,
animals, and fungi, and plays an essential role in cell growth and division
by coordinating the assembly of filaments within cells. Its gene in plants
was first identified by Wasteneys in 2007.
The production of CLASP is reduced by a plant-growth hormone called
brassinosteroid. The research team exposed thale cress to brassinosteroid
and found that the exposure stunted the plants in a way that closely
resembled mutant versions of the plant that lacked the CLASP protein
The researchers also discovered that CLASP prevents the degradation of
brassinosteroid receptors. When CLASP is scarce, brassinosteroid becomes
less effective, resulting in CLASP levels rising again. Essentially, the
protein and the hormone affect each other in a negative-feedback loop.