Auxin-regulated cell polarity: an inside job?
Auxin is now known to be a key regulator of polar events in plant cells. The mechanism by which auxin conveys a polar signal to the cell is unknown, but one well-known hypothesis is that the auxin flux across the plasma membrane regulates vesicle trafficking. This hypothesis remains controversial because of its reliance on an as-yet-undiscovered membrane flux sensor. In this article I suggest instead that the polar signal is the auxin gradient within the cell cytoplasm. A computer model of vascular development is presented that demonstrates the plausibility of this scenario. The auxin-binding protein ABP1 might be the receptor for the auxin gradient.
Kramer
Eric M
EM
Physics Department, Bard College at Simon's Rock, Great Barrington, MA 01230, USA. ekramer@simons-rock.edu
D016764:Cell Polarity / Q000502:physiology*; D003593:Cytoplasm / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism*; D008954:Models, Biological; D010940:Plant Proteins / Q000378:metabolism / Q000502:physiology
D007210:Indoleacetic Acids; D010940:Plant Proteins