Gravity-induced asymmetric distribution of a plant growth hormone.
H.E. Dolk demonstrated that gravistimulation induced an asymmetric distribution of auxin in a horizontally-placed shoot.  We wish to determine where, and how that asymmetry arises and have demonstrated that the endogenous auxin, indole-3-acetic acid, becomes asymmetrically distributed in the cortical cells of the Zea mays mesocotyl during 3 min of geo-stimulation.  Further, indole-3-acetic acid derived by hydrolysis of an applied transport form of the hormone, indole-3-acetyl-myo-inositol, becomes asymmetrically distributed within 15 min of geo-stimulus time.  From these and prior data we have developed a working theory  that the gravitational stimulus induces a selective leakage, or secretion, of the hormone from the vascular tissue to the cortical cells of the mesocotyl.
Bandurski
R S
RS
Department of Botany and Plant Pathology, Michigan State University, East Lansing 48824, USA.
Schulze
A
A
Momonoki
Y
Y
D001692:Biological Transport / Q000502:physiology; D002849:Chromatography, Gas; D005947:Glucose / Q000493:pharmacokinetics; D006112:Gravitation; D007210:Indoleacetic Acids / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*; D003313:Zea mays / Q000378:metabolism*
D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; C037008:indol-3-ylacetylinositol; C030737:indoleacetic acid; D005947:Glucose