Galactose inhibits auxin-induced growth of Avena coleoptiles by two mechanisms.
Galactose inhibits auxin-induced growth of Avena coleoptiles by at least two mechanisms.  First, it inhibits auxin-induced H(+)-excretion needed for the initiation of rapid elongation.  Galactose cannot be doing so by directly interfering with the ATPase since fusicoccin-induced H(+)-excretion is not affected.  Secondly, galactose inhibits long-term auxin-induced growth, even in an acidic (pH 4.5) solution.  This may be due to an inhibition of cell wall synthesis.  However, galactose does not reduce the capacity of walls to be loosened by H+, given exogenously or excreted in response to fusicoccin.
Cheung
S P
SP
Department of Botany, University of Washington, Seattle 98195.
Cleland
R E
RE
D018554:Avena / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology; D018548:Cotyledon / Q000187:drug effects / Q000254:growth & development* / Q000502:physiology; D004347:Drug Interactions; D005690:Galactose / Q000494:pharmacology*; D006027:Glycosides / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007210:Indoleacetic Acids / Q000494:pharmacology*; D010937:Plant Growth Regulators / Q000494:pharmacology; D011522:Protons; D013997:Time Factors
D006027:Glycosides; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D011522:Protons; C007808:fusicoccin; C030737:indoleacetic acid; D005690:Galactose