Transmembrane electrical potentials in growing maize roots

✍ Scribed by Maurice M. Moloney; Paul-Emile Pilet; Maria-Teresa Marrè; Giulia Romani

• Publisher: Springer-Verlag
• Year: 1982
• Tongue: English
• Weight: 619 KB
• Volume: 156
• Category: Article
• ISSN: 0032-0935
• DOI: 10.1007/bf00393311

✦ Synopsis

The anti-auxin 4-chlorophenoxyisobutyric acid (PCIB) applied at a concentration of l0 -2 tool m -3 to maize root segments was found to induce a transmembrane electrical potential of up to -130 mV (Apd of 30 mV). The kinetics of this response were Comparable to the time scale for PCIB-stimulated H+-extrusion. Both effects are eliminated by the addition of p-fluoromethoxycarbonyl cyanide phenylhydrazone (FCCP). Treatment with fusicoccin (FC) and PCIB together does not result in a hyperpolarization greater than with FC alone. Benzoic acid (10 -2 molm -3) had no effect on the transmembrane electrical potentials. These results are discussed in relation to a possible electrogenic proton pump which may be regulated by perturbations in the cellular auxin content or activity.