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. 1985 Nov;79(3):771–776. doi: 10.1104/pp.79.3.771

Potassium Transport in Corn Roots 1

IV. Characterization of the Linear Component

Leon V Kochian 1, Jiao Xin-Zhi 1,2, William J Lucas 1
PMCID: PMC1074969  PMID: 16664490

Abstract

A detailed examination was conducted on the linear, or first-order kinetic component for K+(86Rb+) influx into root segments of both low- and high-salt grown corn seedlings (Zea mays [A632 × Oh 43]). In tissue from both low- and high-salt grown roots, replacement of Cl− in the uptake solution by either SO42−, H2PO4−, or NO3− caused a significant (50-60%) and specific inhibition of the linear component of K+ influx. The anion transport inhibitor, 4,4′-diisothiocyano-2,2′-disulfonic acid, was found to abolish saturable Cl− influx in corn roots while causing a significant (50-60%) and specific inhibition of the linear K+ uptake system; this inhibition was identical to that observed when Cl− was replaced by other anions in the K+ uptake solution. Additionally, the quaternary ammonium cation, tetraethylammonium, which has been shown to block K+ channels in nerve axons, also caused a dramatic (70%) and specific inhibition of the linear component of K+ influx, but this was obtained only in high-salt roots. The reasons for this difference are discussed with respect to the differing abilities of low- and high-salt roots to absorb tetraethylammonium.

Our present results indicate that the linear component of K+ influx may occur by a passive process involving transmembrane K+ channels. Fluxes through these K+ channels may be partly coupled to a saturating Cl− influx mechanism.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Armstrong C. M. Inactivation of the potassium conductance and related phenomena caused by quaternary ammonium ion injection in squid axons. J Gen Physiol. 1969 Nov;54(5):553–575. doi: 10.1085/jgp.54.5.553. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bennett A. B., Spanswick R. M. Derepression of amino Acid-h cotransport in developing soybean embryos. Plant Physiol. 1983 Jul;72(3):781–786. doi: 10.1104/pp.72.3.781. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Cheeseman J. M., Hanson J. B. Energy-linked Potassium Influx as Related to Cell Potential in Corn Roots. Plant Physiol. 1979 Nov;64(5):842–845. doi: 10.1104/pp.64.5.842. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Cheeseman J. M., Hanson J. B. Mathematical analysis of the dependence of cell potential on external potassium in corn roots. Plant Physiol. 1979 Jan;63(1):1–4. doi: 10.1104/pp.63.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Cheeseman J. M., Lafayette P. R., Gronewald J. W., Hanson J. B. Effect of ATPase inhibitors on cell potential and k influx in corn roots. Plant Physiol. 1980 Jun;65(6):1139–1145. doi: 10.1104/pp.65.6.1139. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Christensen H. N., Liang M. On the nature of the "non-saturable" migration of amino acids into Ehrlich cells and into rat jejunum. Bibl Laeger. 1966 Mar 14;112(3):524–531. doi: 10.1016/0926-6585(66)90255-x. [DOI] [PubMed] [Google Scholar]
  7. Cohen S. R. A comparison of the rate equations, kinetic parameters, and activation energies for the initial uptake of L-lysine, L-valine, gamma-aminobutyric acid, and alpha-aminoisobutyric acid by mouse brain slices. J Membr Biol. 1975 Jun 3;22(1):53–72. doi: 10.1007/BF01868163. [DOI] [PubMed] [Google Scholar]
  8. Epstein E., Rains D. W., Elzam O. E. RESOLUTION OF DUAL MECHANISMS OF POTASSIUM ABSORPTION BY BARLEY ROOTS. Proc Natl Acad Sci U S A. 1963 May;49(5):684–692. doi: 10.1073/pnas.49.5.684. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Jackson W. A., Flesher D., Hageman R. H. Nitrate Uptake by Dark-grown Corn Seedlings: Some Characteristics of Apparent Induction. Plant Physiol. 1973 Jan;51(1):120–127. doi: 10.1104/pp.51.1.120. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Keifer D. W., Franceschi V. R., Lucas W. J. Plasmalemma Chloride Transport in Chara corallina: Inhibition by 4,4'-Diisothiocyano-2,2'-Disulfonic Acid Stilbene. Plant Physiol. 1982 Nov;70(5):1327–1334. doi: 10.1104/pp.70.5.1327. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Keifer D. W., Lucas W. J. Potassium Channels in Chara corallina: CONTROL AND INTERACTION WITH THE ELECTROGENIC H PUMP. Plant Physiol. 1982 Apr;69(4):781–788. doi: 10.1104/pp.69.4.781. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Kochian L. V., Lucas W. J. Potassium Transport in Corn Roots : II. The Significance of the Root Periphery. Plant Physiol. 1983 Oct;73(2):208–215. doi: 10.1104/pp.73.2.208. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Kochian L. V., Lucas W. J. Potassium transport in corn roots : I. Resolution of kinetics into a saturable and linear component. Plant Physiol. 1982 Dec;70(6):1723–1731. doi: 10.1104/pp.70.6.1723. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Lichtner F. T., Spanswick R. M. Sucrose uptake by developing soybean cotyledons. Plant Physiol. 1981 Sep;68(3):693–698. doi: 10.1104/pp.68.3.693. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Lin W. Inhibition of anion transport in corn root protoplasts. Plant Physiol. 1981 Aug;68(2):435–438. doi: 10.1104/pp.68.2.435. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Lowendorf H. S., Slayman C. L., Slayman C. W. Phosphate transport in Neurospora. Kinetic characterization of a constitutive, low-affinity transport system. Biochim Biophys Acta. 1974 Dec 24;373(3):369–382. doi: 10.1016/0005-2736(74)90017-0. [DOI] [PubMed] [Google Scholar]
  17. Lucas W. J. HCO(3) Influx across the Plasmalemma of Chara corallina: Physiological and Biophysical Influence of 10 mm K. Plant Physiol. 1978 Apr;61(4):487–493. doi: 10.1104/pp.61.4.487. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Maynard J. W., Lucas W. J. A Reanalysis of the Two-Component Phloem Loading System in Beta vulgaris. Plant Physiol. 1982 Mar;69(3):734–739. doi: 10.1104/pp.69.3.734. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Maynard J. W., Lucas W. J. Sucrose and Glucose Uptake into Beta vulgaris Leaf Tissues : A Case for General (Apoplastic) Retrieval Systems. Plant Physiol. 1982 Nov;70(5):1436–1443. doi: 10.1104/pp.70.5.1436. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Pitman M. G. Active H Efflux from Cells of Low-salt Barley Roots during Salt Accumulation. Plant Physiol. 1970 Jun;45(6):787–790. doi: 10.1104/pp.45.6.787. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Rhoads D. B., Waters F. B., Epstein W. Cation transport in Escherichia coli. VIII. Potassium transport mutants. J Gen Physiol. 1976 Mar;67(3):325–341. doi: 10.1085/jgp.67.3.325. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Scarborough G. A. Sugar transport in Neurospora crassa. II. A second glucose transport system. J Biol Chem. 1970 Aug 10;245(15):3985–3987. [PubMed] [Google Scholar]

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