Cellular and Molecular Life Sciences CMLS

, Volume 53, Issue 1, pp 69–72

Extracellular Mg2+ regulates intracellular Mg2+ and its subcellular compartmentation in fission yeast, Schizosaccharomyces pombe

  • A. Zhang
  • T. P.-O. Cheng
  • X. Y. Wu
  • B. T. Altura
  • B. M. Altura

DOI: 10.1007/PL00000581

Cite this article as:
Zhang, A., Cheng, TO., Wu, X. et al. CMLS, Cell. mol. life sci. (1997) 53: 69. doi:10.1007/PL00000581

Abstract.

Effects of extracellular magnesium ions ([Mg2+]o ) on intracellular free Mg2+ ([Mg2+]i ) and its subcellular distribution in single fission yeast cells, Schizosaccharomyces pombe, were studied with digital-imaging microscopy and an Mg2+ fluorescent probe (mag-fura-2). Using 0.44 mM [Mg2+]o , [Mg2+]i in yeast cells was 0.91±0.08 mM. Elevation of [Mg2+]o to 1.97 mM induced rapid (within 5 min) increments in [Mg2+]i (2.18±0.11 mM). Lowering [Mg2+]o to 0.06 mM, however, exerted no significant effects on [Mg2+]i (0.93±0.14 mM), at least for periods of up to 30 min. Irrespective of the [Mg2+]o used, the subcellular distribution of [Mg2+]i remained hetero geneous, i.e. where the sub-plasma membrane region >cytoplasm >nucleus. [Mg2+] in all three subcellular compartments increased significantly, two- to threefold, concomitant with [Mg2+]i when placed in 1.97 mM [Mg2+]o . We conclude that [Mg2+]i in fission yeast is maintained at a physiologic level when [Mg2+]o is low, but intracellular free Mg2+ rapidly rises when [Mg2+]o is elevated. Like most eukaryotic cells, yeast may have a Mg2+ transport system(s) which functions to maintain gradients of Mg2+ from the outside to inside the cell and among its subcellular compartments.

Key words. Magnesium; Schizosaccharomyces pombe; mag-fura-2.

Copyright information

© Birkhäuser Verlag Basel, 1997

Authors and Affiliations

  • A. Zhang
    • 1
  • T. P.-O. Cheng
    • 2
  • X. Y. Wu
    • 3
  • B. T. Altura
    • 1
  • B. M. Altura
    • 1
  1. 1.Department of Physiology, State University of New York, Health Science Center at Brooklyn, Brooklyn (New York 11203, USA)US
  2. 2.Department of Anatomy and Cell Biology, State University of New York, Health Science Center at Brooklyn, Brooklyn (New York 11203, USA)US
  3. 3.Department of Microbiology and Immunology, State University of New York, Health Science Center at Brooklyn, Brooklyn (New York 11203, USA)US
  4. 4.Department of Medicine, State University of New York, Health Science Center at Brooklyn, Brooklyn (New York 11203, USA)US
  5. 5.Center for Cardiovascular and Muscle Research, State University of New York, Health Science Center at Brooklyn, Brooklyn (New York 11203, USA)US