Regulation of Trk-dependent potassium transport by the calcineurin pathway involves the Hal5 kinase

FEBS Lett. 2010 Jun 3;584(11):2415-20. doi: 10.1016/j.febslet.2010.04.042. Epub 2010 Apr 20.

Abstract

The phosphatase calcineurin and the kinases Hal4/Hal5 regulate high-affinity potassium uptake in Saccharomyces cerevisiae through the Trk1 transporter. We demonstrate that calcineurin is necessary for high-affinity potassium uptake even in the absence of Na(+) stress. HAL5 expression is induced in response to stress in a calcineurin-dependent manner through a newly identified functional CDRE (nt -195/-189). Lack of calcineurin decreases Hal5 protein levels, although with little effect on Trk1 amounts. However, the growth defect of cnb1 cells at K(+)-limiting conditions can be rescued in part by overexpression of HAL5, and this mutation further aggravates the potassium requirements of a hal4 strain. This suggests that the control exerted by calcineurin on Hal5 expression may be biologically relevant for Trk1 regulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Transport / genetics
  • Calcineurin / metabolism*
  • Ion Transport / genetics
  • Ions / metabolism
  • Membrane Transport Proteins / metabolism*
  • Mutation
  • Potassium / metabolism*
  • Protein Kinases / metabolism*
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Ions
  • Membrane Transport Proteins
  • Saccharomyces cerevisiae Proteins
  • Protein Kinases
  • Hal5 protein, S cerevisiae
  • Calcineurin
  • Potassium