Open AccessProtein Phosphatase 2B of Saccharomyces Cerevisiae is Required for Tolerance to Manganese, in Blocking the Entry of ions into the Cells
Author(s) -
Farcasanu Ileana C.,
Hirata Dai,
Tsuchiya Eiko,
Nishiyama Fumitaka,
Miyakawa Tokichi
Publication year - 1995
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1995.0712a.x
Subject(s) - divalent , manganese , mutant , phosphatase , chemistry , saccharomyces cerevisiae , calcineurin , wild type , biochemistry , biophysics , enzyme , biology , yeast , gene , medicine , surgery , organic chemistry , transplantation
The role of protein phosphatase 2B (PP2B/calcineurin) of Saccharomyces cerevisiae in the tolerance to divalent cations was investigated. PP2B‐deficient mutants were found to be sensitive to MnCl 2 , but not to ZnCl 2 , CuCl 2 , NiCl 2 , and CoCl 2 . By measuring both manganese uptake and its efflux, it was found that the sensitivity of the mutant cells was due to an increase in manganese uptake and that the wild‐type cells were able to prevent manganese entry into the cells, rather than export it in a more efficient manner. In the presence of the immunosuppressant FK506, the behavior of wild‐type cells became similar to that of PP2B mutants. Out of various divalent cations tested, externally added magnesium ions were able to block manganese uptake in both wild‐type and PP2B mutant strains.