Open AccessThe wheat MAP kinase phosphatase 1 confers higher lithium tolerance in yeast
Author(s) -
Zaidi Ikram,
González Asier,
Touzri Majdi,
Alvarez María C.,
Ramos José,
Masmoudi Khaled,
Ariño Joaquín,
Hanin Moez
Publication year - 2012
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/j.1567-1364.2012.00827.x
Subject(s) - phosphatase , biology , saccharomyces cerevisiae , yeast , biochemistry , kinase , galactose , lithium (medication) , alkaline phosphatase , protein kinase a , enzyme , endocrinology
The durum wheat TMKP 1 gene encodes a MAP kinase phosphatase. When overexpressed in S accharomyces cerevisiae , TMKP 1 leads to salt stress tolerance (especially LiCl ), which is dependent on the phosphatase activity of the protein. The TMKP 1‐associated Li + resistance is restricted to a galactose‐containing medium. Interestingly, this salt tolerance is abolished in the absence of one member of the yeast type 2 C S er/ T hr protein phosphatase family ( P tc1) but not when other members such as P tc2 or P tc3 are lacking. Increased Li + tolerance is not mediated by regulation of the P ‐type ATP ase E na1, a major determinant for salt tolerance. In contrast, the effect of TMKP 1 depends on H al3 (a negative regulator of P pz phosphatases) and on the presence of the high‐affinity potassium transporters T rk1/ T rk2. Tolerance to Li + is also abolished in cells lacking the aldose reductase G re3, previously shown to be involved in the resistance to this cation. This study provides evidence that the wheat TMKP 1 phosphatase is contributing to reduce the exacerbated lithium toxicity in galactose‐grown cells, in a way that depends on the presence of the potassium T rk transporters.