Open AccessResponse ofSchizosaccharomyces pombeto Zinc Deficiency
Author(s) -
Samantha J. Dainty,
Ciara Kennedy,
Stephen Watt,
Jürg Bähler,
Simon K. Whitehall
Publication year - 2008
Publication title -
eukaryotic cell
Language(s) - English
Resource type - Journals
eISSN - 1535-9778
pISSN - 1535-9786
DOI - 10.1128/ec.00408-07
Subject(s) - schizosaccharomyces pombe , biology , gene , zinc , mutant , gene expression , zinc deficiency (plant disorder) , microarray analysis techniques , messenger rna , regulation of gene expression , transporter , schizosaccharomyces , genetics , microbiology and biotechnology , chemistry , ecology , organic chemistry , nutrient
A component of the cellular response to zinc deficiency operates via control of transcript abundance. Therefore, microarray analysis was employed to identifySchizosaccharomyces pombe genes whose mRNA levels are regulated by intracellular zinc status. A set of 57 genes whose mRNA levels were substantially reduced in response to zinc deficiency was identified, while the mRNA levels of 63 genes were increased by this condition. In order to investigate the mechanisms that control these responses, a genetic screen was employed to identify mutants with defective zinc-responsive gene expression. Two strains (II-1 and V7) that were identified by this screen harbor mutations that are linked tozrt1 + , which encodes a putative Zrt/IRT-like protein (ZIP) zinc uptake transporter. Importantly,zrt1 + mRNA levels are increased in response to zinc deprivation, and cells lacking functional Zrt1 are highly impaired in their ability to proliferate at limiting zinc concentrations. Furthermore,zrt1 null cells were found to have severely reduced zinc contents, indicating that Zrt1 functions as a key regulator of intracellular zinc levels in fission yeast. The deletion offet4 + , another zinc-responsive gene encoding a putative metal ion transporter, exacerbated the phenotypes associated with the loss of Zrt1, suggesting that Fet4 also plays a role in zinc uptake under limiting conditions.