Gln3 is a main regulator of nitrogen assimilation in Candida glabrata.
Microbiology. 2016 May 24;
Authors: Pérez-delosSantos FJ, Riego-Ruiz L
After Candida albicans, the yeast Candida glabrata ranks second as an aetiological agent of candidaemia and is the most frequently encountered non-C. albicans species in patients with invasive candidiasis. Transcriptome analysis in C. albicans, C. glabrata and Cryptoccocus neoformans has revealed that, when engulfed by macrophages, these yeasts upregulate genes involved in nutrient acquisition including nitrogen transporters such as the general amino acid permease GAP1, the dicarboxylic amino acid permease DIP5, the basic amino acid permease CAN1 and the ammonium permeases MEP1 and MEP2. Nitrogen assimilation has been well studied in model fungi species such as Aspergillus nidulans, Neurospora crassa and Saccharomyces cerevisiae. However, little is known about nitrogen assimilation in C. glabrata. In the present study we report the major role of Gln3 in the assimilation of glutamine, ammonium and proline. Ure2 has also a role in nitrogen assimilation but it is only observable in ammonium and glutamine. In addition, Gat1 has a minor role that is only observable in the absence of Ure2 and Gln3. Gln3 is absolutely necessary for full ammonium uptake from the media. We also show that C. glabrata MEP2 gene expression is completely dependent on Gln3 whereas, GAP1 regulation is mainly exerted by Gln3 with the exception of proline where Gat1 has a minor role. In addition, Ure2 seems to be a negative regulator of these NCR-sensitive genes in C. glabrata, similar to what has been described in S. cerevisiae. Our data, places Gln3 as a key regulator of nitrogen assimilation in C. glabrata.
PMID: 27222014 [PubMed - as supplied by publisher]