Open AccessIdentification of direct and indirect targets of the Gln3 and Gat1 activators by transcriptional profiling in response to nitrogen availability in the short and long term
Author(s) -
Scherens Bart,
Feller André,
Vierendeels Fabienne,
Messenguy Francine,
Dubois Evelyne
Publication year - 2006
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.1567-1364.2006.00060.x
Subject(s) - biology , gene , permease , gata transcription factor , gene expression , glutamine synthetase , gene expression profiling , psychological repression , biochemistry , regulation of gene expression , microarray analysis techniques , genetics , glutamine , promoter , transporter , amino acid
Nitrogen catabolite repression (NCR) consists in the specific inhibition of transcriptional activation of genes encoding the permeases and catabolic enzymes needed to degrade poor nitrogen sources. Under nitrogen limitation or rapamycin treatment, NCR genes are activated by Gln3 or Gat1, or by both factors. To compare the sets of genes responding to rapamycin or to nitrogen limitation, we used DNA microarrays to establishing the expression profiles of a wild type strain, and of a double gln3 Δ –gat1 Δ strain, grown on glutamine, after addition of rapamycin, on proline, or after a shift from glutamine to proline. Analysis of microarray data revealed 392 genes whose expression was dependent on the nitrogen source quality. 91 genes were activated in a GATA factor‐dependent manner in all growth conditions, suggesting a direct role of Gln3 and Gat1 in their expression. Other genes were only transiently up‐regulated (stress‐responsive genes) or down‐regulated (genes encoding ribosomal proteins and translational factors) upon nitrogen limitation, and this regulation was delayed in a gln3 Δ –gat1 Δ strain. Repression of amino acid and nucleotide biosynthetic genes after a nitrogen shift did not depend on Gcn4. Several transporter genes were repressed as a consequence of enhanced levels of NCR‐responsive permeases present at the plasma membrane.