RACK1/Asc1p, a ribosomal node in cellular signaling.
RACK1/Asc1p and its essential orthologues in higher eukaryotes, such as RACK1 in metazoa, are involved in several distinct cellular signaling processes. The implications of a total deletion have never been assessed in a comprehensive manner. This study reveals the major cellular processes affected in a Saccharomyces cerevisiae Δasc1 deletion background via de novo proteome and transcriptome analysis, as well as subsequent phenotypical characterizations. The deletion of ASC1 reduces iron uptake and causes nitrosative stress, both known indicators for hypoxia, which manifests in a shift of energy metabolism from respiration to fermentation in the Δasc1 strain. Asc1p further impacts cellular metabolism through its regulative role in the MAP kinase signal transduction pathways of invasive/filamentous growth and cell wall integrity. In the Δasc1 mutant strain, aberrations from the expected cellular response, mediated by these pathways, can be observed and are linked to changes in protein abundances of pathway-targeted transcription factors. Evidence of the translational regulation of such transcription factors suggests that ribosomal Asc1p is involved in signal transduction pathways and controls the biosynthesis of the respective final transcriptional regulators.
Institute of Microbiology and Genetics, Georg-August Universität, D-37077 Göttingen, Germany.
Nicole
N
Rachfall
Kerstin
K
Schmitt
Susanne
S
Bandau
Nadine
N
Smolinski
Armin
A
Ehrenreich
Oliver
O
Valerius
Gerhard H
GH
Braus
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport; D004734:Energy Metabolism; D005285:Fermentation / Q000235:genetics; D017353:Gene Deletion; D020869:Gene Expression Profiling; D007501:Iron / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000235:genetics; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010101:Oxygen Consumption; D010455:Peptides / Q000235:genetics* / Q000378:metabolism*; D000075370:Receptors for Activated C Kinase; D012270:Ribosomes / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D059467:Transcriptome
D048868:Adaptor Proteins, Signal Transducing; D010455:Peptides; D000075370:Receptors for Activated C Kinase; D029701:Saccharomyces cerevisiae Proteins; C070301:peptide I; D007501:Iron; D020928:Mitogen-Activated Protein Kinases