Modulation of cellular transcriptome and proteome composition by azidohomoalanine —implications on click chemistry–based secretome analysis

AbstractThe analysis of the secretome provides important information on proteins defining intercellular communication and the recruitment and behavior of cells in specific tissues. Especially in the context of tumors, secretome data can support decisions for diagnosis and therapy. The mass spectrometry –based analysis of cell-conditioned media is widely used for the unbiased characterization of cancer secretomes in vitro. Metabolic labeling using azide-containing amino acid analogs in combination with click chemistry facilitates this type of analysis in the presence of serum, preventing serum st arvation-induced effects. The modified amino acid analogs, however, are less efficiently incorporated into newly synthesized proteins and may perturb protein folding. Combining transcriptome and proteome analysis, we elucidate in detail the effects of metabolic labeling with the methionine analog az idohomoalanine (AHA) on gene and protein expression. Our data reveal that 15–39% of the proteins detected in the secretome displayed changes in transcript and protein expression induced by AHA labeling. Gene Ontology (GO) analyses indicate that metabolic labeling using AHA leads to induction of ce llular stress and apoptosis-related pathways and provide first insights on how this affects the composition of the secretome on a global scale.Key messagesAzide-containing amino acid analogs affect gene expression profiles.Azide-containing amino acid analogs influence cellular proteome.Azidoh...
Source: Journal of Molecular Medicine - Category: Molecular Biology Source Type: research