Transcription profiling of Dictyostelium discoideum grown for a short time or exponentially on axenic culture medium or bacteria

ABSTRACT: Dictyostelium amoebae feed on bacteria, which are taken up by phagocytosis. Using DNA microarrays we have investigated gene expression during phagocytosis of Dictyostelium cells incubated with Escherichia coli. The gene expression profiles of cells incubated for a short time with bacteria were compared with cells either exposed to axenic culture medium or exponentially growing on bacteria. Transcriptional changes during exponential growth either in axenic medium or on bacteria were also compared, in order to identify genes differentially expressed during growth on bacteria. We recognized 443 and 59 genes, which are differentially regulated by phagocytosis or growth on bacteria, respectively, and 102 genes, which are common to both processes. Roughly one third of the genes is up- and two third down-regulated compared to growth in axenic medium. Functional annotation of differentially regulated genes revealed that phagocytosis induces profound changes in carbohydrate, aminoacid and lipid metabolism, in the translation machinery and in cytoskeletal components. Among the up-regulated genes are genes encoding proteins involved in transcription and translation, sterol metabolism and mitochondrial biogenesis. Very few changes were detected in genes required for endocytosis and intracellular traffic, suggesting that the intracellular traffic machinery is mostly in common between phagocytosis and pinocytosis. A few putative receptor or adhesion proteins and components of signal transduction have been identified, which could be involved in regulating phagocytosis.

ORGANISM(S): Dictyostelium discoideum

SUBMITTER: Gareth Bloomfield 

PROVIDER: E-TABM-415 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress