Project description:In response to starvation, Myxococcus xanthus initiates a developmental program that results in the formation of spore-filled multicellular fruiting bodies. Here we have used cDNA microarray analysis to determine changes in the global gene expression at different time points of the developmental process. The expression of nearly 900 genes was found to be altered at least two-fold during development as compared to vegetative cells. Genes encoding proteins with typical vegetative functions such as protein synthesis and energy metabolism were transcriptionally down-regulated in the early stages of development. Among the 430 genes transcriptionally up-regulated during development genes with regulatory functions were overrepresented; underlining that fruiting body formation relies on a complex signalling network. Notably, almost 40% of all genes with increased expression at different stages of development encoded hypothetical proteins indicating a large unexplored potential of proteins important for fruiting body formation. Keywords: Time course of development with 9 time points
Project description:In Myxococcus xanthus 55% of the more than 250 two-component signal transduction systems (TCS) genes are orphan. We hypothesized that the histidine kinase SgmT and the response regulator DigR, which comprises a DNA binding domain of the HTH_Xer type, function together to regulate gene expression. We performed genome-wide expression profiling experiments to determine wether the same set of genes are differentially expressed in the ΔdigR and ΔsgmT mutants.
Project description:Myxococcus xanthus is a model organism for studying social behaviors and cell differentiation in bacteria. Upon nutrient depletion, M. xanthus cells initiate a developmental program that culminates in formation of spore-filled fruiting bodies and peripheral rods outside of fruiting bodies. Completion of this developmental program depends on fine-tuned spatial and temporal regulation of gene expression, intercellular communication, signaling by nucleotide-based second messengers, and motility. In order to understand stage-specific gene expression during growth and development, we extracted total RNA from vegetative cells (referred as 0 h of development) and from cells developed for 6, 12, 18 and 24 h under submerged conditions in two replicates.
