Project description:To further characterize the organization of the transcriptional units and the global behaviour of the genomic island ICEclc in Pseudomonas knackmussii, we have employed Agilent DNA custom microarray in the 8X15K format.
Project description:To support our molecular hypothesis of the effect of rpoS and inrR genes over the activation of the ICEclc genome in Pseudomonas knackmussii B13, we have employed Agilent DNA custom microarray in the 8X15K format. ICEclc-specific gene expression in Pseudomonas knackmussii strain B13 was measured after 48 hours of stationary phase following a growth on 10mM 3-chlorobenzoate (3CBA) as sole carbon and energy source. Various genotypes were tested: wild type (strain nM-BM-078, in 5 replicates), inrR-/- (strain 2201, in triplicates), delta::rpoS (strain 2671, in triplicates).
Project description:To support our molecular hypothesis of the effect of rpoS and inrR genes over the activation of the ICEclc genome in Pseudomonas knackmussii B13, we have employed Agilent DNA custom microarray in the 8X15K format.
Project description:Sensory inputs activate sparse ensembles of neurons in the dentate gyrus of the hippocampus, but how eligibility of individual neurons to recruitment is determined remains elusive. We identified thousands of largely bistable (CpG methylated or unmethylated) regions within neuronal gene bodies, established during mouse dentate gyrus development. Reducing DNA methylation and the proportion of the methylated epialleles at bistable regions compromised novel context-induced neuronal activation. Conversely, increasing methylation and the frequency of the methylated epialleles at bistable regions enhanced intrinsic excitability. Single-nuclei profiling revealed enrichment of specific epialleles from a subset of bistable regions in activated neurons. Genes displaying both differential methylation and expression in activated neurons defined a network of proteins regulating neuronal excitability and structural plasticity. We propose a model in which bistable regions create neuron heterogeneity, and constellations of exonic epialleles dictate, via modulating gene expression and neuronal excitability, eligibility to a coding ensemble
Project description:Dynamic interactions between RhoA and Rac1, members of the Rho small GTPase family, play a vital role in the control of cell migration. Using predictive mathematical modelling and experimental validation in MDA-MB-231 mesenchymal breast cancer cells, we show that Rac1 and RhoA interactions via the PAK-family kinases can produce bistable, switch-like responses to a graded PAK inhibition. Using a small chemical inhibitor of PAK we confirm the model conjecture demonstrating that cellular RhoA and Rac activation levels respond in a bistable manner to PAK inhibition where for a given inhibition level these levels are high or low depending on the history of the system. Consequently, we show that downstream signalling, actin dynamics and cell migration also behave in a bistable fashion, displaying abrupt switches and hysteresis in response to PAK inhibition. In summary, our results demonstrate that PAK is a critical component in the Rac1-RhoA inhibitory crosstalk that mediates bistable GTPase activity and cell migration switches.
