[SOUND]. In this lecture we're going to cover some important aspects of the LINCS program, and in general in current biology, we will discuss how we are thinking about layers of cellular regulation and the omics technologies which can be used to monitors those layers. When we're thinking about cell regulation, the first thing that comes to mind is the membrane. It's a lipid bilayer that separates the cell from the extracellular environment. Within this lipid bilayer, there are receptors. Those are transmembrane proteins that have extensions that project into the extracellular environment, as well as to the internal of the cell. The extracellular part of those receptors can bind extracellular ligands, or small molecules, that can potentiate the receptors, change their three dimensional conformation, and by doing that, transfer information from the outside of the cell to the inside of the cell. This is called signal transduction. Once the information from the outside was relay to the inside, proteins that bind or dissociate from those receptors can signal to the rest of the cell to change its activity. Ultimately, changes in signaling propagate into the nucleus, where proteins bind or unbind to the DNA to change gene expression. So the nucleus is separated by another membrane, the nuclear membrane, and within it the DNA exists in chromatin. The DNA gives rise to mRNA, that then is translated to protein. So proteins leave the cytoplasm, enter the nucleus, and bind to the DNA. Those proteins are called transcription factors which bind to the DNA, they change the expression level of genes, producing more or less mRNA in a process called transcription. The mRNA that is transcribed, exists the nucleus and becomes translated into proteins in the ribosomes, in a process called protein synthesis. We now have the technologies to monitor the different parts of the cell using various omics technologies. This include transcriptomics to measure gene expression at the mRNA level. Genomics that allows the sequencing the DNA, or the variants within the DNA, across individuals and in cancer, where mutations, insertions, deletions and copy number variations can be detected. At the cell signaling level, we can measure protein expression, phosphoproteins, which are proteins that have post translation modifications, these are the result of the cell signaling processes. We can also measure the level of metabolites within the cell using technologies that are called metabolomics. So proteomics measure protein levels; metabolomics measure metabolites, genomics are referred to, typically, the sequencing of the DNA, and transcriptomics the measure of the levels of mRNA. We also have epigenomics, which are technologies that allow us to understand the chromatin structure and the occupancy of proteins on the DNA. Those technologies include, for example, ChIP-Seq and histone modification profiling, and the GCP experiments that are done at the Broad Institute for LINCS, are part of this types of omics. We can also measure cytokines at the extracellular space to find out what the cell is exposed to, and how after potentiation, the cell changes the extra cellular environment by secreting proteins to signal to other cells. Once cells are stimulated with various ligands, and signaling is initiated, typically the ultimate outcome is a change in cell phenotype. For example, cells die, increasing in proliferation, differentiate, or de-differentiate. Those processes are typically monitored by imaging of cell phenotype. We now have the capability to measure cell phenotype through imaging in high throughput after many types of perturbations using robotics. So to overview and summarize, we think about cellular regulation at various layers. Starting from the extracellular environment through the membrane, through the cytosol, where cell signaling and signal transduction take place, through regulation of gene expression in the nucleus, and those are the gene regulatory networks that we can reconstruct, and then the important processes of transcription and translation, gives us an overview of cell regulations that can be obtained using those various omics technologies. Our goal in LINCS is to combine data across regulatory layers, measured using those omics technologies to better understand cellular regulation at a global scale. [MUSIC]