* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download BIO 330 Cell Biology Lecture Outline Spring 2011 Chapter 14
Western blot wikipedia , lookup
Vectors in gene therapy wikipedia , lookup
Polyclonal B cell response wikipedia , lookup
Gene regulatory network wikipedia , lookup
Transcriptional regulation wikipedia , lookup
Proteolysis wikipedia , lookup
Two-hybrid screening wikipedia , lookup
Secreted frizzled-related protein 1 wikipedia , lookup
Mitogen-activated protein kinase wikipedia , lookup
Ultrasensitivity wikipedia , lookup
NMDA receptor wikipedia , lookup
Ligand binding assay wikipedia , lookup
Lipid signaling wikipedia , lookup
Endocannabinoid system wikipedia , lookup
Molecular neuroscience wikipedia , lookup
Clinical neurochemistry wikipedia , lookup
Biochemical cascade wikipedia , lookup
G protein–coupled receptor wikipedia , lookup
BIO 330 Cell Biology Lecture Outline Spring 2011 Chapter 14: Signal Transduction – Messengers and Receptors I. Overview of Chemical Signals and Receptors A. Types of chemical signals Endocrine Paracrine Juxtacrine Autocrine B. Receptors Ligands Second messengers Signal transduction Membrane vs. intracellular receptors Peptide vs. hydrophobic ligands C. Binding between receptors and ligands Ligands bind their cognate receptors at the binding site Receptor is “occupied” when ligand is bound Amount of receptor binding is proportional to concentration of free ligand Similar to enzyme kinetics Receptor affinity Dissociation constant, Kd , is the concentration of free ligand required to occupy half the receptors present (similar to Km for enzymes) Receptor down-regulation Receptor-mediated endocytosis Desensitization Agonists vs. antagonists Can be used as drugs to treat medical problems D. Signal transduction cascades Signaling integration Converging vs. diverging signaling cascades Signal amplification II. G-protein Coupled Receptors (GPCRs) A. Structure of GPCRs 7 membrane-spanning segments Intracellular segment interacts with G proteins (guanine-nucleotide binding protein) B. Activation and inactivation of G proteins subunits dissociate and cause a variety of signaling cascades Types of subunits C. Second messengers 1. Cyclic AMP (cAMP) pathway 2. Inositol triphosphate and diacylglycerol pathway BIO 330 Cell Biology Lecture Outline Spring 2011 IP3 leads to increased intracellular Ca2+ DAG leads to PKC activation 3. Nitric oxide D. Transduction of signals via subunits of G proteins III. Protein Kinase-Associated Receptors A. Tyrosine vs. serine/threonine kinases B. Growth factors bind protein-kinase associated receptors C. Receptor tyrosine kinases (RTKs) Structure Activation Signal transuduction cascade Ras and MAP kinase Other pathways Role of scaffolding complexes Dominant negative mutants in research D. Receptor Ser/Thr kinases TGF-b family (transforming growth factor) Smads are used in intracellular signaling DNA binding proteins E. CREB and STATs (Chapter 23; pp. 742-742) Examples of transcription factors activated by intracellular signal transduction IV. Intracellular Receptors (Chapter 23; pp. 739-741) A. Steroid hormone receptors Transcription factors Hormone response elements DNA binding domains V. Hormonal Signaling A. Hormone definition Endocrine product released into the bloodstream to act on a distant target tissue B. Control of glucose metabolism as an example Adrenergic receptors Insulin pathway VI. Cell Signaling and Apoptosis A. Programmed cell death sequence of events DNA segregates, cytoplasm shrinks Membrane blebs, nucleus & organelles fragment Cell is dismantled into apoptotic bodies BIO 330 Cell Biology Lecture Outline Spring 2011 Cellular debris is engulfed by macrophages B. Caspases Master regulators of apoptosis (cysteine and aspartic acid residues are vital to activity) Procaspases are activated by cleavage Caspases then cleave other proteins C. Signaling pathways leading to apoptosis Cell death signals TNF and CD95/Fas Initiator caspases vs. executioner caspases Mitochondria Bcl-2: anti-apoptotic vs. pro-apoptotic proteins Cytochrome c p53