BL 424 Chapter 15: Cell Signaling; Signal Transduction

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "BL 424 Chapter 15: Cell Signaling; Signal Transduction"

Transcription

1 BL 424 Chapter 15: Cell Signaling; Signal Transduction All cells receive and respond to signals from their environments. The behavior of each individual cell in multicellular plants and animals must be carefully regulated to meet the needs of the organism. This is accomplished by a variety of signaling molecules that are secreted or expressed on the surface of one cell and bind to receptors expressed on other cells, thereby integrating and coordinating the functions of cells. The binding of most signaling molecules to their (cell surface) receptors initiates a series of intracellular reactions that regulate all aspects of cell behavior: metabolism, movement, proliferation, differentiation. The study of these processes remains a major area of research, in large part because breakdown of signaling paths results in cancer. Student Learning Outcomes: Transmembrane proteins outside the cell communicate signals to the inside 1*. to explain the various signaling molecules and their cell surface receptors: how cells receive information from outside. 2*. to explain the several general ways signals to receptors are transmitted through the cell to regulate processes (second messenger pathways) 3. to describe examples of signal transduction in development and differentiation, 4. to describe the involvement of the cytoskeleton in signal transduction. Important Figures: 1*, 3*, 4*, 5, 6, 11, 12*, 13*, 14, 15*, 16*, 19, 20, 21*, 22, 25, 26*, 27, 28,* 29, 30, 31, 32, 34*, 35, 41, 42, 43*, 44, 45, 46*; Table: 1* Signaling molecules and their receptors. Signaling can involve direct cell-cell contact (cell-matrix) including integrins and cadherins A common mode of cell-cell signaling involves secreted molecules that bind to receptors on target cells. Signaling is categorized according to distance signals are transmitted: (Fig. 15.1) Endocrine distant - many hormones (e.g., estrogen) Paracrine local many neurotransmitters Autocrine self ex. T lymphocytes respond to antigen by synthesizing growth factors to stimulate proliferation **a. Steroid hormones and nuclear receptor superfamily. Hormones are hydrophobic (Fig. 15.2); diffuse across plasma membrane to bind intracellular receptors. Nuclear receptor family are transcription factors that bind specific DNA targets and activate transcription when hormone is bound to them (Figs. 15.3, 4). Ex. estrogen, progesterone, thyroid hormone, glucocorticoid Retinoic acid, vitamin D receptors GR bound to Hsp90 is inactive; Glucocorticoid makes GR active (binds coactivator HAT, transcription) TR normally repressing complex; T makes it active (binds coactivator HAT)

2 b. Nitric oxide (and carbon monoxide) Paracrine signaling in nervous system, immune, circulatory Ex. dilation of blood vessels (Fig. 15.5) Nitric oxide synthase: arg + O 2 -> citrulline + NO NO diffuses across membranes, affects enzymes Ex. guanylyl cyclase makes cyclic GMP (2 nd messenger) **c. Neurotransmitters are small hydrophilic molecules that carry signals between neurons, or between neurons and other target cells at synapses. (Fig. 15.6) Ex. acetylcholine, dopamine, glutamate Many bind to cell-surface ligand-gated ion channels (Figs , 25) Others bind cell-surface receptors, and are coupled to G proteins to indirectly regulate an ion channel. Some neurotransmitters are also hormones: Ex. epinephrine (adrenaline) signals glycogen breakdown in muscles **d. Peptide hormones and growth factors These molecules have diverse sizes (5-230 aa) and roles: Ex. insulin, endorphin, nerve growth factor (NGF), epidermal growth factor (EGF) (Table 1). Signal does not enter cell, but binds cell-surface Transmembrane receptor Neuropeptides are secreted by some neurons; Some act as hormones on distant cells (enkephalins, endorphins). Growth factors are polypeptides and regulate cell growth: NGF affects nerve cells. EGF (53-aa) stimulates cell proliferation (fig. 15.7). e. Eicosanoids are lipids that function in paracrine or autocrine signaling: ex. prostaglandin, leukotriene (Fig.15. 8) They are synthesized from arachidonic acid (which is derived from phospholipids). Aspirin (NSAID) reduces inflammation & pain by inhibiting synthesis of prostaglandins (reduces platelet aggregation, blood clotting) f. Plant hormones are small molecules that regulate plant growth: (Fig. 15.9) auxin, gibberrellin, ethylene Some activate protein kinases Auxin also stimulates ubiquitination And degradation of a repressor of ARF (auxin response factor)

3 **15.2 Functions of cell-surface receptors Most ligands bind receptors on surface of target cell; Signal is transmitted inside. Some receptors are ligand-gated ion channels that directly control activity (Ch. 13) Other receptors regulate activity of intracellular proteins, Which transmits signal to intracellular target (often transcription factors). a. G-protein coupled receptors are the largest family: (1000); transmembrane proteins (7 times) (Fig. 11) Includes receptors for many hormones, eicosanoids, neurotransmitters, neuropeptides, also smell, taste, sight. Hormone causes receptor to transmit signals to intracellular targets via intermediary action of heterotrimeric G proteins (Fig. 13). Hormone binding to extracellular part of receptor causes shape change in cytoplasmic part, which then binds G protein. The α subunit binds GTP, is activated and dissociates from βγ. α subunit binds to enzyme or ion channel protein to transmit signal. (βγ can also transmit signals) Ex. epinephrine receptor regulates target enzyme of adenylyl cyclase (Fig. 12): ATP -> camp ex. Acetylcholine regulates ion channels via receptor which is ligand-gated ion channel. Acetylcholine and different receptor can regulate Heart muscle via G proteins Mammals have 20 a, 5 β and 12 γ, so different combinations for different receptors and can inhibit or stimulate when activated b. Receptor protein-tyrosine kinases (RTK) Receptors are directly linked to intracellular enzyme activity; includes receptors for most growth factors (Fig. 14). ex. insulin, EGF, NGF receptors Receptors have N-terminal extracellular portion, C-terminal tyr kinase; Binding of hormone causes receptor dimerization and autophosphorylation (Fig *), Other proteins bind the Phospho-peptide of RTK; these proteins localize and get phoshorylated, and then are stimulated and transmit signal. They bind via SH2 domain (Src homology 2, RSV oncogene) or PTB domain (phospho-tyrosine binding) (Fig ).

4 c. Cytokine receptors often act associated non-covalent with cytoplasmic nonreceptor protein-tyrosine kinases. (Fig ) Ex. interleukins, erythropoietin, Some polypeptide hormones (growth hormones) Receptors have N-terminal extracell ligand-binding domain, C-terminal cytosolic (no enzyme activity). Ligand binding stimulates cross-phosphorylation of associated protein tyr kinases: Janus kinase (JAK) family Src kinase family (has SH2 domains) d. Receptors linked to other enzymatic activities: Protein-tyrosine phosphatases removes phosphates often terminates signaling, some are cell surface CD45 on B and T cells dephosphorylates a phospho-tyr residue that was inhibiting a Src kinase and therefore stimulates. Protein-serine/threonine kinases TGF-β receptor for transforming growth factor β Binding of polypeptide growth factor -> receptors dimerize, phosphorylate self and bind, PO4 Smads, which stimulate gene expression Guanylyl cyclases Receptor directly linked to cgmp activity Protease-associated Apoptosis TNF (Ch. 16) Tumor necrosis factor signals proteolysis **15.3 Pathways of intracellular signal transduction. Binding of signal to cell surface receptor stimulates intracellular targets, including enzymes or transcription; directly or indirectly via proteins coupled to receptors. Hormone outside the cell is the first signal; intracellular second messengers are small molecules and enzymes. Enzymes amplify and propagate ligand signal; often consist of cascades of reactions that affect gene expression or cell metabolism. A*. camp pathway and protein phosphorylation Many hormones and odorants use cyclic AMP (camp) as second message in animal cells. Ex. Epinephrine signals glycogen breakdown to glucose in muscle cells. (Fig ) G-protein coupled receptors stimulate adenylyl cyclase to make camp from ATP. Phosphodiesterase degrades camp to AMP to remove signal.

5 Most actions of camp are mediated by protein kinase A (PKA) (Fig. 19, 20); Binding of camp dissociates regulatory subunit. Active PKA adds phosphate to ser/thr of enzymes; PO 4 of phosphorylase kinase makes it active; PO 4 of glycogen synthase makes it inactive. PO 4 Of transcription factor CREB (camp response element binding factor) (Fig. 22) stimulates transcription. Phosphatases (protein phosphatase 1) stop signal; Odorant hormones stimulate via camp to open a Na+ channel. b. cyclic GMP (cgmp) is also a second messenger. cgmp is formed by guanylyl cyclases; is degraded by phosphodiesterase ex. visual reception in vertebrate eye: light activates via G protein transducin (Fig ) which stimulates cgmp phosphodieseterase; decreased cgmp stimulates nerve. C*. Phospholipids and Ca++ are common second messengers. Phosphatidyl inositol 4,5 bisphosphate (PIP2) (Fig ) Is found in inner leaflet of plasma membrane. Hormones and growth factors stimulate hydrolysis Of PIP2 by Phospholipase C (PLC) to form: Diacylglycerol (DAG) in the membrane Iinositol triphosphate (IP3) in cytosol. These compounds activate two signaling paths. DAG activates protein kinase C (PKC) and signals cell growth. IP3 binds IP3 receptor on ER, and mobilizes Ca++ from intracellular stores (ER lumen). Increased Ca++ activates targets, often mediated by Calmodulin binding Ca++, and then binding to Calmodulin-dependent protein kinases which add Phosphates to other enzymes (Fig ) Ex. myosin light chain kinase (Ch. 13). In electrically excitable cells of nerve and muscle, Ca++ is increased by opening of voltage-gated Ca++ channels in plasma membrane, and ryanodine receptors in the ER and sarcoplasmic reticulum (Fig ). Increased Ca++ triggers release of neurotransmitter, muscle contraction.

6 PI3-kinase/AKT and mtor path PIP2 also gets phosphorylated to second messenger PIP3: By enzyme PI3-kinase (Fig ). Binds protein ser/tr kinase AKT (Fig ) which then gets phosphorylated by two protein kinases. Active AKT phosphorylates target proteins for cell survival (Ch. 16). One target is mtor, central regulator of cell growth. D*. Ras, Raf and MAP kinase pathway is conserved chain of protein kinases which convey downstram signals. (Fig *). MAP kinases (Mitogen-activated protein kinases) are ser/thr kinases that respond to growth factors (figs ,39). In animal cells, best-characterized pathway is growth factor receptors and small GTP binding protein Ras, which initates kinase cascade via Raf kinases (ser/thr) to MEK (thr, tyr) to the MAP kinase (ERK, extracell signal regulated kinase) Activated ERK adds PO 4 to cytosolic and nuclear proteins, including transcription factor Elk-1 (fig ). Binding of growth factor to RTK, and its phosphorylation recruited GRB2 and SOS (GEF) to give Ras GTP (Fig ). Ras is normal protein, required for cell function (proto-oncogene). Ras protein was first found as mutated version: oncogene carried by virus (Rat sarcoma virus); mutated Ras binds GTP and is always active. Normally, monomer Ras is activated by GTP binding. Ras and relatives are ½ size of the G protein Gα, Ran (nuclear transport), Rab (vesicle fusion), Rho (cytoskeleton). e. JAK/STAT pathway and TGFβ/Smad. (Fig. 40, 41) STAT proteins are transcription proteins containing SH2 domains. They are activated directly by JAK protein-tyr kinases associated with cytokine and growth factor receptors. STAT (signal transducers & activators of transcription). NFKβ family of transcription factors (Fig. 42). Are important in immune system. Signal outside -> inhibitory IKβ gets PO 4 by IKβ kinase -> NFKβ goes to nucleus to stimulate transcription.

7 f. Hedgehog, Wnt and Notch signaling. These signals, discovered in Drosophila, Are critical for development, patterning organism. Transmembrane receptor, secreted signals (Figs , 44, 45) Hedgehog and Wnt pathways act to prevent degradation of transcription factors that are held in complexes in cytoplasm. Notch is receptor in membrane upon receiving signal from neighboring cell, cytoplasmic fragment is cleaved and goes to nucleus Signal transduction and the cytoskeleton a. Integrins and signal transduction. Binding of integrins to extracellular matrix stimulates nonreceptor protein-tyr kinases FAK (Focal Adhesion kinase) and Src -> Activation of Phospholipase C (PLC), PI3-kinase and Ras/Raf/ERK paths (Figs ) b. Regulation of actin cytoskeleton (Figs ) Occurs through growth factors that induce alterations Mediated by members of Rho subfamily of small GTP-binding proteins (Rho, Rac, Cdc42). Myosin light chain kinase 15.5 Signaling networks Include feedback for NFKβ (Φιγσ ) Cross-talk ERK path & G-coupled receptors & B-arrestin (Fig ) Assemble networks different ways positive or negative (fig ) Questions for review: Questions, all but #9. Diagram a plasma membrane with the two major signaling paths. Consider effects of mutations of the receptors, enzymes Prepare list of major types of signals, of enzymes and what they do.

Cell Signaling (part 1)

Cell Signaling (part 1) 15 Cell Signaling (part 1) Introduction Bacteria and unicellular eukaryotes respond to environmental signals and to signaling molecules secreted by other cells for mating and other communication. In multicellular

More information

G-Protein Signaling. Introduction to intracellular signaling. Dr. SARRAY Sameh, Ph.D

G-Protein Signaling. Introduction to intracellular signaling. Dr. SARRAY Sameh, Ph.D G-Protein Signaling Introduction to intracellular signaling Dr. SARRAY Sameh, Ph.D Cell signaling Cells communicate via extracellular signaling molecules (Hormones, growth factors and neurotransmitters

More information

Chapter 20. Cell - Cell Signaling: Hormones and Receptors. Three general types of extracellular signaling. endocrine signaling. paracrine signaling

Chapter 20. Cell - Cell Signaling: Hormones and Receptors. Three general types of extracellular signaling. endocrine signaling. paracrine signaling Chapter 20 Cell - Cell Signaling: Hormones and Receptors Three general types of extracellular signaling endocrine signaling paracrine signaling autocrine signaling Endocrine Signaling - signaling molecules

More information

Chapter 11. Cell Communication

Chapter 11. Cell Communication Chapter 11 Cell Communication Overview: The Cellular Internet Cell-to-cell communication Is absolutely essential for multicellular organisms Concept 11.1: External signals are converted into responses

More information

Chapter 15: Signal transduction

Chapter 15: Signal transduction Chapter 15: Signal transduction Know the terminology: Enzyme-linked receptor, G-protein linked receptor, nuclear hormone receptor, G-protein, adaptor protein, scaffolding protein, SH2 domain, MAPK, Ras,

More information

Plasma membranes. Plasmodesmata between plant cells. Gap junctions between animal cells Cell junctions. Cell-cell recognition

Plasma membranes. Plasmodesmata between plant cells. Gap junctions between animal cells Cell junctions. Cell-cell recognition Cell Communication Cell Signaling Cell-to-cell communication is essential for multicellular organisms Communicate by chemical messengers Animal and plant cells have cell junctions that directly connect

More information

Cell Communication. Chapter 11. PowerPoint Lectures for Biology, Seventh Edition. Lectures by Chris Romero. Neil Campbell and Jane Reece

Cell Communication. Chapter 11. PowerPoint Lectures for Biology, Seventh Edition. Lectures by Chris Romero. Neil Campbell and Jane Reece Chapter 11 Cell Communication PowerPoint Lectures for Biology, Seventh Edition Neil Campbell and Jane Reece Lectures by Chris Romero Overview: The Cellular Internet Cell-to-cell communication Is absolutely

More information

Cell Communication. Chapter 11. Biology Eighth Edition Neil Campbell and Jane Reece. PowerPoint Lecture Presentations for

Cell Communication. Chapter 11. Biology Eighth Edition Neil Campbell and Jane Reece. PowerPoint Lecture Presentations for Chapter 11 Cell Communication PowerPoint Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp

More information

Propagation of the Signal

Propagation of the Signal OpenStax-CNX module: m44452 1 Propagation of the Signal OpenStax College This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License 3.0 By the end of this section,

More information

2013 W. H. Freeman and Company. 12 Signal Transduction

2013 W. H. Freeman and Company. 12 Signal Transduction 2013 W. H. Freeman and Company 12 Signal Transduction CHAPTER 12 Signal Transduction Key topics: General features of signal transduction Structure and function of G protein coupled receptors Structure

More information

BIOLOGY. Cell Communication CAMPBELL. Reece Urry Cain Wasserman Minorsky Jackson. Lecture Presentation by Nicole Tunbridge and Kathleen Fitzpatrick

BIOLOGY. Cell Communication CAMPBELL. Reece Urry Cain Wasserman Minorsky Jackson. Lecture Presentation by Nicole Tunbridge and Kathleen Fitzpatrick CAMPBELL BIOLOGY TENTH EDITION Reece Urry Cain Wasserman Minorsky Jackson 11 Cell Communication Lecture Presentation by Nicole Tunbridge and Kathleen Fitzpatrick Cellular Messaging Cells can signal to

More information

Physiology Unit 1 CELL SIGNALING: CHEMICAL MESSENGERS AND SIGNAL TRANSDUCTION PATHWAYS

Physiology Unit 1 CELL SIGNALING: CHEMICAL MESSENGERS AND SIGNAL TRANSDUCTION PATHWAYS Physiology Unit 1 CELL SIGNALING: CHEMICAL MESSENGERS AND SIGNAL TRANSDUCTION PATHWAYS In Physiology Today Cell Communication Homeostatic mechanisms maintain a normal balance of the body s internal environment

More information

Principles of cell signaling Lecture 4

Principles of cell signaling Lecture 4 Principles of cell signaling Lecture 4 Johan Lennartsson Molecular Cell Biology (1BG320), 2014 Johan.Lennartsson@licr.uu.se 1 Receptor tyrosine kinase-induced signal transduction Erk MAP kinase pathway

More information

Cell Communication. Chapter 11. Key Concepts in Chapter 11. Cellular Messaging. Cell-to-cell communication is essential for multicellular organisms

Cell Communication. Chapter 11. Key Concepts in Chapter 11. Cellular Messaging. Cell-to-cell communication is essential for multicellular organisms Chapter 11 Cell Communication Dr. Wendy Sera Houston Community College Biology 1406 Key Concepts in Chapter 11 1. External signals are converted to responses within the cell. 2. Reception: A signaling

More information

Cell Communication. Chapter 11. Biology. Eighth Edition Neil Campbell and Jane Reece. PowerPoint Lecture Presentations for

Cell Communication. Chapter 11. Biology. Eighth Edition Neil Campbell and Jane Reece. PowerPoint Lecture Presentations for Chapter 11 Cell Communication PowerPoint Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp

More information

Signal Transduction Cascades

Signal Transduction Cascades Signal Transduction Cascades Contents of this page: Kinases & phosphatases Protein Kinase A (camp-dependent protein kinase) G-protein signal cascade Structure of G-proteins Small GTP-binding proteins,

More information

Cell responses to environment-- Signals

Cell responses to environment-- Signals Cell responses to environment-- Signals Signal transduction can coordinate: Development Formation of tissues Timing of cell division Direction of cell enlargement Size and shape of organs Responses to

More information

Cell Communication. Chapter 11. Biology. Eighth Edition Neil Campbell and Jane Reece. PowerPoint Lecture Presentations for

Cell Communication. Chapter 11. Biology. Eighth Edition Neil Campbell and Jane Reece. PowerPoint Lecture Presentations for Chapter 11 Cell Communication PowerPoint Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp

More information

Cell Communication. Cell Communication. Communication between cells requires: ligand: the signaling molecule

Cell Communication. Cell Communication. Communication between cells requires: ligand: the signaling molecule Cell Communication Cell Communication Communication between cells requires: ligand: the signaling molecule receptor protein: the molecule to which the ligand binds (may be on the plasma membrane or within

More information

Cell Cell Communication

Cell Cell Communication IBS 8102 Cell, Molecular, and Developmental Biology Cell Cell Communication January 29, 2008 Communicate What? Why do cells communicate? To govern or modify each other for the benefit of the organism differentiate

More information

Cellular Signaling Pathways. Signaling Overview

Cellular Signaling Pathways. Signaling Overview Cellular Signaling Pathways Signaling Overview Signaling steps Synthesis and release of signaling molecules (ligands) by the signaling cell. Transport of the signal to the target cell Detection of the

More information

Bio 111 Study Guide Chapter 11 Cell Communication

Bio 111 Study Guide Chapter 11 Cell Communication Bio 111 Study Guide Chapter 11 Cell Communication BEFORE CLASS: Reading: Read the introduction on p. 210, and for Concept 11.1, read from the first full paragraph on p. 212. Read all of Concept 11.2. Pay

More information

Cellular Communication

Cellular Communication Cellular Communication But before we get into that What have we learned about so far? Energy and Matter Why do living things need energy? Grow Reproduce Maintain homeostasis Cellular signaling Cells communicate

More information

BIOLOGY. Cell Communication. Outline. Evolution of Signaling. Overview: Cellular Messaging. Local and Long-Distance Signaling

BIOLOGY. Cell Communication. Outline. Evolution of Signaling. Overview: Cellular Messaging. Local and Long-Distance Signaling 11 CAMBELL BIOLOGY TENTH EDITION Reece Urry Cain Wasserman Minorsky Jackson Cell Communication Lecture resentation by Dr Burns NVC Biol 120 Outline I. Cell Signaling II. Forms of cell signaling III. Quick

More information

MCB*4010 Midterm Exam / Winter 2008

MCB*4010 Midterm Exam / Winter 2008 MCB*4010 Midterm Exam / Winter 2008 Name: ID: Instructions: Answer all 4 questions. The number of marks for each question indicates how many points you need to provide. Write your answers in point form,

More information

Cell Biology Lecture 9 Notes Basic Principles of cell signaling and GPCR system

Cell Biology Lecture 9 Notes Basic Principles of cell signaling and GPCR system Cell Biology Lecture 9 Notes Basic Principles of cell signaling and GPCR system Basic Elements of cell signaling: Signal or signaling molecule (ligand, first messenger) o Small molecules (epinephrine,

More information

Organization of lectures: Cell Signaling I: Sex, Drugs and Violence. Cell signaling is central to modern medicine. Forms of Cell Signaling

Organization of lectures: Cell Signaling I: Sex, Drugs and Violence. Cell signaling is central to modern medicine. Forms of Cell Signaling Cell Signaling I: Sex, Drugs and Violence Joe W. Ramos jramos@crch.hawaii.edu www.crch.org/profiles/jramos Organization of lectures: General Principles of signaling cascades Hormone Signaling Signaling

More information

GPCR. General Principles of Cell Signaling G-protein-Coupled Receptors Enzyme-Coupled Receptors Other Signaling Pathways. G-protein-Coupled Receptors

GPCR. General Principles of Cell Signaling G-protein-Coupled Receptors Enzyme-Coupled Receptors Other Signaling Pathways. G-protein-Coupled Receptors G-protein-Coupled Receptors General Principles of Cell Signaling G-protein-Coupled Receptors Enzyme-Coupled Receptors Other Signaling Pathways GPCR G-protein-coupled receptors Figure 15-30 Molecular Biology

More information

Cell Communication. Chapter 11. Overview: The Cellular Internet

Cell Communication. Chapter 11. Overview: The Cellular Internet Chapter 11 Cell Communication Overview: The Cellular Internet Cell-to-cell communication is essential for multicellular organisms Biologists have discovered some universal mechanisms of cellular regulation

More information

The plasma membrane plays a key role in most cell signaling

The plasma membrane plays a key role in most cell signaling CONCEPT 5.6 The plasma membrane plays a key role in most cell signaling In a multicellular organism, whether a human being or an oak tree, it is cell-to-cell communication that allows the trillions of

More information

Computational Biology I LSM5191

Computational Biology I LSM5191 Computational Biology I LSM5191 Aylwin Ng, D.Phil Lecture 6 Notes: Control Systems in Gene Expression Pulling it all together: coordinated control of transcriptional regulatory molecules Simple Control:

More information

Resp & Cell Comm Review

Resp & Cell Comm Review Resp & Cell Comm Review Two main catabolic processes: fermentation: partial degradation of sugars in the absence of oxygen. cellular respiration: uses oxygen to complete the breakdown of many organic molecules.

More information

Biochemie 4. Cell communication - GPCR

Biochemie 4. Cell communication - GPCR Biochemie 4 Cell communication - GPCR 1 Lecture outline General principles - local and long-distance signaling - classes of receptors - molecular switches and second messengers Receptor tyrosine kinases

More information

Hormones and Signal Transduction. Dr. Kevin Ahern

Hormones and Signal Transduction. Dr. Kevin Ahern Dr. Kevin Ahern Signaling Outline Signaling Outline Background Signaling Outline Background Membranes Signaling Outline Background Membranes Hormones & Receptors Signaling Outline Background Membranes

More information

Cell Biology (BIOL 4374 and BCHS 4313) Third Exam 4/24/01

Cell Biology (BIOL 4374 and BCHS 4313) Third Exam 4/24/01 Cell Biology (BIOL 4374 and BCHS 4313) Third Exam 4/24/01 Name SS# This exam is worth a total of 100 points. The number of points each question is worth is shown in parentheses. For multiple choice questions,

More information

Close to site of release (at synapse); binds to receptors in

Close to site of release (at synapse); binds to receptors in Chapter 18: The Endocrine System Chemical Messengers 1. Neural 2. Endocrine 3. Neuroendocrine 4. Paracrine 5. Autocrine Endocrine System --Endocrine and nervous systems work together --Endocrine vs. Nervous

More information

KEY CONCEPT QUESTIONS IN SIGNAL TRANSDUCTION

KEY CONCEPT QUESTIONS IN SIGNAL TRANSDUCTION Signal Transduction - Part 2 Key Concepts - Receptor tyrosine kinases control cell metabolism and proliferation Growth factor signaling through Ras Mutated cell signaling genes in cancer cells are called

More information

Cellular Messengers. Intracellular Communication

Cellular Messengers. Intracellular Communication Cellular Messengers Intracellular Communication Most common cellular communication is done through extracellular chemical messengers: Ligands Specific in function 1. Paracrines Local messengers (neighboring

More information

G-Protein-Coupled Receptors

G-Protein-Coupled Receptors Cellular Signalling Cells must be ready to respond to essential signals in their environment. These are often chemicals in the extracellular fluid (ECF) from distant locations in a multicellular organism

More information

Cell Communication - 1

Cell Communication - 1 Cell Communication - 1 Just as we communicate with other humans (a number of different ways), cells communicate with other cells, to interact with the external environment and to make appropriate responses

More information

HORMONES (Biomedical Importance)

HORMONES (Biomedical Importance) hormones HORMONES (Biomedical Importance) Hormones are the chemical messengers of the body. They are defined as organic substances secreted into blood stream to control the metabolic and biological activities.

More information

Chapter 11: Cell Communication

Chapter 11: Cell Communication Name Period Chapter 11: Cell Communication The special challenge in Chapter 11 is not that the material is so difficult, but that most of the material will be completely new to you. Cell communication

More information

11/8/16. Cell Signaling Mechanisms. Dr. Abercrombie 11/8/2016. Principal Parts of Neurons A Signal Processing Computer

11/8/16. Cell Signaling Mechanisms. Dr. Abercrombie 11/8/2016. Principal Parts of Neurons A Signal Processing Computer Cell Signaling Mechanisms Dr. Abercrombie 11/8/2016 Principal Parts of Neurons A Signal Processing Computer A Multitude of Synapses and Synaptic Actions Summation/Synaptic Integration 1 The Synapse Signal

More information

Cellular Communication

Cellular Communication (a) Communicating cell junctions. by direct cell-cell contact lasma membranes 1. Direct cell contact. Vesicle-mediated 3. Chemical messengers (b) Cell-cell recognition. Gap junctions between animal cells

More information

Molecular Bioscience 401: Lecture 11.1 Cell Signaling. Slide #1

Molecular Bioscience 401: Lecture 11.1 Cell Signaling. Slide #1 Molecular Bioscience 401: Lecture 11.1 Cell Signaling Slide #1 Cell Communication Necessary for multicellular organisms Unlike unicellular organisms, multicellular Organisms require elaborate cell communication

More information

INTERACTION DRUG BODY

INTERACTION DRUG BODY INTERACTION DRUG BODY What the drug does to the body What the body does to the drug Receptors - intracellular receptors - membrane receptors - Channel receptors - G protein-coupled receptors - Tyrosine-kinase

More information

Lecture 36: Review of membrane function

Lecture 36: Review of membrane function Chem*3560 Lecture 36: Review of membrane function Membrane: Lipid bilayer with embedded or associated proteins. Bilayers: 40-70% neutral phospholipid 10-20% negative phospholipid 10-30% cholesterol 10-30%

More information

Hormones. Prof. Dr. Volker Haucke Institut für Chemie-Biochemie Takustrasse 6

Hormones. Prof. Dr. Volker Haucke Institut für Chemie-Biochemie Takustrasse 6 Hormones Prof. Dr. Volker Haucke Institut für Chemie-Biochemie Takustrasse 6 Tel. 030-8385-6920 (Sekret.) 030-8385-6922 (direkt) e-mail: vhaucke@chemie.fu-berlin.de http://userpage.chemie.fu-berlin.de/biochemie/aghaucke/teaching.html

More information

target effector enzyme is Phospholipase C A. target protein adenylate cyclase camp-> PKA B. target protein phospholipase C two 2nd Messengers:

target effector enzyme is Phospholipase C A. target protein adenylate cyclase camp-> PKA B. target protein phospholipase C two 2nd Messengers: COR 011 Cell Communication II Lect 19 Lecture Outline Signal molecule Activated Ras-GT A G-rotein And they tell friends And they tell friends And they tell friends 1. Finish Trimeric G-rotein: hospholipase

More information

Enzymes Part III: regulation II. Dr. Mamoun Ahram Summer, 2017

Enzymes Part III: regulation II. Dr. Mamoun Ahram Summer, 2017 Enzymes Part III: regulation II Dr. Mamoun Ahram Summer, 2017 Advantage This is a major mechanism for rapid and transient regulation of enzyme activity. A most common mechanism is enzyme phosphorylation

More information

Communication with environment

Communication with environment presents Communication with environment A Montagud E Navarro P Fernández de Córdoba JF Urchueguía signal transduction signal lipophilic hormones gas hydrophilic hormones neurotransmitters receptor cytosol

More information

Signaling Molecules and Cellular Receptors

Signaling Molecules and Cellular Receptors Signaling Molecules and Cellular Receptors Bởi: OpenStaxCollege There are two kinds of communication in the world of living cells. Communication between cells is called intercellular signaling, and communication

More information

Chapter 11 Cell Communication

Chapter 11 Cell Communication Chapter 11 Cell Communication Lecture Outline Overview: Cellular Messaging Cell-to-cell communication allows the trillions of cells in a multicellular organism to communicate to coordinate their activities.

More information

What is the function (purpose) of this system? (clue: one word)

What is the function (purpose) of this system? (clue: one word) Endocrine System: Overview What is the function (purpose) of this system? (clue: one word) Communication! The role of hormones is to provide communication between cells (tissues and organs). There are

More information

LQB383 Testbank. Week 8 Cell Communication and Signaling Mechanisms

LQB383 Testbank. Week 8 Cell Communication and Signaling Mechanisms LQB383 Testbank Week 8 Cell Communication and Signaling Mechanisms Terms to learn match the terms to the definitions --------------------------------------------------------------------------------------------------------------------------

More information

Lojayn Salah. Razan Aburumman. Faisal Muhammad

Lojayn Salah. Razan Aburumman. Faisal Muhammad 20 Lojayn Salah Razan Aburumman Faisal Muhammad Note: I tried to include everything that's important from the doctor's slides but you can refer back to them after studying this sheet.. After you read this

More information

The Endocrine System. PowerPoint Lecture Presentations prepared by Jason LaPres. Lone Star College North Harris

The Endocrine System. PowerPoint Lecture Presentations prepared by Jason LaPres. Lone Star College North Harris 18 The Endocrine System PowerPoint Lecture Presentations prepared by Jason LaPres Lone Star College North Harris NOTE: Presentations extensively modified for use in MCB 244 & 246 at the University of Illinois

More information

BL 424 Test pts name Multiple choice have one choice each and are worth 3 points.

BL 424 Test pts name Multiple choice have one choice each and are worth 3 points. BL 424 Test 3 2010 150 pts name Multiple choice have one choice each and are worth 3 points. 1. The plasma membrane functions as a a. selective barrier to the passage of molecules. b. sensor through which

More information

Review II: Cell Biology

Review II: Cell Biology Review II: Cell Biology Rajan Munshi BBSI @ Pitt 2006 Department of Computational Biology University of Pittsburgh School of Medicine May 24, 2006 Outline Cell Cycle Signal Transduction 1 Cell Cycle Four

More information

Biol403 MAP kinase signalling

Biol403 MAP kinase signalling Biol403 MAP kinase signalling The mitogen activated protein kinase (MAPK) pathway is a signalling cascade activated by a diverse range of effectors. The cascade regulates many cellular activities including

More information

Pharmacodynamics. OUTLINE Definition. Mechanisms of drug action. Receptors. Agonists. Types. Types Locations Effects. Definition

Pharmacodynamics. OUTLINE Definition. Mechanisms of drug action. Receptors. Agonists. Types. Types Locations Effects. Definition Pharmacodynamics OUTLINE Definition. Mechanisms of drug action. Receptors Types Locations Effects Agonists Definition Types Outlines of Pharmacodynamics Antagonists Definition Types Therapeutic Index Definition

More information

Copyright Mark Brandt, Ph.D. 128

Copyright Mark Brandt, Ph.D. 128 Signal transduction In order to interact properly with their environment, cells need to allow information as well as molecules to cross their cell membranes. Information in many single-celled and all multicellular

More information

AP Biology Cells: Chapters 4 & 5

AP Biology Cells: Chapters 4 & 5 AP Biology Cells: Chapters 4 & 5 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The was the first unifying principle of biology. a. spontaneous generation

More information

Cell Signaling and Signal Transduction: Communication between Cells

Cell Signaling and Signal Transduction: Communication between Cells Cell Signaling and Signal Transduction: Communication between Cells - Cell signaling makes it possible for cells to respond in an appropriate manner to a specific environmental stimulus THE BASIC ELEMENTS

More information

Lecture 7: Signaling Through Lymphocyte Receptors

Lecture 7: Signaling Through Lymphocyte Receptors Lecture 7: Signaling Through Lymphocyte Receptors Questions to Consider After recognition of its cognate MHC:peptide, how does the T cell receptor activate immune response genes? What are the structural

More information

Protein kinases are enzymes that add a phosphate group to proteins according to the. ATP + protein OH > Protein OPO 3 + ADP

Protein kinases are enzymes that add a phosphate group to proteins according to the. ATP + protein OH > Protein OPO 3 + ADP Protein kinase Protein kinases are enzymes that add a phosphate group to proteins according to the following equation: 2 ATP + protein OH > Protein OPO 3 + ADP ATP represents adenosine trisphosphate, ADP

More information

Chapter 10. Introduction to Nutrition and Metabolism, 3 rd edition David A Bender Taylor & Francis Ltd, London 2002

Chapter 10. Introduction to Nutrition and Metabolism, 3 rd edition David A Bender Taylor & Francis Ltd, London 2002 Chapter 10 Introduction to Nutrition and Metabolism, 3 rd edition David A Bender Taylor & Francis Ltd, London 2002 Chapter 10: Integration and Control of Metabolism Press the space bar or click the mouse

More information

Biol220 Cell Signalling Cyclic AMP the classical secondary messenger

Biol220 Cell Signalling Cyclic AMP the classical secondary messenger Biol220 Cell Signalling Cyclic AMP the classical secondary messenger The classical secondary messenger model of intracellular signalling A cell surface receptor binds the signal molecule (the primary

More information

MBG301. Class IV. Classification of GPCRs according to their effector function (according to Lodish)

MBG301. Class IV. Classification of GPCRs according to their effector function (according to Lodish) MBG301 Class IV Classification of GPCRs according to their effector function (according to Lodish) 1. Adenylcyclase activation by GPCRs 2. Ion channel regulation by GPCRs 3. Phospholipase C (PLC) activation

More information

RAS Genes. The ras superfamily of genes encodes small GTP binding proteins that are responsible for the regulation of many cellular processes.

RAS Genes. The ras superfamily of genes encodes small GTP binding proteins that are responsible for the regulation of many cellular processes. ۱ RAS Genes The ras superfamily of genes encodes small GTP binding proteins that are responsible for the regulation of many cellular processes. Oncogenic ras genes in human cells include H ras, N ras,

More information

Endocrine Notes Mrs. Laux AP Biology I. Endocrine System consists of endocrine glands (ductless), cells, tissues secrete hormones

Endocrine Notes Mrs. Laux AP Biology I. Endocrine System consists of endocrine glands (ductless), cells, tissues secrete hormones I. Endocrine System consists of endocrine glands (ductless), cells, tissues secrete hormones regulates metabolism, fluid balance, growth, reproduction A. Hormones 1. chemical signals-cell to cell communication

More information

Zool 3200: Cell Biology Exam 4 Part I 2/3/15

Zool 3200: Cell Biology Exam 4 Part I 2/3/15 Name: Trask Zool 3200: Cell Biology Exam 4 Part I 2/3/15 Answer each of the following questions in the space provided, explaining your answers when asked to do so; circle the correct answer or answers

More information

Chapter 9 Signal Transduction and Cell Growth

Chapter 9 Signal Transduction and Cell Growth Part II Principles of Individual Cell Function Chapter 9 One characteristic of organisms is that they exhibit various behaviors in response to changes in their environment (i.e., the outside world). Cells

More information

Hormones, Receptors and Receptor-Hormone Interactions

Hormones, Receptors and Receptor-Hormone Interactions Classification of Hormones Hormones, Receptors and Receptor-Hormone Interactions Synthesis of Protein Hormones and Amine Hormones Hormone Activity Locations of Receptors Mechanisms of Hormone Action Types

More information

Regulation of glycogen degradation

Regulation of glycogen degradation Paper : 04 Metabolism of carbohydrates Module : 26 Principal Investigator Paper Coordinator Content Reviewer Content Writer Dr.S.K.Khare,Professor IIT Delhi. Dr. Ramesh Kothari,Professor UGC-CAS Department

More information

Cell Membranes Valencia college

Cell Membranes Valencia college 6 Cell Membranes Valencia college 6 Cell Membranes Chapter objectives: The Structure of a Biological Membrane The Plasma Membrane Involved in Cell Adhesion and Recognition Passive Processes of Membrane

More information

Endocrinology - Reproduction Introduction Mohammed Y. Kalimi, Ph.D.

Endocrinology - Reproduction Introduction Mohammed Y. Kalimi, Ph.D. Endocrinology - Reproduction Introduction Mohammed Y. Kalimi, Ph.D. Objectives: After studying this material, the student will: 1. Identify the chemical nature of thyroid hormones, TRH, TSH, GH, somatoatatin,

More information

Chapter 15 Signal Transduction and G Protein Coupled Receptors

Chapter 15 Signal Transduction and G Protein Coupled Receptors Chapter 15 Signal Transduction and G Protein Coupled Receptors Signal transduction? Signal transduction (also known as cell signaling) is the transmission of molecular signals from a cell's exterior to

More information

Neuron types and Neurotransmitters

Neuron types and Neurotransmitters Neuron types and Neurotransmitters Faisal I. Mohammed. PhD, MD University of Jordan 1 Transmission of Receptor Information to the Brain the larger the nerve fiber diameter the faster the rate of transmission

More information

Signal Transduction Pathways in Human Diseases

Signal Transduction Pathways in Human Diseases Molecular Cell Biology Lecture. Oct 29, 2015 Signal Transduction Pathways in Human Diseases Ron Bose, MD PhD Biochemistry and Molecular Cell Biology Programs Washington University School of Medicine Introduction

More information

Lecture 17. Regulation of gene expression by second messengers other than camp. camp cgmp IP3 DAG Ca 2+

Lecture 17. Regulation of gene expression by second messengers other than camp. camp cgmp IP3 DAG Ca 2+ Lecture 17 Regulation of gene expression by second messengers other than cam cam cgm I3 DAG Ca 2+ Lectures 15 and 16 Introduction to signal transduction Lipophilic signalling molecules and intracellular

More information

Chapter 15: Signal transduction

Chapter 15: Signal transduction Chapter 15: Signal transduction Know the terminology: Enzyme-linked receptor IP3+DAG G-protein linked receptor camp nuclear hormone receptor Ca 2+ G-protein adaptor protein protein kinase scaffolding protein

More information

Reading Packet 2- Cells Unit. Chapter 6: A Tour of the Cell 1. What is resolving power?

Reading Packet 2- Cells Unit. Chapter 6: A Tour of the Cell 1. What is resolving power? AP Biology Reading Packet 2- Cells Unit Name Chapter 6: A Tour of the Cell 1. What is resolving power? 2. How is an electron microscope different from a light microscope and what is the difference between

More information

Properties of Allosteric Enzymes

Properties of Allosteric Enzymes Properties of Allosteric Enzymes (1) An allosteric enzyme possesses at least spatially distinct binding sites on the protein molecules the active or the catalytic site and the regulator or the allosteric

More information

2/3/15. II - Secreted extracellular messenger one cell talking to another ex. insulin glucagon, growth factors

2/3/15. II - Secreted extracellular messenger one cell talking to another ex. insulin glucagon, growth factors Signal Transduction What is signal transduction? So why do cells need to communicate? -Coordination of movement bacterial movement towards a chemical gradient green algae - colonies swimming through the

More information

Src-INACTIVE / Src-INACTIVE

Src-INACTIVE / Src-INACTIVE Biology 169 -- Exam 1 February 2003 Answer each question, noting carefully the instructions for each. Repeat- Read the instructions for each question before answering!!! Be as specific as possible in each

More information

Name: Class: Date: Unit 1 Test: Cells. Multiple Choice Identify the choice that best completes the statement or answers the question.

Name: Class: Date: Unit 1 Test: Cells. Multiple Choice Identify the choice that best completes the statement or answers the question. Class: _ Date: _ Unit 1 Test: Cells Multiple Choice Identify the choice that best completes the statement or answers the question. 1) Which of the following is true of integral membrane proteins? A) They

More information

Signal-Transduction Pathways

Signal-Transduction Pathways CHATER 12 Signal-Transduction athways 12.1 Signal Transduction Depends on Molecular Circuits 12.2 Receptor roteins Transmit Information Into the Cell 12.3 Metabolism in Context: Insulin Signaling Regulates

More information

Basics of Signal Transduction. Ebaa M Alzayadneh, PhD

Basics of Signal Transduction. Ebaa M Alzayadneh, PhD Basics of Signal Transduction Ebaa M Alzayadneh, PhD What is signal transduction? Cell signaling The science of understanding how individual cells sense their environments and respond to stimuli... how

More information

Endocrine system. Coordination & regulation Glands Hormones

Endocrine system. Coordination & regulation Glands Hormones Endocrine system Coordination & regulation Glands Hormones Endocrine system structures Anatomy - Dispersed system of glands that communicate with each other & all body cells via hormones. Endocrine glands:

More information

Chapter 6: Cancer Pathways. Other Pathways. Cancer Pathways

Chapter 6: Cancer Pathways. Other Pathways. Cancer Pathways Chapter 6: Cancer Pathways Limited number of pathways control proliferation and differentiation Transmit signals from growth factors, hormones, cell-to-cell communications/interactions Pathways turn into

More information

Chapter 20 Endocrine System

Chapter 20 Endocrine System Chapter 20 Endocrine System The endocrine system consists of glands and tissues that secrete Hormones are chemicals that affect other glands or tissues, many times far away from the site of hormone production

More information

Information Transmission and Signal Transduction. Nucleic Acids. Enzymes. Context-Dependent Molecules. Definitions. Endocrine. Paracrine.

Information Transmission and Signal Transduction. Nucleic Acids. Enzymes. Context-Dependent Molecules. Definitions. Endocrine. Paracrine. Information Transmission and Signal Transduction ucleic Acids Enzymes ontext-dependent Molecules Definitions Endocrine aracrine Autocrine ormone Receptor Affinity Specificity apacity Mechanism Type of

More information

Lecture 14. Insect nerve system (II)

Lecture 14. Insect nerve system (II) Lecture 14. Insect nerve system (II) Structures (Anatomy) Cells Anatomy How NS functions Signal transduction Signal transmission Overview More on neurons: ions, ion channel, ligand receptor Signal transduction:

More information

Receptors Functions and Signal Transduction L1- L2

Receptors Functions and Signal Transduction L1- L2 Receptors Functions and Signal Transduction L1- L2 Faisal I. Mohammed, MD, PhD University of Jordan 1 Introduction to Physiology (0501110) Spring 2013 Subject Receptors: types and adaptation - Membrane

More information

Homeostatic Control Systems

Homeostatic Control Systems Homeostatic Control Systems In order to maintain homeostasis, control system must be able to Detect deviations from normal in the internal environment that need to be held within narrow limits Integrate

More information

Hormones and the Endocrine System Chapter 45. Intercellular communication. Paracrine and Autocrine Signaling. Signaling by local regulators 11/26/2017

Hormones and the Endocrine System Chapter 45. Intercellular communication. Paracrine and Autocrine Signaling. Signaling by local regulators 11/26/2017 Hormones and the Endocrine System Chapter 45 Intercellular communication Endocrine signaling Local regulators Paracrine and autocrine signaling Neuron signaling Synaptic and neuroendocrine signaling Paracrine

More information