Posttranslational Modification and Targeting of Proteins
|
|
- Stuart Dalton
- 5 years ago
- Views:
Transcription
1 Posttranslational Modification and Targeting of Proteins Graduate Biochemistry Term 2/2016 Assist. Prof. Dr. Panida Khunkaewla School of Chemistry, Institute of Science Suranaree University of Technology 1
2 What is posttranslational Modification? Modification of nascent protein by adding groups or cleavage of some parts to get mature protein Key wards: Adding Deleting 2
3 Diversity of Posttranslational modification of proteins Cleavage of signal peptides Phosphorylation Amidation Glycosylation Hydroxylation Ubiquitination Addition of prosthetic groups Iodination Prenylation Myristoylation Acylation Acetylation Methylation Oxidative crosslinking N-Glutamyl cyclization Carboxylation Adenylation Sulfonation 3
4 Location Nucleus Lysosome Mitochondria Golgi ER Cytosol Ribosome Plasma membrane Extracelullar fluid Extracellular matrix Modification acetylation, phosphorylation mannose-6-phosphate labelled N-linked sugar N-formyl acylation N- and O-linked ologosaccharide, sulfation, palmitoylation N-linked oligosaccharide, GPI-anchor acetylation, methylation, phosphorylation, myristoylation N- and O-glycosylation, GPI-anchor N- and O-glycosylation, acetylation, phosphorylation N- and O-glycosylation, phosphorylation, hydroxylation 4
5 Proteolytic cleavage Covalent cleavage of one or more peptide bonds in protein substrates by protease. Schematic processing of preproinsulin to proinsulin by signal peptidase in the ER and of proinsulin to insulin by proprotein convertases in the trans Golgi network. Christopher T. W. Posttranslational Modification of Proteins, 2006, Robert and Company Publisher. 5
6 Covalent modifications Covalent addition of a substrate fragment to protein side chain catalyzed by a posttranslational modification enzyme. Examples shown are generic phosphorylation, acetylation, and O-glycosylation. 6 Christopher T. W. Posttranslational Modification of Proteins, 2006, Robert and Company Publisher.
7 Irreversible Modification Irreversible changes include the proteolysis of peptide bonds, installation of phopsphopantertheinyl groups in fatty acids synthase, and N-methylation of lysine residues in histones. 7 Christopher T. W. Posttranslational Modification of Proteins, 2006, Robert and Company Publisher.
8 Reversible Modifications Reversible covalnt modifications including protein phosphorylations (due to balance of kinase and phosphatase), histone acetylation (due to the balance of histone acetyltransferase and histone deacetylase), and protein 8 ubiquitylations (due to the balance of ligases and deubiquitylating hydrolase Christopher T. W. Posttranslational Modification of Proteins, 2006, Robert and Company Publisher.
9 Purpose of posttranslational modification. Targeting of protein Stability of protein Function of protein Control protein activity 9
10 Targeting of proteins How are synthesized proteins directed to their final cellular destination? Secreted protein, membrane protein, inclusion protein in lysosomes Protein destines to mitochondria Protein destines to chloroplast Protein destines to nucleus Cytoplasmic proteins 10
11 Proteins can move between compartments in different ways Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell. 4th edition. New York: Garland Science; Cycles of membrane budding and fusion permit the lumen of any of these organelles to communicate with any other and with the cell exterior by means of transport vesicles. Blue arrows indicate the extensive network of outbound and inbound traffic route. Some organelles, most notably mitochondria and (in plant cells) plastids do not take part in this communication and are isolated from the traffic between organelles shown here. 11
12 Three major ways of protein moving between different compartments 1. In gated transport, the protein traffic between the cytosol and nucleus occurs through the nuclear pore complexes. The nuclear pore complexes function as selective gates that actively transport specific macromolecules and macromolecular assemblies, although they also allow free diffuse of smaller molecules. 2. Intransmembrane transport, membrane-bound protein translocators directly transport specific proteins across a membrane from the cytosol into a space that is topologically distinct. The transported protein molecules usually must unfold to snake through the translocator. The initial transport of selected proteins from the cytosol into the ER lumen or from the cytosol into mitochondria, for example, occurs in this way. 3. In vesicular transport, membrane-enclosed transport intermediates which may be small, spherical transport vesicles or larger, irregularly shaped organelle fragments-ferry protein from one compartment to another. Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell. 4th edition. New York: Garland Science;
13 Signal sequence Signal sequence is a short sequence of amino acids that directed a protein to it appropriate location in the cell and, for many protein, is removed during transport or after the protein has reached to its final destination
14 The Nobel Prize in Physiology or Medicine 1999 "for the discovery that proteins have intrinsic signals that govern their transport and localization in the cell PROTEIN ZIP CODES Albert B. et. al. Molecular Biology of the Cell, 4 th ed,
15 Signal sequence directed to ER The carboxyl terminus of the signal sequence is defined by a cleavage site, where protease action removes the sequence after the protein is imported into the ER. Signal sequences vary in length from 13 to 36 amino acid residues. All signal sequences have the following features: 1) about 10 to 15 hydrophobic amino acid residues 2) one or more positively charged residues, usually near the amino terminus, preceding the hydrophobic sequence 3) a short sequence at the carboxyl terminus (near the cleavage site) that is relatively polar, typically having amino acid residues with short side chains (especially Ala) at the positions closest to the cleavage site. 15
16 Examples of Signal sequences for protein translocation into ER Nelson & Cox, Lehninger Principles of Biochemistry, 4th ed.,
17 Targeting of nuclear proteins 17 Nelson & Cox, Lehninger Principles of Biochemistry, 4th ed., 2005
18 Targeting of mitochondrial proteins Albert B. et. al. Molecular Biology of the Cell, 4 th ed,
19 Three protein translocators in the mitochondria membrane 19 Albert B. et. al. Molecular Biology of the Cell, 4 th ed, 2000
20 Protein import by mitochondria Albert B. et. al. Molecular Biology of the Cell, 4 th ed, 2000 The N-terminal signal sequence of the precursor protein is recognized by receptors of the TOM complex. The protein is thought to be translocated across both mitochondrial membranes at or near special contact sites. The signal sequence is cleaved off by a signal peptidase in the matrix to form the mature protein. The free signal sequence is then rapidly degraded (not shown) 20
21 The role of energy in protein import into the mitochondrial matrix Albert B. et. al. Molecular Biology of the Cell, 4 th ed, Albert B. et. al. Molecular Biology of the Cell, 4 th ed, 2000
22 Translocation of precursor proteins into chloroplast Albert B. et. al. Molecular Biology of the Cell, 4 th ed, 2000 A) The chloroplast signal sequence initiates translocation into the stroma through a membrane contact site by a mechanism similar to that used for translocation into the mitochondrial matrix. The signal sequence is then cleaved off, which initiates translocation across the thylakoid membrane. B) Translocation into the thylakoid space or thylakoid membrane can occur by any one of at least four routes: (1) Sec pathway, uses components that are homologs of Sec proteins, which mediate protein translocation across the bacterial plasma membrane. (2) SRP-like pathway, uses a chloroplast homolog of the signal recognition particle, or SRP (3) ΔpH pathway, it is driven by the H + gradient across the thylakoid membrane, and (4) spontaneous insertion pathway that seems to require no protein trarnslocator for membrane integration. 22
23 The signal hypothesis of protein targeting to ER Nelson & Cox, Lehninger Principles of Biochemistry, 4th ed.,
24 How does a single-pass transmembrane protein become inserted into the ER Albert B. et. al. Molecular Biology of the Cell, 4 th ed, 2000 In addition to the start-transfer sequence as soluble proteins, however, the protein also contains a stoptransfer sequence (orange). When the stop-transfer sequence enters the translocator and interacts with a binding site, the translocator changes its conformation and discharges the protein laterally into the lipid bilayer. 24
25 Integrating of a single-pass membrane protein with an internal signal sequence into the ER (A) (B) Albert B. et. al. Molecular Biology of the Cell, 4 th ed, 2000 If there are more positively charged amino acids immediately preceding the hydrophobic core of the start-transfer sequence than there are following it, the start-transfer sequence is inserted into the translocator in the orientation. The part of the C-terminal to the start-transfer sequence will therefore be passed across the membrane. If there are more positively charged amino acids immediately following the hydrophobic core of the start-transfer sequence than there are preceding it, the start-transfer sequence is inserted into the translocator in the orientation shown here. The part of the N-terminal to the start-transfer sequence will therefore be passed across the membrane. Because translocation cannot start before a start-transfer sequence appears outside the ribosome, translocation of the N-terminal portion of the protein shown in (B) can occur only after this portion has been fully synthesized. 25
26 Integrating of a double-pass membrane protein with an internal signal sequence into the ER Albert B. et. al. Molecular Biology of the Cell, 4 th ed, 2000 An internal ER signal sequence acts as a start-transfer signal and initiates the transfer of the C-terminal part of the protein. At some point after a stop-transfer sequence has entered the translocator, the translocator discharges the sequence laterally into the membrane. 26
27 The attachment of a GPI anchor to a protein in the ER Albert B. et. al. Molecular Biology of the Cell, 4 th ed, ) Immediately after the completion of protein synthesis, the precursor protein remains anchored in the ER membrane by a hydrophobic C-terminal sequence of amino acids; the rest of the protein is in the ER lumen. 2) Within less than a minute, an enzyme in the ER cuts the protein free from its membrane-bound C terminus and simultaneously attaches the new C terminus to an amino group on a preassembled GPI intermediate. 3) The signal that specifies this modification is contained within the hydrophobic C-terminal sequence and a few amino acids adjacent to it on the lumenal side of the ER membrane; if this signal is added to other proteins, they too become modified in this way. Because of the covalently linked lipid anchor, the protein remains membrane-bound, with all of its amino acids exposed initially on the lumenal side of the ER and eventually on the cell exterior. 27
28 What happen to the newly synthesized in the ER lumen? Removing of signal sequences Folding of polypeptides Forming of disulfide bond Glycoprotein formation Play a key role in protein targeting 28
29 Glycosylation Adding of carbohydrate part into protein and there are 2 types of glycosylation 1. O-linked GalNac 2. N-linked GlcNac (Ser, Thr) (Asn) 29
30 30 Nelson & Cox, Lehninger Principles of Biochemistry, 4th ed., 2005
31 B. A. 31 Nelson & Cox, Lehninger Principles of Biochemistry, 4th ed., 2005
32 Process of N-glycosylation ER ER & Pre-Golgi Intermediates Pre-Golgi Intermediates & Golgi apparatus Transfer of lipid-liked Glc 3 Man 9 GlcNAc 2 to Asn in nascent polypeptides Removal of all three glucose residues by glucosidase I & II Transient reglucosylation by UDP-Glc: glycoprotein glucosyltransferase Removal of mannose residues by ER mannosidases Trimming of glucosylated inermediated by endomannosidase Golgi apparatus Removal of mannose residues by Golgi manosidase Elongation reaction by glycosyltransferase Adapted from Roth J. Chem. Rev. 2002, 102,
33 The role of N-linked glycosylation in ER protein folding Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell. 4th edition. New York: Garland Science; ) The ER-membrane-bound chaperone protein calnexin binds to incompletely folded proteins containing one terminal glucose on N-linked oligosaccharides, trapping the protein in the ER. 2) Removal of the terminal glucose by a glucosidase releases the protein from calnexin. 3) A glucosyl transferase is the crucial enzyme that determines whether the protein is folded properly or not: if the protein is still incompletely folded, the enzyme transfers a new glucose from UDP-glucose to the N-linked oligosaccharide, renewing the protein's affinity for calnexin and retaining it in the ER. 4) The cycle repeats until the protein has folded completely. Calreticulin functions similarly, except that it is a soluble ER resident protein. Another ER chaperone, ERp57 (not shown), collaborates with calnexin and calreticulin in retaining an incompletely folded protein in the ER. 33
34 The export and degradation of misfolded ER proteins Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell. 4th edition. New York: Garland Science; ) Misfolded soluble proteins in the ER lumen are translocated back into the cytosol, where they are deglycosylated, ubiquitylated, and degraded in proteasomes. 2) Misfolded membrane proteins follow a similar pathway. 3) Misfolded proteins are exported through the same type of translocator that mediated their import; accessory proteins that are associated with the translocator allow it to operate in the export direction. 34
35 O-glycosylation No consensus sequence for Ser and Thr Consensus for Hyl Gly X Hyl Y Arg Begins with GalNac transferase (Nacetylgalactosamine) Mannose common addition to core 35
36 Notes for glycosylation Usually be extracellular proteins or located at cell surface High structural information content molecular recognition Occurs along the secretory pathway Often stabilizes structure Difficult to get crystal structure for more than one or two carbohydrate residues 36
37 Utilization of different coats in vesicular traffic 37
38 The postulated role of SNAREs in guiding vesicular transport There are at least 20 different SNAREs in an animal cell, each associated with a particular membrane-enclosed organelles involved in the biosynthetic-secretory or endocytic pathway. These transmembrane proteins exist as complementary sets vesicle membrane SNAREs, called v-snares target membrane SNAREs, called t-snares, v-snaress and t-snares have characteristic helical domains. When a v-snares interacts with a t-snare, the helical domains of one wrap around the helical domains of the other to form stable trans-snare complexes, which lock the two membranes together. The specificity with which SNAREs interact determines the specificity of vesicle docking and fusion. SNAREs specify compartment identity and govern the orderly transfer of material during vesicle transport. 38
39 Transport from the ER to the Golgi apparatus is mediated by vesicular tubular cluster 1) Vesicular tubular clusters move along microtubules to carry proteins from the ER to the Golgi apparatus. 2) COPI coats mediate the budding of vesicles that return to the ER from these clusters. 3) The coats quickly disassemble after the vesicles have formed. 39
40 The retrieval pathway to the ER uses sorting signals (A) (B) The KDEL receptor present in vesicular tubular clusters and the Golgi apparatus, captures the soluble ER resident proteins and carries them in COPI-coated transport vesicles back to the ER. Upon binding its ligands in this low-ph environment, the KDEL receptor may change conformation, so as to facilitate its recruitment into budding COPIcoated vesicles. The retrieval of ER proteins begins in vesicular tubular clusters and continues from all parts of the Golgi apparatus. In the neutral-ph environment of the ER, the ER proteins dissociate from the KDEL receptor, which is then returned to the Golgi for reuse. 40
41 41
42 Oligosaccharide processing in the ER and the Golgi apparatus Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell. 4th edition. New York: Garland Science; Processing begins in the ER with the removal of the glucoses from the oligosaccharide initially transferred to the protein. A mannosidase in the ER membrane removes a specific mannose. Golgi mannosidase I removes three more mannoses and N-acetylglucosamine transferase I then adds an N-acetylglucosamine, which enables mannosidase II to remove two additional mannoses. This yields the final core of three mannoses that is present in a complex oligosaccharide. At this stage, the bond between the two N-acetylglucosamines in the core becomes resistant to attack by a highly specific endoglycosidase (Endo H). Since all later structures in the pathway are also Endo H-resistant, treatment with this enzyme is widely used to distinguish complex from high-mannose oligosaccharides. Additional N-acetylglucosamines, galactoses, and sialic acids are added. These final steps in the synthesis of a complex oligosaccharide occur in the cisternal compartments of the Golgi apparatus. Three types of glycosyl transferase enzymes act sequentially, using sugar substrates that have been activated by linkage to the indicated nucleotide. The membranes of the Golgi cisternae contain specific carrier proteins that allow each sugar nucleotide to enter in exchange for the nucleotide phosphates that are released after the sugar is attached to the protein on the lumenal face. 42
43 Albert B. et. al. Molecular Biology of the Cell, 4 th ed,
Protein Trafficking in the Secretory and Endocytic Pathways
Protein Trafficking in the Secretory and Endocytic Pathways The compartmentalization of eukaryotic cells has considerable functional advantages for the cell, but requires elaborate mechanisms to ensure
More informationPractice Exam 2 MCBII
1. Which feature is true for signal sequences and for stop transfer transmembrane domains (4 pts)? A. They are both 20 hydrophobic amino acids long. B. They are both found at the N-terminus of the protein.
More informationSummary of Endomembrane-system
Summary of Endomembrane-system 1. Endomembrane System: The structural and functional relationship organelles including ER,Golgi complex, lysosome, endosomes, secretory vesicles. 2. Membrane-bound structures
More informationProtein sorting (endoplasmic reticulum) Dr. Diala Abu-Hsasan School of Medicine
Protein sorting (endoplasmic reticulum) Dr. Diala Abu-Hsasan School of Medicine dr.abuhassand@gmail.com An overview of cellular components Endoplasmic reticulum (ER) It is a network of membrane-enclosed
More informationIntracellular Compartments and Protein Sorting
Intracellular Compartments and Protein Sorting Intracellular Compartments A eukaryotic cell is elaborately subdivided into functionally distinct, membrane-enclosed compartments. Each compartment, or organelle,
More informationMolecular Cell Biology Problem Drill 16: Intracellular Compartment and Protein Sorting
Molecular Cell Biology Problem Drill 16: Intracellular Compartment and Protein Sorting Question No. 1 of 10 Question 1. Which of the following statements about the nucleus is correct? Question #01 A. The
More informationTRANSPORT PROCESSES. 1b. moving proteins into membranes and organelles
1b. moving proteins into membranes and organelles SLIDE 1 A typical mammalian cell contains up to 10,000 different kinds of proteins. The vast majority of these proteins are synthesized by cytosolic ribosomes,
More informationMolecular Trafficking
SCBM 251 Molecular Trafficking Assoc. Prof. Rutaiwan Tohtong Department of Biochemistry Faculty of Science rutaiwan.toh@mahidol.ac.th Lecture outline 1. What is molecular trafficking? Why is it important?
More informationIntracellular vesicular traffic. B. Balen
Intracellular vesicular traffic B. Balen Three types of transport in eukaryotic cells Figure 12-6 Molecular Biology of the Cell ( Garland Science 2008) Endoplasmic reticulum in all eucaryotic cells Endoplasmic
More informationPROTEIN TRAFFICKING. Dr. SARRAY Sameh, Ph.D
PROTEIN TRAFFICKING Dr. SARRAY Sameh, Ph.D Overview Proteins are synthesized either on free ribosomes or on ribosomes bound to endoplasmic reticulum (RER). The synthesis of nuclear, mitochondrial and peroxisomal
More informationVesicle Transport. Vesicle pathway: many compartments, interconnected by trafficking routes 3/17/14
Vesicle Transport Vesicle Formation Curvature (Self Assembly of Coat complex) Sorting (Sorting Complex formation) Regulation (Sar1/Arf1 GTPases) Fission () Membrane Fusion SNARE combinations Tethers Regulation
More informationendomembrane system internal membranes origins transport of proteins chapter 15 endomembrane system
endo system chapter 15 internal s endo system functions as a coordinated unit divide cytoplasm into distinct compartments controls exocytosis and endocytosis movement of molecules which cannot pass through
More information1. to understand how proteins find their destination in prokaryotic and eukaryotic cells 2. to know how proteins are bio-recycled
Protein Targeting Objectives 1. to understand how proteins find their destination in prokaryotic and eukaryotic cells 2. to know how proteins are bio-recycled As a protein is being synthesized, decisions
More informationEssential Cell Biology
Alberts Bray Hopkin Johnson Lewis Raff Roberts Walter Essential Cell Biology FOURTH EDITION Chapter 15 Intracellular Compartments and Protein Transport Copyright Garland Science 2014 CHAPTER CONTENTS MEMBRANE-ENCLOSED
More informationCell Quality Control. Peter Takizawa Department of Cell Biology
Cell Quality Control Peter Takizawa Department of Cell Biology Cellular quality control reduces production of defective proteins. Cells have many quality control systems to ensure that cell does not build
More informationCELL BIOLOGY - CLUTCH CH INTRACELLULAR PROTEIN TRANSPORT.
!! www.clutchprep.com CONCEPT: MEMBRANE ENCLOSED ORGANELLES Table of eukaryotic organelles and their functions Organelle Function % volume of cell Cytosol Aqueous fluid where metabolic pathways and chemical
More informationHomework Hanson section MCB Course, Fall 2014
Homework Hanson section MCB Course, Fall 2014 (1) Antitrypsin, which inhibits certain proteases, is normally secreted into the bloodstream by liver cells. Antitrypsin is absent from the bloodstream of
More informationBIOL 4374/BCHS 4313 Cell Biology Exam #2 March 22, 2001
BIOL 4374/BCHS 4313 Cell Biology Exam #2 March 22, 2001 SS# Name This exam is worth a total of 100 points. The number of points each question is worth is shown in parentheses. Good luck! 1. (2) In the
More informationChapter 13: Vesicular Traffic
Chapter 13: Vesicular Traffic Know the terminology: ER, Golgi, vesicle, clathrin, COP-I, COP-II, BiP, glycosylation, KDEL, microtubule, SNAREs, dynamin, mannose-6-phosphate, M6P receptor, endocytosis,
More information17/01/2017. Protein trafficking between cell compartments. Lecture 3: The cytosol. The mitochondrion - the power plant of the cell
ell biology 2017 version 13/1 2017 ote endosome vs lysosome handout Lecture 3: Text book Alberts et al.: hapter 12-14 (Topics covered by the lecture) A lot of reading! Focus on principles ell Biology interactive
More informationMolecular Cell Biology - Problem Drill 17: Intracellular Vesicular Traffic
Molecular Cell Biology - Problem Drill 17: Intracellular Vesicular Traffic Question No. 1 of 10 1. Which of the following statements about clathrin-coated vesicles is correct? Question #1 (A) There are
More information2013 John Wiley & Sons, Inc. All rights reserved. PROTEIN SORTING. Lecture 10 BIOL 266/ Biology Department Concordia University. Dr. S.
PROTEIN SORTING Lecture 10 BIOL 266/4 2014-15 Dr. S. Azam Biology Department Concordia University Introduction Membranes divide the cytoplasm of eukaryotic cells into distinct compartments. The endomembrane
More information1. This is the location where N-linked oligosaccharide is initially synthesized and attached to glycoproteins.
Biology 4410 Name Spring 2006 Exam 2 A. Multiple Choice, 2 pt each Pick the best choice from the list of choices, and write it in the space provided. Some choices may be used more than once, and other
More informationZool 3200: Cell Biology Exam 4 Part I 2/3/15
Name: Key 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 informationEndomembrane system 11/1/2018. Endomembrane System. Direct physical continuity. Transfer of membrane segments as vesicles. Outer Nuclear envelope
Endomembrane system Endomembrane System Outer Nuclear envelope Direct physical continuity Transfer of membrane segments as vesicles Endoplasmic reticulum BUT membranes are not identical in structure and
More informationLecture Readings. Vesicular Trafficking, Secretory Pathway, HIV Assembly and Exit from Cell
October 26, 2006 1 Vesicular Trafficking, Secretory Pathway, HIV Assembly and Exit from Cell 1. Secretory pathway a. Formation of coated vesicles b. SNAREs and vesicle targeting 2. Membrane fusion a. SNAREs
More information1. endoplasmic reticulum This is the location where N-linked oligosaccharide is initially synthesized and attached to glycoproteins.
Biology 4410 Name Spring 2006 Exam 2 A. Multiple Choice, 2 pt each Pick the best choice from the list of choices, and write it in the space provided. Some choices may be used more than once, and other
More informationMoving Proteins into Membranes and Organelles
13 Moving Proteins into Membranes and Organelles Review the Concepts 1. In eukaryotes, protein translocation across the endoplasmic reticulum (ER) membrane is most commonly cotranslational; it can also
More informationLecture 6 - Intracellular compartments and transport I
01.25.10 Lecture 6 - Intracellular compartments and transport I Intracellular transport and compartments 1. Protein sorting: How proteins get to their appropriate destinations within the cell 2. Vesicular
More informationLecture 4. Protein Translocation & Nucleocytoplasmic Transport
Lecture 4 Protein Translocation & Nucleocytoplasmic Transport Chapter 12 MBoC (5th Edition) Alberts et al. Reference paper: Tran and Wente, Cell 125, 1041-1053, 2006 2/6/2013 1 A Model for How a Soluble
More informationThe endoplasmic reticulum is a network of folded membranes that form channels through the cytoplasm and sacs called cisternae.
Endoplasmic reticulum (ER) The endoplasmic reticulum is a network of folded membranes that form channels through the cytoplasm and sacs called cisternae. Cisternae serve as channels for the transport of
More informationI. Membrane Proteins II. Intracellular Compartments III. Protein Translocation
Lecture 3 I. Membrane Proteins II. Intracellular Compartments III. Protein Translocation Ref: MBoC (5th Edition), Alberts Johnson Lewis Raff Roberts Walter Chapter 10 Membrane Structure Chapter 12 Intracellular
More informationIntroduction and protein sorting
Introduction and protein sorting Membrane proteins Major components of cells Nucleic acids Carbohydrates Proteins Lipids (50% of mass of plasma membranes, 30% of mitochondrial membranes, 80% of myelin
More informationMechanism of Vesicular Transport
Mechanism of Vesicular Transport Transport vesicles play a central role in the traffic of molecules between different membrane-enclosed enclosed compartments. The selectivity of such transport is therefore
More informationBIOL 158: BIOLOGICAL CHEMISTRY II
BIOL 158: BIOLOGICAL CHEMISTRY II Lecture 1: Membranes Lecturer: Christopher Larbie, PhD Introduction Introduction Cells and Organelles have membranes Membranes contain lipids, proteins and polysaccharides
More informationChapter 6. Antigen Presentation to T lymphocytes
Chapter 6 Antigen Presentation to T lymphocytes Generation of T-cell Receptor Ligands T cells only recognize Ags displayed on cell surfaces These Ags may be derived from pathogens that replicate within
More informationSignificance and Functions of Carbohydrates. Bacterial Cell Walls
Biochemistry 462a - Carbohydrate Function Reading - Chapter 9 Practice problems - Chapter 9: 2, 4a, 4b, 6, 9, 10, 13, 14, 15, 16a, 17; Carbohydrate extra problems Significance and Functions of Carbohydrates
More informationMolecular Cell Biology 5068 In Class Exam 1 October 3, 2013
Molecular Cell Biology 5068 In Class Exam 1 October 3, 2013 Exam Number: Please print your name: Instructions: Please write only on these pages, in the spaces allotted and not on the back. Write your number
More informationI. Fluid Mosaic Model A. Biological membranes are lipid bilayers with associated proteins
Lecture 6: Membranes and Cell Transport Biological Membranes I. Fluid Mosaic Model A. Biological membranes are lipid bilayers with associated proteins 1. Characteristics a. Phospholipids form bilayers
More informationA. Major parts 1. Nucleus 2. Cytoplasm a. Contain organelles (see below) 3. Plasma membrane (To be discussed in Cellular Transport Lecture)
Lecture 5: Cellular Biology I. Cell Theory Concepts: 1. Cells are the functional and structural units of living organisms 2. The activity of an organism is dependent on both the individual and collective
More informationLecture 2 I. Membrane Proteins II. Intracellular Compartments
Lecture 2 I. Membrane Proteins II. Intracellular Compartments Ref: MBoC (5th Edition), Alberts Johnson Lewis Raff Roberts Walter Chapter 10 Membrane Structure Chapter 12 Intracellular Compartments and
More informationCELLS. Cells. Basic unit of life (except virus)
Basic unit of life (except virus) CELLS Prokaryotic, w/o nucleus, bacteria Eukaryotic, w/ nucleus Various cell types specialized for particular function. Differentiation. Over 200 human cell types 56%
More informationEndoplasmic Reticulum
Endoplasmic Reticulum What s ER? How is ER? Why is ER? definition description functions Nissl s bodies neurons Berg s bodies hepatocytes Organelle structure histocytochemical evidences Ergastoplasm pancreatic
More informationAdvanced Cell Biology. Lecture 33
Advanced Cell Biology. Lecture 33 Alexey Shipunov Minot State University April 22, 2013 Shipunov (MSU) Advanced Cell Biology. Lecture 33 April 22, 2013 1 / 38 Outline Questions and answers Intracellular
More informationScantron Instructions
BIOLOGY 1A MIDTERM # 1 February 17 th, 2012 NAME SECTION # DISCUSSION GSI 1. Sit every other seat and sit by section number. Place all books and paper on the floor. Turn off all phones, pagers, etc. and
More informationAP Biology
Tour of the Cell (1) 2007-2008 Types of cells Prokaryote bacteria cells - no organelles - organelles Eukaryote animal cells Eukaryote plant cells Cell Size Why organelles? Specialized structures - specialized
More informationGlycoprotein Maturation and Quality Control in the Endoplasmic Reticulum Dr. Daniel Hebert
Glycoprotein Maturation and Quality Control in the Endoplasmic Reticulum Department of Biochemistry and Molecular Biology University of Massachusetts, USA 1 Intracellular protein trafficking Plasma membrane
More informationProblem Set 5, 7.06, Spring of 13
Problem Set 5, 7.06, Spring 2003 1 of 13 1. In order to please your demanding thesis advisor, you've completed an extensive fractionation and biochemical purification of proteins localized to the mitochondria,
More informationIntracellular Vesicular Traffic Chapter 13, Alberts et al.
Intracellular Vesicular Traffic Chapter 13, Alberts et al. The endocytic and biosynthetic-secretory pathways The intracellular compartments of the eucaryotic ell involved in the biosynthetic-secretory
More informationProtein Modification Overview DEFINITION The modification of selected residues in a protein and not as a component of synthesis
Lecture Four: Protein Modification & Cleavage [Based on Chapters 2, 9, 10 & 11 Berg, Tymoczko & Stryer] (Figures in red are for the 7th Edition) (Figures in Blue are for the 8th Edition) Protein Modification
More informationAP Biology Book Notes Chapter 4: Cells v Cell theory implications Ø Studying cell biology is in some sense the same as studying life Ø Life is
AP Biology Book Notes Chapter 4: Cells v Cell theory implications Ø Studying cell biology is in some sense the same as studying life Ø Life is continuous v Small cell size is becoming more necessary as
More informationAmino acids. Side chain. -Carbon atom. Carboxyl group. Amino group
PROTEINS Amino acids Side chain -Carbon atom Amino group Carboxyl group Amino acids Primary structure Amino acid monomers Peptide bond Peptide bond Amino group Carboxyl group Peptide bond N-terminal (
More informationMain differences between plant and animal cells: Plant cells have: cell walls, a large central vacuole, plastids and turgor pressure.
Main differences between plant and animal cells: Plant cells have: cell walls, a large central vacuole, plastids and turgor pressure. Animal cells have a lysosome (related to vacuole) and centrioles (function
More informationCell wall components:
Main differences between plant and animal cells: Plant cells have: cell walls, a large central vacuole, plastids and turgor pressure. The Cell Wall The primary cell wall is capable of rapid expansion during
More informationChapt. 10 Cell Biology and Biochemistry. The cell: Student Learning Outcomes: Describe basic features of typical human cell
Chapt. 10 Cell Biology and Biochemistry Cell Chapt. 10 Cell Biology and Biochemistry The cell: Lipid bilayer membrane Student Learning Outcomes: Describe basic features of typical human cell Integral transport
More informationChapter 13 Moving Proteins into Membranes and Organelles
Chapter 13 Moving Proteins into Membranes and Organelles Chapter 13 Moving Proteins into Membranes and Organelles 13.1 Targeting Proteins To and Across the ER Membrane 13.2 Insertion of Membrane Proteins
More informationName: Multiple choice questions. Pick the BEST answer (2 pts ea)
Exam 1 202 Oct. 5, 1999 Multiple choice questions. Pick the BEST answer (2 pts ea) 1. The lipids of a red blood cell membrane are all a. phospholipids b. amphipathic c. glycolipids d. unsaturated 2. The
More informationChapter 31. Completing the Protein Life Cycle: Folding, Processing and Degradation. Biochemistry by Reginald Garrett and Charles Grisham
Chapter 31 Completing the Protein Life Cycle: Folding, Processing and Degradation Biochemistry by Reginald Garrett and Charles Grisham Essential Question How are newly synthesized polypeptide chains transformed
More informationInsulin mrna to Protein Kit
Insulin mrna to Protein Kit A 3DMD Paper BioInformatics and Mini-Toober Folding Activity Student Handout www.3dmoleculardesigns.com Insulin mrna to Protein Kit Contents Becoming Familiar with the Data...
More informationThe Cell Organelles. Eukaryotic cell. The plasma membrane separates the cell from the environment. Plasma membrane: a cell s boundary
Eukaryotic cell The Cell Organelles Enclosed by plasma membrane Subdivided into membrane bound compartments - organelles One of the organelles is membrane bound nucleus Cytoplasm contains supporting matrix
More informationCell morphology. Cell organelles structure and function. Chapter 1: UNIT 1. Dr. Charushila Rukadikar
UNIT 1 Cell morphology Cell organelles structure and function Chapter 1: Dr. Charushila Rukadikar Assistant Professor Department Of Physiology ZMCH, Dahod Physiology The science that is concerned with
More information10/13/11. Cell Theory. Cell Structure
Cell Structure Grade 12 Biology Cell Theory All organisms are composed of one or more cells. Cells are the smallest living units of all living organisms. Cells arise only by division of a previously existing
More informationDon t Freak Out. Test on cell organelle on Friday!
Cell Structure 1 Don t Freak Out Test on cell organelle on Friday! This test should be a buffer test and help raise your overall test score. All information will come from this week! 2 Cells Provide Compartments
More information1- Which of the following statements is TRUE in regards to eukaryotic and prokaryotic cells?
Name: NetID: Exam 3 - Version 1 October 23, 2017 Dr. A. Pimentel Each question has a value of 4 points and there are a total of 160 points in the exam. However, the maximum score of this exam will be capped
More informationMr. Powner Biology Cell Structure & Function Quiz Image Guide. Do NOT Write on this page. It is an Image guide for test questions.
Mr. Powner Biology Cell Structure & Function Quiz Prompts 1. The cell s managing structure; it contains most of the cell s genetic material (DNA, which stores information used to make proteins for cell
More informationSteps at which eukaryotic gene expression can be controlled. Cell 7.5
Steps at which eukaryotic gene expression can be controlled Cell 7.5 Protein Variability and Protein Activity Control Aminoacid sequence Three-dimensional shape (conformation) Function Protein processing
More informationChapter 1: Vesicular traffic. Biochimica cellulare parte B 2017/18
Chapter 1: Vesicular traffic Biochimica cellulare parte B 2017/18 Major Protein-sorting pathways in eukaryotic cells Secretory and endocytic pathways Unifying principle governs all protein trafficking
More informationRenata Schipp Medical Biology Department
Renata Schipp Medical Biology Department Deffinition of cell The cell is the smallest structural and functional unit of all known living organisms The cell was discovered by Robert Hooke in 1665 and also
More informationCytosol the fluid Cytoplasm cell interior, everything outside the nucleus but within the cell membrane, includes the organelles, cytosol, and
Cell Organelles Plasma Membrane comprised of a phospholipid bilayer and embedded proteins Outer surface has oligosaccharides separates the cells s contents from its surroundings Cytosol the fluid Cytoplasm
More informationIntroduction. Biochemistry: It is the chemistry of living things (matters).
Introduction Biochemistry: It is the chemistry of living things (matters). Biochemistry provides fundamental understanding of the molecular basis for the function and malfunction of living things. Biochemistry
More informationREGULATION OF ENZYME ACTIVITY. Medical Biochemistry, Lecture 25
REGULATION OF ENZYME ACTIVITY Medical Biochemistry, Lecture 25 Lecture 25, Outline General properties of enzyme regulation Regulation of enzyme concentrations Allosteric enzymes and feedback inhibition
More informationCellular functions of protein degradation
Protein Degradation Cellular functions of protein degradation 1. Elimination of misfolded and damaged proteins: Environmental toxins, translation errors and genetic mutations can damage proteins. Misfolded
More informationCellular compartments
Cellular compartments 1. Cellular compartments and their function 2. Evolution of cellular compartments 3. How to make a 3D model of cellular compartment 4. Cell organelles in the fluorescent microscope
More information/ The following functional group is a. Aldehyde c. Carboxyl b. Ketone d. Amino
Section A: Multiple Choice Select the answer that best answers the following questions. Please write your selected choice on the line provided, in addition to circling the answer. /25 1. The following
More informationThe Cell. Biology 105 Lecture 4 Reading: Chapter 3 (pages 47 62)
The Cell Biology 105 Lecture 4 Reading: Chapter 3 (pages 47 62) Outline I. Prokaryotic vs. Eukaryotic II. Eukaryotic A. Plasma membrane transport across B. Main features of animal cells and their functions
More informationStudent name ID # 2. (4 pts) What is the terminal electron acceptor in respiration? In photosynthesis?
1. Membrane transport. A. (4 pts) What ion couples primary and secondary active transport in animal cells? What ion serves the same function in plant cells? 2. (4 pts) What is the terminal electron acceptor
More informationLecture 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 informationStructure & Function of Cells
Anatomy & Physiology 101-805 Unit 4 Structure & Function of Cells Paul Anderson 2011 Anatomy of a Generalised Cell Attached or bound ribosomes Cilia Cytosol Centriole Mitochondrion Rough endoplasmic reticulum
More informationBIO 5099: Molecular Biology for Computer Scientists (et al)
BIO 5099: Molecular Biology for Computer Scientists (et al) Lecture 15: Being a Eukaryote: From DNA to Protein, A Tour of the Eukaryotic Cell. Christiaan van Woudenberg Being A Eukaryote Basic eukaryotes
More informationOctober 26, Lecture Readings. Vesicular Trafficking, Secretory Pathway, HIV Assembly and Exit from Cell
October 26, 2006 Vesicular Trafficking, Secretory Pathway, HIV Assembly and Exit from Cell 1. Secretory pathway a. Formation of coated vesicles b. SNAREs and vesicle targeting 2. Membrane fusion a. SNAREs
More informationZool 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 informationBIOLOGY 111. CHAPTER 3: The Cell: The Fundamental Unit of Life
BIOLOGY 111 CHAPTER 3: The Cell: The Fundamental Unit of Life The Cell: The Fundamental Unit of Life Learning Outcomes 3.1 Explain the similarities and differences between prokaryotic and eukaryotic cells
More informationRenáta Schipp Gergely Berta Department of Medical Biology
The cell III. Renáta Schipp Gergely Berta Department of Medical Biology Size and Biology Biology is a visually rich subject many of the biological events and structures are smaller than the unaided human
More informationAP 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 informationThe further from the nucleus, the higher the electron s energy Valence shell electrons participate in biological reactions
Chemistry of Life Revision: The further from the nucleus, the higher the electron s energy Valence shell electrons participate in biological reactions Atoms exchange electrons with other elements to form
More informationSBI3U7 Cell Structure & Organelles. 2.2 Prokaryotic Cells 2.3 Eukaryotic Cells
SBI3U7 Cell Structure & Organelles 2.2 Prokaryotic Cells 2.3 Eukaryotic Cells No nucleus Prokaryotic Cells No membrane bound organelles Has a nucleus Eukaryotic Cells Membrane bound organelles Unicellular
More informationCellular Biochemistry
Cellular Biochemistry Fall Semester 2013 Sept. 23 Benoit Kornmann Institute of Biochemistry Introduction to biological membranes General functions and properties Membrane lipids Physical properties Distribution/asymmetry
More informationCell Structure and Function. Biology 12 Unit 1 Cell Structure and Function Inquiry into Life pages and 68-69
Cell Structure and Function Biology 12 Unit 1 Cell Structure and Function Inquiry into Life pages 45 59 and 68-69 Assignments for this Unit Pick up the notes/worksheet for this unit and the project There
More informationA TOUR OF THE CELL 10/1/2012
A TOUR OF THE CELL Chapter 6 KEY CONCEPTS: Eukaryotic cells have internal membranes that compartmentalize their functions The eukaryotic cell s genetic instructions are housed in the nucleus and carried
More informationGlycosaminoglycans: Anionic polysaccharide chains made of repeating disaccharide units
Glycosaminoglycans: Anionic polysaccharide chains made of repeating disaccharide units Glycosaminoglycans present on the animal cell surface and in the extracellular matrix. Glycoseaminoglycans (mucopolysaccharides)
More informationExplain that each trna molecule is recognised by a trna-activating enzyme that binds a specific amino acid to the trna, using ATP for energy
7.4 - Translation 7.4.1 - Explain that each trna molecule is recognised by a trna-activating enzyme that binds a specific amino acid to the trna, using ATP for energy Each amino acid has a specific trna-activating
More informationCell Physiology Final Exam Fall 2008
Cell Physiology Final Exam Fall 2008 Guys, The average on the test was 69.9. Before you start reading the right answers please do me a favor and remember till the end of your life that GLUCOSE TRANSPORT
More informationCell Membranes. Dr. Diala Abu-Hassan School of Medicine Cell and Molecular Biology
Cell Membranes Dr. Diala Abu-Hassan School of Medicine Dr.abuhassand@gmail.com Cell and Molecular Biology Organelles 2Dr. Diala Abu-Hassan Membrane proteins Major components of cells Nucleic acids DNA
More informationFatty acid breakdown
Fatty acids contain a long hydrocarbon chain and a terminal carboxylate group. Most contain between 14 and 24 carbon atoms. The chains may be saturated or contain double bonds. The complete oxidation of
More information10/5/2015. Cell Size. Relative Rate of Reaction
The Cell Biology 102 Fundamental unit of life Smallest unit that displays all the basic elements of life Lecture 5: Cells Cell Theory 1. All living things are made of one or more cells Cell Theory 2. The
More informationCells. Variation and Function of Cells
Cells Variation and Function of Cells Cell Theory states that: 1. All living things are made of cells 2. Cells are the basic unit of structure and function in living things 3. New cells are produced from
More information7.06 Cell Biology EXAM #3 April 24, 2003
7.06 Spring 2003 Exam 3 Name 1 of 8 7.06 Cell Biology EXAM #3 April 24, 2003 This is an open book exam, and you are allowed access to books and notes. Please write your answers to the questions in the
More informationEndomembrane system, *Chloroplasts, *Mitochondria. *Learn these from text/connect1. Fertilization of a human cell
Key Concepts: - Cells are the Basic Unit of Life Cell Theory, Surface to Volume - 2 Cell Types Prokaryotic, Eukaryotic - Cell Membrane Membrane Structure - Cell Organelles Endomembrane system, *Chloroplasts,
More informationSection 6. Junaid Malek, M.D.
Section 6 Junaid Malek, M.D. The Golgi and gp160 gp160 transported from ER to the Golgi in coated vesicles These coated vesicles fuse to the cis portion of the Golgi and deposit their cargo in the cisternae
More information/searchlist/6850.html Tour of the Cell 1
http://www.studiodaily.com/main /searchlist/6850.html Tour of the Cell 1 2011-2012 Cytology: science/study of cells To view cells: Light microscopy resolving power: measure of clarity Electron microscopy
More information