Post-Translational Events II ER & Golgi Processes.

Slides:



Advertisements
Similar presentations
ESSENTIALS OF GLYCOBIOLOGY LECTURE 14 DEGRADATION AND TURNOVER OF GLYCOCONJUGATES Hud Freeze.
Advertisements

Protein sorting and the Golgi apparatus
Carbohydrates: Oligosaccahrdes and Polysaccharides.
Essentials of Glycobiology Lecture 5 April 6, 2004 Ajit Varki N-Glycans Asparagine (N)-linked oligosaccharides N-linked Glycans N-linked Sugar Chains.
Protein Sorting & Transport Paths of Protein Trafficking Nuclear Protein Transport Mitochondrial & Chloroplast Transport Experimental Systems Overview.
Biochemistry of cellular organelles Lectures: 1. Membrane channels; 2. Membrane transporters; 3. Soluble lipid/metabolite-transfer proteins; 4. Mitochondria.
Cell and Molecular Biology Behrouz Mahmoudi Cell Organelles-1 1.
Intracellular Compartments
Protein Sorting ISAT 351, Spring 2004 College of Integrated Science and Technology James Madison University.
Biochemistry- Ch 11. Carbohydrates (Cont.) 阮雪芬 NTUT Nov 18, 2002.
Review For Final I. Should I take the final? Can’t hurt you Calculate your average and determine what you need to change your grade.
Glycoconjugates Carbohydrates covalently linked to a protein or lipid act as informational carrier in: cell-cell recognition, cell-cell adhesion, cell.
Vesicular Traffic II. Endocytic and secretory pathways red = secretory green = endocytic blue = recycling.
Cytoplasmic Membrane Systems II Lecture 12. How Do Proteins Get Imported Into Membrane Enclosed Organelles? Import Requires Input of Energy to Occur!
Vesicular Transport III. N-linked glycosylation because sugar is added to N of asparagine. original precursor oligosaccharide added to most proteins in.
Chapter 8 (part2) Carbohydrates: oligo- and polysaccharides.
Lecture 7 - Intracellular compartments and transport II
Protein modification and trafficking. There are two types of glycosylation N-glycosidic bonds form via an N-glycosidic linkage is through the amide.
Protein Secretion Sarah Thomas. Secretory Pathway n Ribosomes that are synthesizing proteins and bear an ER signal sequence bind to rough ER. n Once transcription.
Protein Biosynthesis -2 By Amr S. Moustafa, M.D.; Ph.D.
ROUGH ENDOPLASMIC RETICULUM
Extra credit for Midterm 2
Chapter 25 Protein trafficking Introduction 25.2 Oligosaccharides are added to proteins in the ER and Golgi 25.3 The Golgi stacks are polarized.
1. Membrane Organization and the Plasma Membrane 1a. The lipid bilayer.
Posttranslational Modification of Proteins
CHAPTER 6 SYSTEMS BIOLOGY OF CELL ORGANIZATION
Dental Biochemistry Lecture 45 Carol Lutz, PhD Complex Carbohydrates: Glycoproteins and Proteoglycans.
SYNTHESIS OF GLYCOPROTEINS Dr. Nasim AP BIOCHEMISTRY.
Chapter 3 Membrane targeting of proteins By D. Thomas Rutkowski & Vishwanath R. Lingappa.
Protein folding,maturation & targeting. Secretory pathway: signal peptide recognition.
BIOL 200 (Section 921) Lecture # 9, 10 June 29/30, 2006 Readings ECB (2nd ed.) Chapter 15 (Whole chapter): Introduction, pp ; Protein Sorting pp.
Protein targeting to organelles 1.From the birth place to the destination— general principles 1)The problem: One place to make protein but many destinations—how.
Molecular and Cellular Biochemistry 2. ER- protein modifications
SYNTHESIS OF GLYCOPROTEINS
Golgi complex BIOLOGY, Faculty of Medicine and Dentistry László KŐHIDAI, PhD., Assoc. Prof. Department of Genetics, Cell- and Immunobiology.
8. Protein Synthesis and Protein Processing a). Ribosome structure b). Protein synthesis i). Initiation of protein synthesis ii). Peptide bond formation;
Cell and Molecular Biology Behrouz Mahmoudi Cell organelles-2 1.
Fates of Proteins in Cells See also pages in Goodman.
Chapter 8 (part2) Carbohydrates: oligo- and polysaccharides.
ER and Golgi: Working Together! Mr. Nichols PHHS.
Red Blood cell membrane
© 2012 Pearson Education, Inc. Lectures by Kathleen Fitzpatrick Simon Fraser University Membranes: Their Structure, Function, and Chemistry Chapter 7.
GLYCOPROTEINS Dr Amina Tariq Biochemistry. Glycoproteins Glycoproteins are proteins that contain oligosaccharide (glycan) chains covalently attached to.
Golgi complex BIOLOGY, Faculty of Medicine and Dentistry László KŐHIDAI, PhD., Assoc. Prof. Department of Genetics, Cell- and Immunobiology.
Molecular Biology of the Cell
Chapter 12 Intracellular Compartments and Protein Sorting.
 Golgi apparatus or golgi complex or simple Golgi is an organelle found in most of the eukaryotic cells.  It was one of the first organelle to be.
GOLGI APPARATUs.
Copyright (c) by W. H. Freeman and Company 17.3 The rough ER is an extensive interconnected series of flattened sacs Figure
PACKAGING, TRANSPORTING and EXPORTING
ENDOPLASMIC RETICULUM Submitted by Dr Madhurima Sharma.
 The endoplasmic reticulum (ER) in the cells of eukaryotic organisms is an interconnected network of flattened, membrane-enclosed sacs or tubes known.
Biosynthesis of a Secretory Protein The starred words are made of membranes. This means that they are all composed of phospholipids Ribosome- *Rough Endoplasmic.
Cytoplasmic membranes-1 Unit objective: To understand that materials in cell are shuttled from one part to another via an extensive membrane network.
Protein targeting or Protein sorting Refer Page 1068 to 1074 Principles of Biochemistry by Lehninger & Page 663 Baltimore Mol Cell Biology.
The ER and Golgi Modify & Sort Proteins
Post-Translational Events I Protein Trafficking
Protein Sorting & Transport
Synthesis and Structure of Major Glycan Classes
Vesicular Trafficking
Intracellular Vesicular Traffic
Post Translational Modifications of Proteins
Fig
Intracellular Vesicular Traffic
Glycosyltransferases and Glycosidases
Hudson H. Freeze, Jessica X. Chong, Michael J. Bamshad, Bobby G. Ng 
Glycoproteins and mucins
بسم الله الرحمن الرحيم.
Glycosylation Events and Types
Red Blood cell membrane
Presentation transcript:

Post-Translational Events II ER & Golgi Processes

Rough Endoplasmic Reticulum

Glycolsylation O-linked – serine, threonine, hydroxylysine (collagen) N-linked - asparagine The sugars –GalNac – N-acetylgalactosamine –GlcNac – N-acetylglucosamine –NANA – N-acetylneuraminic acid (sialic acid) –Gal – galactose –Glc – glucose –Man – mannose –Fuc – fucose –Dolicholpyrophosphoryl oligosaccharide All sugars are linked to nucleoside mono- or diphosphate –UDP-gal, UDP-GalNac, UDP-GlcNac –GDP-man –CMP-NANA –Dolichol pyrophosphate

Glyco-nucleoside Phosphates CH 3 C(CH 3 )=CHCH 2 CH 2 C(CH 3 )=CHCH CH 2 CH(CH 3 )CH 2 CH 2 OPO 3 Dolichol phosphate

O-linked Glycosylation Small chains of sugars N-acetylgalactosamine (GalNac) is first sugar on S orT –GalNac transferase in ER and cis-golgi Additional sugars added in cis, medial and trans- golgi –Gal added by galactosyl transferase –NANA added last Each sugar addition is catalyzed by specific enzyme

N-linked Glycosylation Initial step in ER Dolichol pyrophosphoryl oligosaccharide –14 sugar moiety attached to dolichol pyrophosphate (GalNac) 2 Man 9 Glc 3 –Dolichol phosphate in ER membrane –Sugars added by cytostolic glycosyltransferases –Moiety flips in ER membrane to face lumen –Transferred to asparagine by oligosaccharyl transferase (oligosaccharide-protein transferase) –Target sequence N-X-S and N-X-T (X = P) Subsequent remodeling of sugar moiety in ER & golgi N-linked chains very long and extensively branched

O- & N-linked Oligosaccharide Chains

N-linked Glycolsylation

GPI – Linkages GPI – linked proteins are attached to GPI in ER –GPI in ER membrane –C-term of protein attached to sugar residue on phosphatidyl inositol GPI linked protein will be attached to outer leaflet of plasma membrane

Protein Folding Occurs in ER Lumen

Misfolded Proteins Reverse Translocate to Proteasome

Unique Signaling from ER to Make More ER Pathway activated by stresses that result in more unfolded proteins –heat –unfavorable pHs

On to the Golgi

Processing in the Golgi Oligosaccharide modifications Sorting to exocytic vesicles, lysosomes and ER Proteolytic processing

Modification of N-linked Oligosaccharides As glycosylated protein moves through ER Glc is removed In cis Golgi, some Man is removed In medial golgi, GlcNac is added In trans-golgi, Gal and NANA are added CISTRANS

Mannose-6-Phosphate is Lysosomal Targeting Signal

Proteolytic Processing

Sterol & Lipid Biosynthesis Phospholgycerides in ER Sphingolipids in Golgi Lipid profile asymmetry established via phospholipid exchange proteins and selective vesicular transport due to association between carrier proteins and certain lipid types

Regulation of HMG-CoA Reductase