Vesicular transport

Vesicular transport

1. VESICULAR TRANSPORT

2. INTRODUCTION bubble-like membranous structure that stores and transports cellular products, and digests metabolic wastes within the cell; an intracellular membranous sac that is separated from the  cytosol by at least one lipid bilayer . Secretory Vesicles Transport Vesicles Storage Vesicles

3. INTRODUCTION Transport across but not through the membrane Mode of transport of macromolecules Requires metabolic energy but is independent of concentration gradient

4. CATEGORIES ENDOCYTOSIS EXOCYTOSIS TRANSCYTOSIS

5. ENDOCYTOSIS TYPES Phagocytosis - cell eating Pinocytosis - cell drinking Receptor-mediated

6. ENDOCYTOSIS Mechanisms : Constitutive Pathway Clathrin -mediated Pathway internalization of many receptors and the ligands bound to them—including, for example, nerve growth factor and low-density lipoproteins

7. Clathrin -mediated endocytosis Clathrin coated vesicles – COP I & COP II Clathrin Adaptor Proteins Dynamin Pinchase

8. Clathrin -mediated endocytosis

9. EXOCYTOSIS Non-Constitutive / Regulated Pathway Constitutive Pathway Exocytosis-Endocytosis coupling maintains the surface area of the cell at its normal size.

10. INTRA CELLULAR VESICULAR TRAFFIC Biosynthetic- Secretory pathway Endocytotic pathway Retrieval pathways

11. Vesicular traffic occurs in an orderly fashion Selective & Specific Rab proteins SNARE proteins

12. Rab Proteins

13. SNARE Proteins – mediate vescile fusion V-SNAREs – Docking proteins T-SNAREs – Latch proteins

14. APPLIED ASPECTS Botulism & Tetanus AUTOPHAGY or AUTOPHAGOCYTOSIS

15. APPLIED ASPECTS FAMILIAL HYPERCHOLESTEROLEMIA

16. THANK YOU A colorized scanning electron microscope picture of a nerve ending that has been broken open to reveal the synaptic vesicles (orange and blue) beneath the cell membrane.