L8 vesicle transport_2024_25 - Copy

Vesicle Transport: Exocytosis and Endocytosis

General Information

  • Instructor: Dr. Sarah Bailey

  • Office: 27AY04

  • Student Consultation Hours:

    • Week 3: Thursday, 12th October, 12:45 - 13:45

    • Week 4: Tuesday, 15th October, 12:45 - 13:45

Learning Outcomes

  • Coat Proteins: Understand the distinct roles of COPI, COPII, and clathrin in vesicle budding, specifically how these proteins coat vesicles during transportation between cellular compartments.

  • Vesicle Release: Describe the mechanism by which the GTPase dynamin facilitates vesicle release from donor membranes by forming a constricting collar at the neck of the vesicle.

  • SNARE Proteins: Explain the importance of SNARE proteins in vesicle fusion and selection, including their structural diversity and how they mediate the specificity of vesicle docking.

  • Constitutive Secretory Pathway: Provide examples of proteins typically transported via this pathway, such as collagen and growth factors, and discuss its overall significance in maintaining cellular function.

  • Vesicle Modifications: Discuss modifications that occur within secretory vesicles, including post-translational modifications and packaging of regulatory molecules.

  • Regulated Exocytosis: Identify specific cell types (e.g., pancreatic beta cells) and secreted proteins involved (such as insulin), including the physiological triggers for vesicle fusion.

  • Endocytosis: Explain the necessity of membrane recycling through endocytosis and its role in nutrient uptake and maintaining cellular homeostasis.

  • Types of Endocytosis: Compare and contrast pinocytosis, receptor-mediated endocytosis, and phagocytosis, highlighting their mechanisms and physiological roles.

Description of Vesicular Transport

Basics of Vesicles

  • Vesicles are membrane-bound sacs that serve as transport vehicles within cells, facilitating the movement of proteins, lipids, and other biomolecules between different cellular compartments such as the endoplasmic reticulum (ER), Golgi apparatus, and plasma membrane.

  • They originate from coated regions of donor compartments, shedding their coats to become capable of fusing with recipient membranes, thereby delivering their cargo.

  • Important Figures: Refer to