Related Experiment Video
Updated: Jul 10, 2026

Quantifying Spatiotemporal Parameters of Cellular Exocytosis in Micropatterned Cells
Published on: September 16, 2020
Mechanisms of exocytosis
1Division of Fundamental Neurobiology, Toronto Western Research Institute, University Health Network and Department of Physiology, University of Toronto, Toronto, ON, Canada. ssugita@uhnres.utoronto.ca
Abstract:
Catecholamines and peptides secreted from dense-core vesicles (DCVs) of adrenal chromaffin cells regulate a wide variety of physiological processes. For instance, the release of noradrenaline and adrenaline plays a key role in regulating heart rate and blood pressure. Thus understanding the mechanisms of secretory processes of DCVs is crucial for understanding the basis of diseases such as hypertension. DCVs undergo several stages of secretory processing before they are exocytosed. These include docking, priming and triggering of membrane fusion/exocytosis. Molecular studies of DCV exocytosis have identified many proteins critically involved in DCV secretion. These proteins include SNARE proteins, Munc18-1, phosphatidylinositol transfer protein, type I phosphatidylinositol-4-phosphate-5-kinases, NSF, Munc13, CAPS1, synaptotagmins, RalA/RalB GTPases and exocyst proteins. In this article, I will discuss the functions of these proteins within the context of the stages (i.e. docking, priming and triggering of membrane fusion/exocytosis) in DCV secretion.
Related Concept Videos
Exocytosis
Exocytosis is the opposite of endocytosis, which brings molecules inside the cell. Sometimes, the released materials are signaling molecules. For example, neurons typically use exocytosis to release neurotransmitters. Cells also use exocytosis to insert proteins such as ion channels into their cell membranes, secrete proteins for use in the extracellular matrix, or...
Exocytosis
Vesicular Trasport: Endocytosis, Transcytosis and Exocytosis
Endocytosis is a cellular mechanism that involves the inward folding of the cell membrane to create vesicles that capture and transport large drug molecules. This process comprises two distinct methods: pinocytosis (often referred to as "cell drinking") and phagocytosis (often referred to as "cell eating"). Pinocytosis is...
Fusion of Secretory Vesicles with the Plasma Membrane
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
Introduction to Membrane Traffic
The transport of soluble and membrane proteins is mediated by transport vesicles that collect cargo from one cellular compartment and deliver it to another by fusing with the target organelle membrane. The Rab...
Overview of Secretory Vesicles
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...

