Regulated Secretion
Regulated Secretion - Related Videos
01:19
Regulation of Hormone Secretion
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2024
Regulation of hormone secretion is a finely tuned orchestration driven by various types of stimuli, encompassing neural, humoral, and hormonal signals. Environmental cues instigate neural stimuli, where action potentials traverse nerve fibers to reach their designated targets. An illustrative scenario is the body's response to stress, wherein the sympathetic nervous system releases epinephrine from the adrenal glands, inducing the well-known 'fight or flight' reaction. Humoral stimuli,...
02:22
Regulated mRNA Transport
0 Views •
2020
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...
03:51
Label-Free Neutrophil Separation from Tracheal Secretion Using Spiral Microfluidics Channel
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2025
This video demonstrates separating neutrophils from tracheal secretions using a microfluidic device with spiral channels. The device achieves efficient separation based on cell size by utilizing varying thicknesses and trapezoidal-shaped channels. The interplay between forces results in large neutrophils accumulating near the inner wall while erythrocytes and mucin aggregates remain near the outer wall, ensuring effective neutrophil separation.
02:14
GTPases and their Regulation
0 Views •
2020
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins. Large G-proteins, also known...
05:58
Measuring Relative Insulin Secretion using a Co-Secreted Luciferase Surrogate
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Cited by 7 •
2019
This protocol describes how to perform rapid low-cost luciferase assays at medium-throughput using an insulin-linked Gaussia luciferase as a proxy for insulin secretion from beta cells. The assay can be performed with most luminescence plate readers and multichannel pipettes.
FAQs
Calcium entry provides the stimulus that converts a prepared secretory vesicle into a releasing vesicle. Cargo has already accumulated, and the vesicle has docked at the plasma membrane before the signal arrives. Calcium then activates the fusion process, allowing exocytosis to occur at the appropriate moment rather than continuously.
Docking positions a cargo-filled vesicle at the plasma membrane, placing it where fusion can occur rapidly after stimulation. This arrangement separates preparation from release: the cell can accumulate its product and keep it ready, then respond efficiently when an external signal causes calcium entry. Docking therefore supports precise timing and controlled output.
The process links an external signal to the selective release of stored cellular products. Neurons can communicate by releasing neurotransmitters, endocrine cells can deliver hormones, and digestive cells can provide enzymes when required. Because release follows stimulation instead of occurring continuously, cells coordinate communication and metabolic activities with the needs of surrounding tissues.
Several specialized cell types use this mechanism for different biological tasks. Neurons release neurotransmitters to support signaling, endocrine cells secrete hormones that coordinate body functions, and digestive cells release enzymes involved in digestion. The shared secretory strategy produces different outcomes because the stored cargo and the receiving tissue differ among cell types.
A useful sequence begins with cargo accumulation inside secretory vesicles, followed by vesicle docking at the plasma membrane. Researchers then consider the external stimulus, calcium entry, activation of vesicle fusion, and exocytosis. Tracking these linked stages helps relate storage and preparation to the final release of a signaling molecule or other cellular product.
Defects in this process can disrupt the controlled delivery of neurotransmitters, hormones, or digestive enzymes. Such failures may affect cellular communication, endocrine function, or digestion and are associated with neurological, endocrine, and immune disorders. Examining where the sequence fails, from vesicle preparation through calcium-triggered fusion, can connect cellular mechanisms with tissue-level dysfunction.