Down Regulation
Down Regulation - Related Videos
01:15
Receptor Downregulation in MVBs
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2023
Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded. The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR activation may...
10:16
SorLA and CLC:CLF-1-dependent Downregulation of CNTFRα as Demonstrated by Western Blotting, Inhibition of Lysosomal Enzymes, and Immunocytochemistry
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Cited by 1 •
2017
The present protocol describes how Western blotting and immunocytochemistry combined with inhibition of lysosomal enzymes can be used to demonstrate the downregulation of Ciliary Neurotrophic Factor Receptor-α (CNTFRα), which is conveyed by the interaction between Cytokine-like Factor-1 (CLF-1) and the endocytic receptor sorLA.
05:24
In Vivo SiRNA Transfection and Gene Knockdown in Spinal Cord via Rapid Noninvasive Lumbar Intrathecal Injections in Mice
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Cited by 57 •
2014
This report describes a simple and rapid technique of intrathecal needle puncture for a localized transfection of siRNA in the lumbar spinal cord in mouse under short lasting light anesthesia.
07:56
Bacterial Delivery of RNAi Effectors: Transkingdom RNAi
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Cited by 18 •
2010
For development of RNA interference (RNAi)-based therapies, a novel strategy was developed, transkingdom RNAi (tkRNAi). This technology uses non-pathogenic bacteria to produce and deliver therapeutic short hairpin RNA (shRNA) into target cells. Here, tkRNAi was successfully applied for reversal of classical ABCB1-mediated multidrug resistance (MDR) of cancer cells.
02:59
Cell Fate Reprogramming of Nematode Germ Cells into Neurons
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2025
This video demonstrates cell fate reprogramming of nematode germ cells into neurons. Transgenic larvae of the nematode Caenorhabditis elegans are subjected to RNA interference (RNAi) to knock down a specific chromatin-regulating factor, making the germ cells of their progeny more susceptible to cell fate reprogramming. Heat shock is applied to the progeny, inducing the germ cells to express a neuron-specific transcription factor that triggers their transformation into neurons, which is...
FAQs
Prolonged stimulation can trigger down regulation through several control points rather than a single cellular switch. Cells may repress transcription, reduce protein synthesis, internalize receptors, degrade existing molecules, or activate feedback that lowers pathway activity. These alternatives help explain why a later response may weaken even when the original hormone, neurotransmitter, growth factor, or environmental cue remains present.
Down regulation can change abundance, activity, or responsiveness, and those outcomes are not interchangeable. Transcriptional repression and reduced protein synthesis primarily limit how much of a molecule is produced, whereas receptor internalization or degradation can reduce signaling capacity. A change in pathway activity may also reflect feedback, so interpretation requires identifying which control point has changed.
Feedback mechanisms make down regulation important for homeostasis because they restrain signaling after stimulation has become prolonged or excessive. By lowering pathway activity, the cell can prevent an ongoing cue from producing an unlimited response. This principle applies across signaling systems, including those controlled by hormones, neurotransmitters, growth factors, and environmental signals.
Receptor internalization matters because it can reduce a cell's ability to respond without requiring immediate removal of the external signal. In this form of regulation, receptors are taken out of the cell surface, while degradation can remove molecules through another control route. Distinguishing these mechanisms connects reduced responsiveness with the cellular event producing it.
An investigation can focus on the level at which signaling changes. Researchers may examine transcriptional repression, protein synthesis, receptor internalization, degradation, feedback, and overall pathway activity. Considering these features together helps determine whether reduced signaling reflects a lower amount of a molecule, diminished molecular activity, or reduced cellular responsiveness after prolonged stimulation.
Down regulation is relevant to signaling systems controlled by hormones, neurotransmitters, growth factors, and environmental cues. These contexts allow researchers to examine how cells adapt when stimulation persists or changes over time. Comparing such systems can clarify how different biological signals are restrained while preserving cellular homeostasis and limiting excessive responses.
Drug tolerance research can use down regulation to examine why cellular responses may decrease during continued stimulation. Reduced receptor availability, altered molecular production, diminished activity, or feedback could each represent a different regulatory point to investigate. This framework helps connect persistent signaling with changes in responsiveness, without assuming that every tolerance-related response has the same cellular cause.
In endocrine signaling and immune regulation, down regulation helps explain how cells limit responses to continuing biological cues. Studying these controls can clarify how signaling is restrained during normal regulation and how abnormal cell communication may contribute to disease. The same framework therefore links basic cellular homeostasis with research into endocrine, immune, and communication-related disorders.