Fluorescence Microplate-Based Cycloheximide Chase Assay: A Technique to Monitor the Degradation Kinetics of Fluorescent Nuclear Misfolded Proteins

0 weergaven2:59 min • July 8th, 2025

Loading...
$$\rightleftharpoonup{xx}$$ $$\longleftharp{xx}$$, $$\longrightharp{xx}$$,

Nuclear misfolded proteins lacking a defined tertiary structure are tagged with small ubiquitin-like modifiers, SUMOs, and ubiquitin molecules, which facilitate their degradation by the proteolytic system, including the ubiquitin-proteasome system, the UPS.

In several neurodegenerative diseases, UPS dysfunction causes the accumulation and aggregation of nuclear misfolded proteins, leading to neuronal death.

To investigate the degradation rate of nuclear misfolded proteins in vitro, treat a culture of adherent mammalian cells with a mixture comprising a fluorescent-labeled misfolded protein-encoding plasmid DNA and a transfection reagent.

Successfully transfected cells express fluorescent-labeled, short half-life misfolded proteins tagged with a nuclear localization signal. Upon transportation to the nucleus, these misfolded proteins undergo SUMOylation and ubiquitination and are transferred to the UPS for protein degradation and clearance.

Post-incubation, replace the medium with a low-fluorescence medium containing cycloheximide. Cycloheximide, a cell-permeable molecule, binds to the large ribosomal unit and blocks the elongation phase of protein translation and further protein synthesis, facilitating the study of the degradation rate of the fluorescent-labeled translated misfolded proteins.

Treat a set of wells with a proteasome inhibitor to block the proteasome activity and cause the misfolded proteins to accumulate. Using a microplate reader, measure the fluorescence of the misfolded proteins.

A time-dependent decline in the fluorescence indicates misfolded protein degradation. Cells treated with the proteasome inhibitor exhibit similar fluorescence intensity over time, denoting the inhibition of misfolded protein degradation.

After seeding and transfecting HeLa cells in 96-well plates according to the text protocol; 20 to 24 hours after transfection, examine the cells for GFP expression. Remove the medium at approximately 200 microliters of 1x PBS to each well, and then, aspirate it to remove the residual DMEM.

Add 60 microliters of low-fluorescence DMEM with 5% FBS, and 50 micrograms per milliliter of cycloheximide, and add 10 micromolar MG132 to one set of samples.

With a fluorescence plate reader, measure the GFP signal reading the plates every hour for up to 8 to 10 hours. Export the data, and carry out statistical analysis according to the text protocol.

09:05

Cycloheximide Chase Analyse van de afbraak van eiwitten in Saccharomyces cerevisiae

Gerelateerde video's

0 Bekeken

08:59

Analyse van de vouwing van eiwitten, vervoer en afbraak in levende cellen door radioactieve Pulse Chase

Gerelateerde video's

0 Bekeken

09:25

Kwantificerende Subcellulaire Ubiquitin-proteasome activiteit in het knaagdier hersenen

Gerelateerde video's

0 Bekeken

10:27

Een fluorescentie microscopie Assay voor de bewaking Mitophagy in de Gist Saccharomyces cerevisiae

Gerelateerde video's

0 Bekeken

13:38

Monitoring Kinase en fosfatase activiteiten door middel van de celcyclus door Ratiometrische FRET

Gerelateerde video's

0 Bekeken

05:42

Misfolding-Prone Protein Degradation Assay: A Technique to Monitor Misfolded Protein Degradation Using Cycloheximide Treatment and Detergent Fractionation

Gerelateerde video's

0 Bekeken

13:52

Gekoppeld Testen voor Monitoring Protein Refolding in Saccharomyces cerevisiae

Gerelateerde video's

0 Bekeken

07:47

-Reporter gebaseerd Growth Assay voor systematische analyse van eiwitafbraak

Gerelateerde video's

0 Bekeken

10:56

Assays voor de afbraak van Misfolded Eiwitten in Cellen

Gerelateerde video's

0 Bekeken

12:06

Eencellige kwantificering van eiwit afbraak tarieven door Time-Lapse fluorescentie microscopie in aanhangend celkweek

Gerelateerde video's

0 Bekeken

Laatst bijgewerkt: 15 augustus 2026