Related Experiment Video
Updated: Mar 14, 2026
08:26
Semi-quantitative Detection of RNA-dependent RNA Polymerase Activity of Human Telomerase Reverse Transcriptase Protein
Published on: June 12, 2018
10.5K
Human Telomerase Reverse Transcriptase (hTERT) Positively Regulates 26S Proteasome Activity
Eunju Im1, Jong Bok Yoon2, Han-Woong Lee2
1Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, Korea.
Journal of Cellular Physiology
|September 21, 2016
Summary
Human telomerase reverse transcriptase (hTERT) acts as a chaperone, promoting 26S proteasome assembly and activity. This non-telomeric function protects acute myeloid leukemia cells from ER stress.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Human telomerase reverse transcriptase (hTERT) is the catalytic subunit of telomerase.
- hTERT has known non-telomeric functions in tumor progression and neuronal cell death.
- The 26S proteasome complex is crucial for ubiquitin-dependent proteolysis.
Purpose of the Study:
- To investigate the non-telomeric functions of hTERT.
- To determine hTERT's role in proteasome regulation.
- To assess hTERT's effect on cellular stress responses.
Main Methods:
- Co-immunoprecipitation to identify protein interactions.
- Assays to measure proteasome activity.
- Cellular models of ER stress in acute myeloid leukemia cells.
Main Results:
- hTERT interacts with 19S and 20S proteasome subunits.
- hTERT enhances 26S proteasome activity independently of its enzymatic function.
- hTERT confers cytoprotection against ER stress by activating the 26S proteasome.
Conclusions:
- hTERT functions as a novel chaperone for 26S proteasome assembly and maintenance.
- hTERT's interaction with the proteasome is a key non-telomeric function.
- hTERT activation of the proteasome offers a potential therapeutic target for ER stress in cancer.
Related Concept Videos
02:41Telomeres and Telomerase
28.2K
In eukaryotic DNA replication, a single-stranded DNA fragment remains at the end of a chromosome after the removal of the final primer. This section of DNA cannot be replicated in the same manner as the rest of the strand because there is no 3’ end to which the newly synthesized DNA can attach. This non-replicated fragment results in gradual loss of the chromosomal DNA during each cell duplication. Additionally, it can induce a DNA damage response by enzymes that recognize single-stranded...
28.2K
02:41Telomeres and Telomerase
7.8K
7.8K
02:15Replicative Cell Senescence
4.6K
Replicative cell senescence is a property of cells that allows them to divide a finite number of times throughout the organism's lifespan while preventing excessive proliferation. Replicative senescence is associated with the gradual loss of the telomere — short, repetitive DNA sequences found at the end of the chromosomes. Telomeres are bound by a group of proteins to form a protective cap on the ends of chromosomes. Embryonic stem cells express telomerase — an enzyme that adds...
4.6K
01:17The Proteasome Structure
2.0K
The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...
The proteasome is an...
2.0K
02:18The Proteasome
10.4K
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
10.4K
01:13The Proteasome
1.9K
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
1.9K