Related Experiment Video
Updated: Nov 9, 2025
11:21
Author Spotlight: Advanced Single-Molecule Techniques for Investigating Telomeric Protein-DNA Interactions
Published on: August 30, 2024
969
Dynamic DNA Shortening by Telomere-Binding Protein Cdc13
Yi-Yun Lin1, Min-Hsuan Li1, Yen-Chan Chang2
1Institute of Biochemistry and Molecular Biology, National Taiwan University, Taipei City 10617, Taiwan.
Journal of the American Chemical Society
|April 8, 2021
Summary
Cdc13 protein binding to telomeric DNA shortens it, forming a stable complex that protects chromosome ends. This DNA shortening mechanism is crucial for telomere maintenance and protection.
Area of Science:
- Molecular Biology
- Genetics
- Biophysics
Background:
- Telomeres are vital for chromosome stability.
- Cdc13 protein caps telomeres and regulates telomerase in yeast.
- The precise mechanism of Cdc13-DNA complex in telomere protection remains unclear.
Purpose of the Study:
- To elucidate the mechanism by which Cdc13-DNA complexes protect telomeres.
- To investigate the structural changes induced by Cdc13 binding to telomeric DNA.
Main Methods:
- Single-molecule tethered particle motion (TPM).
- Atomic force microscopy (AFM).
Main Results:
- Specific binding of Cdc13 to single-stranded telomeric DNA induces shortening of duplex DNA.
- DNA shortening results in distinct states differing by approximately 70-80 base pairs.
- Cdc13-induced DNA shortening is dynamic and sequence-independent.
- Pif1 helicase cannot displace Cdc13 from the shortened DNA-Cdc13 complex, indicating structural stability.
Conclusions:
- Cdc13 binding shortens telomeric DNA, forming a structurally stable complex.
- This DNA shortening by Cdc13 is a key factor in efficient telomere end protection.
Related Concept Videos
02:41Telomeres and Telomerase
25.5K
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...
25.5K
02:41Telomeres and Telomerase
6.3K
6.3K
01:29Replication in Eukaryotes
15.8K
In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high fidelity before cell division, so there are many proteins that fulfill specialized roles in the replication process. Replication occurs in three phases: initiation, elongation, and termination, and ends with two complete sets of chromosomes in the nucleus.
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
15.8K
02:31Replication in Eukaryotes
185.0K
Overview
185.0K
02:15Replicative Cell Senescence
4.0K
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...
4.0K
01:32Chromatin Packaging
18.2K
Each human somatic cell contains 6 billion base pairs of DNA. Each base pair is 0.34 nm long, meaning each diploid cell contains a staggering 2 meters of DNA. This long DNA strand is packed inside a nucleus measuring only 10-20 microns in diameter with the help of specialized DNA-binding proteins called histones. Together they form a compact DNA-protein complex called chromatin. The chromatin is further compacted into higher-order structures. The highest level of compaction is achieved during...
18.2K