Related Experiment Video
Updated: Jul 24, 2025
06:48
Author Spotlight: Evaluation of Protein-Condensate Dynamics in Live Human Cells
Published on: January 5, 2024
3.8K
Interplay between charge distribution and DNA in shaping HP1 paralog phase separation and localization
Tien M Phan1, Young C Kim2, Galia T Debelouchina3
1Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA.
Biorxiv : the Preprint Server for Biology
|July 3, 2023
Summary
The study reveals that the net charge and charge patterns in protein sequences dictate how heterochromatin protein 1 (HP1) paralogs interact. DNA binding also influences HP1 paralog interactions and condensate stability.
Area of Science:
- Molecular Biology
- Biophysics
- Computational Biology
Background:
- The heterochromatin protein 1 (HP1) family is essential for heterochromatin formation and function.
- Human cells possess three HP1 paralogs (HP1α, HP1β, HP1γ) with similar structures but distinct liquid-liquid phase separation (LLPS) behaviors.
Conclusions:
- Physicochemical properties of HP1 paralog sequences drive their distinct phase separation behaviors.
- Understanding these interactions provides a molecular basis for HP1's role in chromatin organization.
- DNA acts as a significant modulator of HP1-mediated chromatin condensates.
Related Concept Videos
02:32Position-effect Variegation
6.4K
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
6.4K
01:32Chromatin Packaging
16.8K
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...
16.8K
02:54Nucleosome Remodeling
9.2K
Nucleosomes are the basic units of chromatin compaction. Each nucleosome consists of the DNA bound tightly around a histone core, which makes the DNA inaccessible to DNA binding proteins such as DNA polymerase and RNA polymerase. Hence, the fundamental problem is to ensure access to DNA when appropriate, despite the compact and protective chromatin structure.
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
9.2K
02:05Duplication of Chromatin Structure
5.6K
The process of chromosome duplication during cell division requires genome-wide disruption and re-assembly of chromatin. The chromatin structure must be accurately inherited, reassembled, and maintained in the daughter cells to ensure lineage propagation.
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
5.6K
02:31Chromosome Replication
8.8K
Before a cell can divide, it must accurately replicate all of its chromosomes, including the DNA and its associated histone and non-histone proteins. This process begins at numerous origins of replication during the S phase of the cell cycle in each of a cell’s chromosomes simultaneously. Certain nucleotides can act as origins of replication, but these sequences are not well defined - especially in complex, multi-cellular, eukaryotic species. The length of DNA that spans an origin...
8.8K
03:17Inheritance of Chromatin Structures
6.3K
Epigenetics is the study of inherited changes in a cell's phenotype without changing the DNA sequences. It provides a form of memory for the differential gene expression pattern to maintain cell lineage, position-effect variegation, dosage compensation, and maintenance of chromatin structures such as telomeres and centromeres. For example, the structure and location of the centromere on chromosomes are epigenetically inherited. Its functionality is not dictated or ensured by the underlying...
6.3K