Regulation of chromatin structure involves histone posttranslational modifications that can modulate intrinsic properties of the chromatin fiber to change the chromatin state. We used chemically defined nucleosome arrays to demonstrate that H2B ubiquitylation (uH2B), a modification associated with transcription, interferes with chromatin compaction and leads to an open and biochemically accessible fiber conformation. Notably, these effects were specific for ubiquitin, as compaction of chromatin modified with a similar ubiquitin-sized protein, Hub1, was only weakly affected. Applying a fluorescence-based method, we found that uH2B acts through a mechanism distinct from H4 tail acetylation, a modification known to disrupt chromatin folding. Finally, incorporation of both uH2B and acetylated H4 resulted in synergistic inhibition of higher-order chromatin structure formation, possibly a result of their distinct modes of action.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3078768PMC
http://dx.doi.org/10.1038/nchembio.501DOI Listing

Publication Analysis

Top Keywords

h2b ubiquitylation
8
chromatin
8
higher-order chromatin
8
chromatin compaction
8
chromatin structure
8
histone h2b
4
ubiquitylation disrupts
4
disrupts local
4
local higher-order
4
compaction regulation
4

Similar Publications

Chromatin remodeling, which involves the histone-to-protamine exchange process during spermiogenesis, is crucial for sperm nuclear condensation and male fertility. However, the key regulators and underlying molecular mechanisms involved in this process remain largely unexplored. In this study, we discovered that deficiency in the family with sequence similarity 170 member A (Fam170a) led to abnormal sperm nuclear morphology and male infertility in mice, mirroring the observation of very low Fam170a transcription levels in sperm of infertile men with teratozoospermia.

View Article and Find Full Text PDF

Unveiling the guardians of the genome: The dynamic role of histones in DNA organization and disease.

Adv Protein Chem Struct Biol

January 2025

CsrDD Lab, Department of Microbiology, Dr. D. Y. Patil Medical College Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth (Deemed to be University), Pimpri, Pune, India. Electronic address:

Histones are positively charged proteins found in the chromatin of eukaryotic cells. They regulate gene expression and are required for the organization and packaging of DNA within the nucleus. Histones are extremely conserved, allowing for transcription, replication, and repair.

View Article and Find Full Text PDF

Genome-wide profiling and functional study of short N-terminal H2B variants in Arabidopsis.

J Adv Res

December 2024

Department of Urology, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China; Hubei Hongshan Laboratory, Wuhan 430071, China. Electronic address:

Article Synopsis
  • - The study investigates the roles of specific histone H2B variants in the plant Arabidopsis thaliana, focusing on how these variants influence chromatin localization and gene regulation, which are key to understanding epigenetic mechanisms in plants.
  • - Four short N-terminal H2B variants (snH2Bs) were identified, and their genomic distribution, impact on plant growth, and regulatory functions were analyzed using advanced techniques like ChIP-seq combined with CRISPR-Cas9 gene editing.
  • - Results show that these snH2B variants are mainly expressed in reproductive tissues and play significant roles in gene expression and the transition from vegetative to reproductive stages in plants, highlighting their importance in chromatin regulation.
View Article and Find Full Text PDF

OsbZIP27 coordinates with OsHUB1 and OsHUB2 to modulate drought tolerance in rice.

J Genet Genomics

December 2024

Ministry of Education Key Laboratory for Membraneless Organelles and Cellular Dynamics, Hefei, Anhui 230027, China; School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China. Electronic address:

Article Synopsis
  • Histone H2B ubiquitination (H2Bub) is associated with enhanced transcription activities, particularly in regulating genetic programs for drought tolerance in rice.
  • The protein OsbZIP27 interacts with OsHUB1/2 to promote drought tolerance by binding to specific gene promoters, leading to increased H2Bub and gene expression.
  • Mutations in OsbZIP27 or loss of OsHUB1 and OsHUB2 function result in heightened drought sensitivity, while overexpressing OsHUB2 improves drought resistance.
View Article and Find Full Text PDF

An E2 ubiquitin-conjugating enzyme links diubiquitinated H2B to H3K27M oncohistone function.

Proc Natl Acad Sci U S A

November 2024

Ludwig Institute for Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom.

The H3K27M oncogenic histone (oncohistone) mutation drives ~80% of incurable childhood brain tumors known as diffuse midline gliomas (DMGs). The major molecular feature of H3K27M mutant DMGs is a global loss of H3K27 trimethylation (H3K27me3), a phenotype conserved in (). Here, we perform unbiased genome-wide suppressor screens in expressing H3K27M and isolate 20 suppressors, all of which at least partially restore H3K27me3.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!