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.
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http://dx.doi.org/10.1038/nchembio.501 | DOI Listing |
Nucleic Acids Res
January 2025
Institute of Reproductive Medicine, School of Medicine, Nantong University, Nantong 226001, China.
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 PDFAdv 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 PDFJ 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:
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:
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.
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