Although the details of the structural involvement of histone H1 in the organization of the nucleosome are quite well understood, the sequential events involved in the recognition of its binding site are not as well known. We have used a recombinant human histone H1 (H1.1) in which the N- and C-terminal domains (NTD/CTD) have been swapped and we have reconstituted it on to a 208-bp nucleosome. We have shown that the swapped version of the protein is still able to bind to nucleosomes through its structurally folded wing helix domain (WHD); however, analytical ultracentrifuge analysis demonstrates its ability to properly fold the chromatin fibre is impaired. Furthermore, FRAP analysis shows that the highly dynamic binding association of histone H1 with the chromatin fibre is altered, with a severely decreased half time of residence. All of this suggests that proper binding of histone H1 to chromatin is determined by the simultaneous and synergistic binding of its WHD-CTD to the nucleosome.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613717 | PMC |
http://dx.doi.org/10.1042/BSR20150087 | DOI Listing |
Biochemistry
January 2025
Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States.
is the leading cause of food poisoning in Europe and North America. The exterior surface of this bacterium is encased by a capsular polysaccharide that is attached to a diacyl glycerol phosphate anchor via a poly-Kdo (3-deoxy-d--oct-2-ulosinic acid) linker. In the HS:2 serotype of NCTC 11168, the repeating trisaccharide consists of d-ribose, -acetyl-d-glucosamine, and d-glucuronate.
View Article and Find Full Text PDFPLoS Pathog
January 2025
Institute of Pediatric Infection, Immunity, and Critical Care Medicine, Shanghai Children's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Function-to-find domain (FIIND)-containing proteins, including NLRP1 and CARD8, are vital components of the inflammasome signaling pathway, critical for the innate immune response. These proteins exist in various forms due to autoproteolysis within the FIIND domain, resulting in full-length (FL), cleaved N-terminal (NT), and cleaved C-terminal (CT) peptides, which form autoinhibitory complexes in the steady state. However, the detailed mechanism remains elusive.
View Article and Find Full Text PDFMicrob Genom
January 2025
Department of Pediatrics, Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Emory University School of Medicine, Atlanta, Georgia, USA.
Bacteria from the complex (Smc) are important multidrug-resistant pathogens that cause a broad range of infections. Smc is genomically diverse and has been classified into 23 lineages. Lineage Sm6 is the most common among sequenced strains, but it is unclear why this lineage has evolved to be dominant.
View Article and Find Full Text PDFmBio
January 2025
Department of Pediatrics, Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
Unlabelled: Interlinked interactions between the viral capsid (CA), nucleoporins (Nups), and the antiviral protein myxovirus resistance 2 (MX2/MXB) influence human immunodeficiency virus 1 (HIV-1) nuclear entry and the outcome of infection. Although RANBP2/NUP358 has been repeatedly identified as a critical player in HIV-1 nuclear import and MX2 activity, the mechanism by which RANBP2 facilitates HIV-1 infection is not well understood. To explore the interactions between MX2, the viral CA, and RANBP2, we utilized CRISPR-Cas9 to generate cell lines expressing RANBP2 from its endogenous locus but lacking the C-terminal cyclophilin (Cyp) homology domain and found that both HIV-1 and HIV-2 infections were reduced significantly in RANBP2 cells.
View Article and Find Full Text PDFCells
January 2025
Department of Ophthalmology & Visual Sciences, The University of Michigan, Ann Arbor, MI 48109, USA.
Heat shock proteins (HSPs) are essential molecular chaperones that protect cells by aiding in protein folding and preventing aggregation under stress conditions. Small heat shock proteins (sHSPs), which include members from HSPB1 to HSPB10, are particularly important for cellular stress responses. These proteins share a conserved α-crystallin domain (ACD) critical for their chaperone function, with flexible N- and C-terminal extensions that facilitate oligomer formation.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!