TY - JOUR AU - Ukmar-Godec, Tina AU - Yu, Taekyung AU - Ibanez de Opakua, Alain AU - Pantoja, Christian F AU - Munari, Francesca AU - Zweckstetter, Markus TI - Conformational diversity of human HP1α. JO - Protein science VL - 33 IS - 7 SN - 0961-8368 CY - Bethesda, Md. PB - Protein Society M1 - DZNE-2024-00793 SP - e5079 PY - 2024 AB - Heterochromatin protein 1 alpha (HP1α) is an evolutionarily conserved protein that binds chromatin and is important for gene silencing. The protein comprises 191 residues arranged into three disordered regions and two structured domains, the chromo and chromoshadow domain, which associates into a homodimer. While high-resolution structures of the isolated domains of HP1 proteins are known, the structural properties of full-length HP1α remain largely unknown. Using a combination of NMR spectroscopy and structure predictions by AlphaFold2 we provide evidence that the chromo and chromoshadow domain of HP1α engage in direct contacts resulting in a compact chromo/chromoshadow domain arrangement. We further show that HP1β and HP1γ have increased interdomain dynamics when compared to HP1α which may contribute to the distinct roles of different Hp1 isoforms in gene silencing and activation. KW - Chromobox Protein Homolog 5: chemistry KW - Chromosomal Proteins, Non-Histone: chemistry KW - Chromosomal Proteins, Non-Histone: genetics KW - Chromosomal Proteins, Non-Histone: metabolism KW - Humans KW - Models, Molecular KW - Nuclear Magnetic Resonance, Biomolecular KW - Protein Domains KW - Protein Conformation KW - HP1α (Other) KW - AlphaFold (Other) KW - HP1α (Other) KW - NMR spectroscopy (Other) KW - chromatin (Other) KW - dynamics (Other) KW - residual dipolar couplings (Other) KW - Chromobox Protein Homolog 5 (NLM Chemicals) KW - Chromosomal Proteins, Non-Histone (NLM Chemicals) KW - CBX5 protein, human (NLM Chemicals) LB - PUB:(DE-HGF)16 C6 - pmid:38895997 C2 - pmc:PMC11187854 DO - DOI:10.1002/pro.5079 UR - https://pub.dzne.de/record/270413 ER -