9osc | pdb_00009osc
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Crystal structure of HP1gamma chromoshadow domain in complex with KAP1 peptide
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Structural highlights
Publication Abstract from PubMedHP1s are involved in the assembly of heterochromatin and transcriptional regulation. Here, we report the molecular mechanisms underlying binding of the chromoshadow domain of HP1gamma (HP1gamma(CSD)) to the transcriptional co-repressor KAP1 and HP1gamma self-assembly. Using crystallography, NMR, and mass photometry, we show that HP1gamma(CSD) recognizes the HP1 box of KAP1 (KAP1(Hbox)) and forms a relatively stable dimer of dimers, assembled in an antiparallel manner, in contrast to the corresponding HP1alpha(CSD) complex, which shows concentration-dependent oligomerization and arrangement of HP1alpha(CSD) protomers in a parallel manner. The beta-sheet interface between HP1gamma(CSD) dimers is stabilized through electrostatic interactions, unlike the hydrophobic beta-sheet interface of HP1alpha(CSD). In vivo rescue experiments using KAP1- and HP1-knockout mouse embryonic stem cells reveal a unique cooperative action of KAP1 and HP1gamma, but not other HP1s, in the repression of the long noncoding RNA AI662270, underscoring the notion that cellular functions of HP1 proteins are not redundant. HP1gamma self-assembles and cooperates with KAP1 in repression of long noncoding RNA AI662270 in ESCs.,Gaurav N, Qin W, Selvam K, Zhou Z, Liu J, Yin Y, Singh RK, O'Hara RA, Tavaf Z, Kumar A, Kono H, Narlikar GJ, Banaszynski LA, Leonhardt H, Kutateladze TG Cell Rep. 2026 Jan 21;45(2):116874. doi: 10.1016/j.celrep.2025.116874. PMID:41575850[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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This page was last modified 19:26, 10 February 2026.