Human HDAC1 and HDAC2 function in the DNA-damage response to promote DNA nonhomologous end-joining.

DNA double-strand break (DSB) repair occurs within chromatin and can be modulated by chromatin-modifying enzymes. Here we identify the related human histone deacetylases HDAC1 and HDAC2 as two participants in the DNA-damage response. We show that acetylation of histone H3 Lys56 (H3K56) was regulated by HDAC1 and HDAC2 and that HDAC1 and HDAC2 were rapidly recruited to DNA-damage sites to promote hypoacetylation of H3K56.

CDK2AP1/DOC-1 is a bona fide subunit of the Mi-2/NuRD complex.

The Mi-2/NuRD (NUcleosome Remodeling and histone Deacetylase) chromatin remodeling complex is a large heterogeneous multiprotein complex associated with transcriptional repression. Here we apply a SILAC based quantitative proteomics approach to show that all known Mi-2/NuRD complex subunits co-purify with Cyclin Dependent Kinase 2 Associated Protein1 (CDK2AP1), also known as Deleted in Oral Cancer 1 (DOC-1). DOC-1 displays in vitro binding affinity for methylated DNA as part of the meCpG binding MBD2/NuRD complex.

Screen for DNA-damage-responsive histone modifications identifies H3K9Ac and H3K56Ac in human cells.

Recognition and repair of damaged DNA occurs within the context of chromatin. The key protein components of chromatin are histones, whose post-translational modifications control diverse chromatin functions. Here, we report our findings from a large-scale screen for DNA-damage-responsive histone modifications in human cells.

Coiled-coil interactions modulate multimerization, mitochondrial binding and kinase activity of myotonic dystrophy protein kinase splice isoforms.

The myotonic dystrophy protein kinase polypeptide repertoire in mice and humans consists of six different splice isoforms that vary in the nature of their C-terminal tails and in the presence or absence of an internal Val-Ser-Gly-Gly-Gly motif. Here, we demonstrate that myotonic dystrophy protein kinase isoforms exist in high-molecular-weight complexes controlled by homo- and heteromultimerization. This multimerization is mediated by coiled-coil interactions in the tail-proximal domain and occurs independently of alternatively spliced protein segments or myotonic dystrophy protein kinase activity.