Set2 co-transcriptionally methylates lysine 36 of histone H3 (H3K36), producing mono-, di-, and trimethylation (H3K36me1/2/3). These modifications recruit or repel chromatin effector proteins important for transcriptional fidelity, mRNA splicing, and DNA repair. However, it was not known whether the different methylation states of H3K36 have distinct biological functions.
View Article and Find Full Text PDFH2A.Z is a histone H2A variant that contributes to transcriptional regulation, DNA damage response and limits heterochromatin spreading. In Saccharomyces cerevisiae, H2A.
View Article and Find Full Text PDFThe yeast Set2 histone methyltransferase is a critical enzyme that plays a number of key roles in gene transcription and DNA repair. Recently, the human homologue, SETD2, was found to be recurrently mutated in a significant percentage of renal cell carcinomas, raising the possibility that the activity of SETD2 is tumor-suppressive. Using budding yeast and human cell line model systems, we examined the functional significance of two evolutionarily conserved residues in SETD2 that are recurrently mutated in human cancers.
View Article and Find Full Text PDFThe plant homeodomain (PHD) finger is found in many chromatin-associated proteins and functions to recruit effector proteins to chromatin through its ability to bind both methylated and unmethylated histone residues. Here, we show that the dual PHD fingers of Rco1, a member of the Rpd3S histone deacetylase complex recruited to transcribing genes, operate in a combinatorial manner in targeting the Rpd3S complex to histone H3 in chromatin. Although mutations in either the first or second PHD finger allow for Rpd3S complex formation, the assembled complexes from these mutants cannot recognize nucleosomes or function to maintain chromatin structure and prevent cryptic transcriptional initiation from within transcribed regions.
View Article and Find Full Text PDFThe YEATS domain, found in a number of chromatin-associated proteins, has recently been shown to have the capacity to bind histone lysine acetylation. Here, we show that the YEATS domain of Taf14, a member of key transcriptional and chromatin-modifying complexes in yeast, is a selective reader of histone H3 Lys9 acetylation (H3K9ac). Structural analysis reveals that acetylated Lys9 is sandwiched in an aromatic cage formed by F62 and W81.
View Article and Find Full Text PDFThe importance of understanding the molecular mechanisms of murine leukemia virus (MLV) integration into host chromatin is highlighted by the development of MLV-based vectors for human gene-therapy. We have recently identified BET proteins (Brd2, 3 and 4) as the main cellular binding partners of MLV integrase (IN) and demonstrated their significance for effective MLV integration at transcription start sites. Here we show that recombinant Brd4, a representative of the three BET proteins, establishes complementary high-affinity interactions with MLV IN and mononucleosomes (MNs).
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