Showing papers on "Bromodomain published in 1997"

MLL is fused to CBP, a histone acetyltransferase, in therapy-related acute myeloid leukemia with a t(11;16)(q23;p13.3)

Abstract: The recurring translocation t(11;16)(q23;p13.3) has been documented only in cases of acute leukemia or myelodysplasia secondary to therapy with drugs targeting DNA topoisomerase II. We show that the MLL gene is fused to the gene that codes for CBP (CREB-binding protein), the protein that binds specifically to the DNA-binding protein CREB (cAMP response element-binding protein) in this translocation. MLL is fused in-frame to a different exon of CBP in two patients producing chimeric proteins containing the AT-hooks, methyltransferase homology domain, and transcriptional repression domain of MLL fused to the CREB binding domain or to the bromodomain of CBP. Both fusion products retain the histone acetyltransferase domain of CBP and may lead to leukemia by promoting histone acetylation of genomic regions targeted by the MLL AT-hooks, leading to transcriptional deregulation via aberrant chromatin organization. CBP is the first partner gene of MLL containing well defined structural and functional motifs that provide unique insights into the potential mechanisms by which these translocations contribute to leukemogenesis.

Histone acetyltransferase activity and interaction with ADA2 are critical for GCN5 function in vivo.

Abstract: Yeast GCN5 is one component of a putative adaptor complex that includes ADA2 and ADA3 and functionally connects DNA‐bound transcriptional activators with general transcription factors. GCN5 possesses histone acetyltransferase (HAT) activity, conceptually linking transcriptional activation with enzymatic modification at chromatin. We have identified the minimal catalytic domain within GCN5 necessary to confer HAT activity and have shown that in vivo activity of GCN5 requires this domain. However, complementation of growth and transcriptional activation in gcn5 − cells required not only the HAT domain of GCN5, but also interaction with ADA2. The bromodomain in GCN5 was dispensable for HAT activity and for transcriptional activation by strong activators; however, it was required for full complementation in other assays. Fusion of GCN5 to the bacterial lexA DNA binding domain activated transcription in vivo , and required both the HAT domain and the ADA2 interaction domain. These results suggest that both functions of GCN5, HAT activity and interaction with ADA2, are necessary for targeting and acetylation of nucleosomal histones.

Nucleotide sequences that encode phosphatidylinositol-3' kinase associated proteins and uses thereof

Abstract: Identification, characterization and expression of nucleotides that encode phosphatidylinositol-3' kinase associated protein(s) that bind to the intermediate SH2 domain on the regulatory subunit of PI3K, p85, by the associated protein(s) C-terminal amino acids, and that exhibit a bromodomain are described, as well as methods of using such proteins for medical applications, including diagnosis and treatment cell growth disorders.