Search results for "Transferase"
showing 10 items of 1030 documents
Bromodomain factor 1 (Bdf1) protein interacts with histones
2001
AbstractUsing a yeast two-hybrid assay we detected an interaction between the N-terminal region of histone H4 (amino acids 1–59) and a fragment of the bromodomain factor 1 protein (Bdf1p) (amino acids 304–571) that includes one of the two bromodomains of this protein. No interaction was observed using fragments of histone H4 sequence smaller than the first 59 amino acids. Recombinant Bdf1p (rBdf1p) demonstrates binding affinity for histones H4 and H3 but not H2A and H2B in vitro. Moreover, rBdf1p is able to bind histones H3 and H4 having different degrees of acetylation. Finally, we have not detected histone acetyltransferase activity associated with Bdf1p.
The yeast histone acetyltransferase A2 complex, but not free Gcn5p, binds stably to nucleosomal arrays.
2000
We have investigated the structural basis for the differential catalytic function of the yeast Gcn5p-containing histone acetyltransferase (HAT) A2 complex and free recombinant yeast Gcn5p (rGcn5p). HAT A2 is shown to be a unique complex that contains Gcn5p, Ada2p, and Ada3p, but not proteins specific to other related HAT A complexes, e.g. ADA, SAGA. Nevertheless, HAT A2 produces the same unique polyacetylation pattern of nucleosomal substrates reported previously for ADA and SAGA, demonstrating that proteins specific to the ADA and SAGA complexes do not influence the enzymatic activity of Gcn5p within the HAT A2 complex. To investigate the role of substrate interactions in the differential …
AcetyltransferaseSAS2and sirtuinSIR2,respectively, control flocculation and biofilm formation in wine yeast
2014
Cell-to-cell and cell-to-environment interactions of microorganisms are of substantial relevance for their biotechnological use. In the yeast Saccharomyces cerevisiae, flocculation can be an advantage to clarify final liquid products after fermentation, and biofilm formation may be relevant for the encapsulation of strains of interest. The adhesion properties of wine yeast strains can be modified by the genetic manipulation of transcriptional regulatory proteins, such as histone deacetylases, and acetylases. Sirtuin SIR2 is essential for the formation of mat structures, a kind of biofilm that requires the expression of cell-wall protein FLO11 as its deletion reduces FLO11 expression, and ad…
A short-range gradient of histone H3 acetylation and Tup1p redistribution at the promoter of the Saccharomyces cerevisiae SUC2 gene.
2003
Chromatin immunoprecipitation assays are used to map H3 and H4 acetylation over the promoter nucleosomes and the coding region of the Saccharomyces cerevisiae SUC2 gene, under repressed and derepressed conditions, using wild type and mutant strains. In wild type cells, a high level of H3 acetylation at the distal end of the promoter drops sharply toward the proximal nucleosome that covers the TATA box, a gradient that become even steeper on derepression. In contrast, substantial H4 acetylation shows no such gradient and extends into the coding region. Overall levels of both H3 and H4 acetylation rise on derepression. Mutation of GCN5 or SNF2 lead to substantially reduced SUC2 expression; in…
Unveiling novel interactions of histone chaperone Asf1 linked to TREX-2 factors Sus1 and Thp1
2014
13 páginas, 7 figuras, 2 yablas
Yeast HAT1 and HAT2 deletions have different life-span and transcriptome phenotypes
2005
AbstractHAT-B is a yeast histone acetyltransferase composed of Hat1, Hat2 and Hif1 proteins. We demonstrate that a hat2 mutant or a hat1hat2 double mutant, but not a hat1 mutant, have an extended life-span. Transcriptome analysis shows that the single hat mutants are not very different from wild type. However, the comparison of the hat1 and hat2 transcriptomes shows that they are different. The hat1hat2 double mutant shows a transcriptional phenotype similar to that of the hat1 mutant but strongly enhanced. These results indicate that Hat2p could have additional functions in the cell to those of Hat1p.
A DNA region ofTorulaspora delbrueckii containing theHIS3 gene: sequence, gene order and evolution
2003
We cloned a genomic DNA fragment of the yeast Torulaspora delbrueckii by complementation of a Saccharomyces cerevisiae his3 mutant strain. DNA sequence analysis revealed that the fragment contained two complete ORFs, which share a high similarity with S. cerevisiae His3p and Mrp51p, respectively. The cloned TdHIS3 gene fully complemented the his3 mutation of S. cerevisiae, confirming that it encodes for the imidazoleglycerol-phosphate dehydrate of T. delbrueckii. Two additional ORFs, with a high homology to S. cerevisiae PET56 and DED1 genes, were mapped upstream and downstream from TdHIS3 and TdMRP51, respectively. This genetic organization is analogous to that previously found in Saccharo…
Urmylation and tRNA thiolation functions of ubiquitin-like Uba4·Urm1 systems are conserved from yeast to man
2015
AbstractThe ubiquitin-like protein Urm1 from budding yeast and its E1-like activator Uba4 have dual roles in protein urmylation and tRNA thiolation pathways. To study whether these are conserved among eukaryotes, we used gene shuffles to replace the yeast proteins by their human counterparts, hURM1 and hUBA4/MOCS3. As judged from biochemical and genetical assays, hURM1 and hUBA4 are functional in yeast, albeit at reduced efficiencies. They mediate urmylation of the peroxiredoxin Ahp1, a known urmylation target in yeast, and support tRNA thiolation. Similar to hUBA4, yeast Uba4 itself is modified by Urm1 and hURM1 suggesting target overlap between eukaryal urmylation pathways. In sum, our st…
Hif1 Is a Component of Yeast Histone Acetyltransferase B, a Complex Mainly Localized in the Nucleus
2004
Hat1 is the catalytic subunit of the only type B histone acetyltransferase known (HAT-B). The enzyme specifically acetylates lysine 12, and to a lesser extent lysine 5, of free, non-chromatin-bound histone H4. The complex is usually isolated with cytosolic fractions and is thought to be involved in chromatin assembly. The Saccharomyces cerevisiae HAT-B complex also contains Hat2, a protein stimulating Hat1 catalytic activity. We have now identified by two-hybrid experiments Hif1 as both a Hat1- and a histone H4-interacting protein. These interactions were dependent on HAT2, indicating a mediating role for Hat2. Biochemical fractionation and co-immunoprecipitation assays demonstrated that Hi…
Expression of the gene encoding secretor type galactoside 2 ? fucosyltransferase (FUT2) and ABH antigens in patients with oral lesions
2010
Objective: The aim of this work was to evaluate the expression of FUT2 gene in saliva and histo ABH antigens of patients with oral lesions. Study Design: In total 178 subjects were examined, half of whom suffered from oral pre-cancerous and cancerous lesions, while the other half were the healthy control group We analyzed the FUT 2 polymorphism by ASO-PCR (allele specific oligonucleotid – polymerase chain reaction) with specific primers for G428 allele and the wild type allele of FUT2 gene. To reveal A, B and H antigens in tissue sections of the patients (n= 89) we used a modified specific red cell adherence technique. Results: We found a high intensity of oral disease in the non-secretor g…