Search results for "2A"
showing 10 items of 282 documents
p16INK4A (CDKN2A) gene deletion is a frequent genetic event in synovial sarcomas.
2006
We assessed the frequency of genomic deletion of p16 INK4A (CDKN2A) in synovial sarcomas (SSs) and its possible association with immunoexpression of p16 and cyclin D1 and the Ki-67 proliferation index using dualcolor fluorescence in situ hybridization (FISH) on tissue microarray sections of 41 histologically and molecularly confirmed SSs. A heterozygous p16 INK4A gene deletion was identified in 28 (74%) of 38 cases, with 25 (89%) of them showing abnormal p16 protein expression (20 negative and 5 heterogeneous). Of 25 cases, 19 (76%) exhibiting increased cyclin D1 expression also demonstrated heterozygous p16 INK4A deletion. No significant association was observed between p16 INK4A deletion …
Histone H3 Lysine 4 Mono-methylation does not Require Ubiquitination of Histone H2B
2005
The yeast Set1-complex catalyzes histone H3 lysine 4 (H3K4) methylation. Using N-terminal Edman sequencing, we determined that 50% of H3K4 is methylated and consists of roughly equal amounts of mono, di and tri-methylated H3K4. We further show that loss of either Paf1 of the Paf1 elongation complex, or ubiquitination of histone H2B, has only a modest effect on bulk histone mono-methylation at H3K4. Despite the fact that Set1 recruitment decreases in paf1delta cells, loss of Paf1 results in an increase of H3K4 mono-methylation at the 5' coding region of active genes, suggesting a Paf1-independent targeting of Set1. In contrast to Paf1 inactivation, deleting RTF1 affects H3K4 mono-methylation…
Naturally occurring testis-specific histone H3 antisense transcripts inDrosophila
1997
While analysing the transcription of the cluster of cell-cycle regulated histone genes in Drosophila hydei, we have found transcripts spanned both histone H3 and H4 genes and were antisense for histone H3. As the two histone genes are in opposite orientation, these transcripts contained the sense strand of the histone H4 gene. Such transcripts were present in both poly(A) + and poly(A) - RNA fractions. The polyadenylated molecules contained a poly(A) tail at the 3' end of the stem-loop structure, which is characteristic for cell-cycle regulated histone mRNAs. The antisense RNA of histone H3 is synthesized exclusively in testes. By developing an improved protocol of in situ hybridization to …
A chromatin-associated histone deacetylase from pea (Pisum sativum)
1991
Abstract A histone deacetylase activity has been found in preparation of chromatin from pea (Pisum sativum) embryonic axes. This activity readily deacetylates free histones and is somewhat specific for H2A and H2B; this property and its chromatographic behaviour allowed us to identify the enzyme with the previously described histone deacetylase HD2 (Sendra et al., Plant Mol. Biol., 11 (1988) 857). HD2 is only loosely associated to chromatin but the enzymatic activity is enhanced when chromatin adopts a folded conformation. Polyamines and divalent cations activate the enzyme, probably due to their effect on chromatin folding.
Distinct Site Specificity of Two Pea Histone Deacetylase Complexes
2001
We report on the site specificity of two intact pea histone deacetylase complexes. HD1 deacetylates lysines 5 and 16 of H4 in the order K16 > K5, while in the case of H3 the preferred order is K4 >> K18 approximately K9. The specificity of the HD2 complex is markedly different. The preferred residues in H4 are K8 approximately K5 > K16, while in H3 deacetylation, the complex HD2 prefers sites 4 and 18. To obtain these results, we have used a novel procedure based on the SPOT technique, a method to synthesize peptides on membrane supports. Different sets of membranes with sequentially overlapping histone peptides containing acetylated lysines in the sites corresponding to all in vivo acetyla…
Protein phosphatases and chromatin modifying complexes in the inflammatory cascade in acute pancreatitis
2010
Acute pancreatitis is an inflammation of the pancreas that may lead to systemic inflammatory response syndrome and death due to multiple organ failure. Acinar cells, together with leukocytes, trigger the inflammatory cascade in response to local damage of the pancreas. Amplification of the inflammatory cascade requires up-regulation of pro-inflammatory cytokines and this process is mediated not only by nuclear factor κB but also by chromatin modifying complexes and chromatin remodeling. Among the different families of histone acetyltransferases, the p300/CBP family seems to be particularly associated with the inflammatory process. cAMP activates gene expression via the cAMP-responsive eleme…
Identification of New Genetic Clusters in Glioblastoma Multiforme: EGFR Status and ADD3 Losses Influence Prognosis
2020
Glioblastoma multiforme (GB) is one of the most aggressive tumors. Despite continuous efforts to improve its clinical management, there is still no strategy to avoid a rapid and fatal outcome. EGFR amplification is the most characteristic alteration of these tumors. Although effective therapy against it has not yet been found in GB, it may be central to classifying patients. We investigated somatic-copy number alterations (SCNA) by multiplex ligation-dependent probe amplification in a series of 137 GB, together with the detection of EGFRvIII and FISH analysis for EGFR amplification. Publicly available data from 604 patients were used as a validation cohort. We found statistical associations…
Ink4/Arf locus restores glucose tolerance and insulin sensitivity by reducing hepatic steatosis and inflammation in mice with impaired IRS2-dependent…
2015
Single nucleotide polymorphisms near the Ink4/Arf locus have been associated with type-2 diabetes mellitus. Previous studies indicate a protective role of the locus in the carbohydrate metabolism derangement associated with ageing in wild-type mice. The present study demonstrates that the increased Ink4/Arf locus expression in 1-year-old mice, partially-deficient for the insulin receptor substrate (IRS)2 (Irs2 +/-SuperInk4/Arf mice) ameliorates hepatic steatosis, inflammation and insulin resistance. Irs2 +/-SuperInk4/Arf mice displayed improved glucose tolerance and insulin sensitivity compared with Irs2 +/- mice which were glucose intolerant and insulin resistant compared with age-matched …
Molecular mimicry may explain multi-organ damage in COVID-19
2020
International audience
Latvijas atradņu dzelzsrūdu sastāva noteikšana
2022
Latvijas atradņu dzelzsrūdu sastāva noteikšana. Vorobjovs D., zinātniskie vadītāji: prof., Dr. chem. Vīksna A. un asoc. prof., Dr. geol. Stinkulis Ģ. Bakalaura darbs, 62 lappuses, 35 attēli, 7 tabulas, 45 literatūrās avoti, 2 pielikumi. Latviešu valodā. Bakalaura darba ietvaros veica kvalitatīvo (mineraloģisko) dzelzsrūdu paraugu analīzi laboratorijas apstākļos, izmantojot pulvera rentgendifraktometrijas (XRD) metodi, ka arī tika izmantota rentgenstaru fluorescence (XRF) un lāzera inducētas sadalīšanās spektroskopija (LIBS) rūdu kvantitatīvā ķīmiskā sastāva noteikšanai.