Search results for "Multiprotein complex"
showing 10 items of 42 documents
Small molecule inhibitors of Apaf-1-related caspase- 3/-9 activation that control mitochondrial-dependent apoptosis
2006
10 pages, 5 figures.-- PMID: 16341125 [PubMed].-- Available online Dec 9, 2005.
The crystal structure of a 250-kDa heterotetrameric particle explains inhibition of sheddase meprin β by endogenous fetuin-B
2021
Meprin β (Mβ) is a multidomain type-I membrane metallopeptidase that sheds membrane-anchored substrates, releasing their soluble forms. Fetuin-B (FB) is its only known endogenous protein inhibitor. Herein, we analyzed the interaction between the ectodomain of Mβ (MβΔC) and FB, which stabilizes the enzyme and inhibits it with subnanomolar affinity. The MβΔC:FB crystal structure reveals a ∼250-kDa, ∼160-Å polyglycosylated heterotetrameric particle with a remarkable glycan structure. Two FB moieties insert like wedges through a “CPDCP trunk” and two hairpins into the respective peptidase catalytic domains, blocking the catalytic zinc ions through an “aspartate switch” mechanism. Uniquely, the …
Deregulation of the EGFR/PI3K/PTEN/Akt/mTORC1 pathway in breast cancer: possibilities for therapeutic intervention
2014
// Nicole M. Davis 1 , Melissa Sokolosky 1 , Kristin Stadelman 1 , Stephen L. Abrams 1 , Massimo Libra 2 , Saverio Candido 2 , Ferdinando Nicoletti 2 , Jerry Polesel 3 , Roberta Maestro 4 , Antonino D’Assoro 5 , Lyudmyla Drobot 6 , Dariusz Rakus 7 , Agnieszka Gizak 7 , Piotr Laidler 8 , Joanna Dulinska-Litewka 8 , Joerg Basecke 9 , Sanja Mijatovic 10 , Danijela Maksimovic-Ivanic 10 , Giuseppe Montalto 11,12 , Melchiorre Cervello 12 , Timothy L. Fitzgerald 13 , Zoya N. Demidenko 14 , Alberto M. Martelli 15 , Lucio Cocco 15 , Linda S. Steelman 1 and James A. McCubrey 1 1 Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University Greenville, NC 27858 USA 2 …
Htid-1, the human homolog of the Drosophila melanogaster l(2)tid tumor suppressor, defines a novel physiological role of APC.
2007
Htid-1, the human counterpart of the Drosophila tumor suppressor gene lethal(2)tumorous imaginal discs (l(2)tid) encodes three splice forms translated into three cytosolic - Tid50, Tid48 and Tid46 - and three mitochondrial - Tid43, Tid40 and Tid38 - proteins. Here we provide evidence for the association of the endogenous Tid50/Tid48 proteins with the adenomatous polyposis coli (APC) tumor suppressor in normal colon epithelium, colorectal cancer cells and mouse NIH3T3 fibroblasts. Using the Glutathione S-transferase binding assay we show that the N-terminal region including the Armadillo domain (ARM) of APC is sufficient to bind the Tid molecules. Using immunoprecipitation and confocal micro…
Phosphorylation of Elp1 by Hrr25 is required for elongator-dependent tRNA modification in yeast.
2014
Elongator is a conserved protein complex comprising six different polypeptides that has been ascribed a wide range of functions, but which is now known to be required for modification of uridine residues in the wobble position of a subset of tRNAs in yeast, plants, worms and mammals. In previous work, we showed that Elongator's largest subunit (Elp1; also known as Iki3) was phosphorylated and implicated the yeast casein kinase I Hrr25 in Elongator function. Here we report identification of nine in vivo phosphorylation sites within Elp1 and show that four of these, clustered close to the Elp1 C-terminus and adjacent to a region that binds tRNA, are important for Elongator's tRNA modification…
Promoter architecture and transcriptional regulation of Abf1-dependent ribosomal protein genes inSaccharomyces cerevisiae
2016
In Saccharomyces cerevisiae, ribosomal protein gene (RPG) promoters display binding sites for either Rap1 or Abf1 transcription factors. Unlike Rap1-associated promoters, the small cohort of Abf1-dependent RPGs (Abf1-RPGs) has not been extensively investigated. We show that RPL3, RPL4B, RPP1A, RPS22B and RPS28A/B share a common promoter architecture, with an Abf1 site upstream of a conserved element matching the sequence recognized by Fhl1, a transcription factor which together with Ifh1 orchestrates Rap1-associated RPG regulation. Abf1 and Fhl1 promoter association was confirmed by ChIP and/or gel retardation assays. Mutational analysis revealed a more severe requirement of Abf1 than Fhl1 …
Regulation of the hDlg/hScrib/Hugl-1 tumour suppressor complex.
2008
The proper function of the Scribble tumour suppressor complex is dependent upon the correct localisation of its components. Previously we observed dynamic relocalisation of the hDlg component under conditions of osmotic stress. We now show that the other two components of the complex, hScrib and Hugl-1 display similar patterns of expression. We demonstrate, by shRNA ablation of hScrib expression, that hDlg and Hugl-1 are in part dependent upon hScrib for their correct localization. However under conditions of osmotic stress this apparent dependency no longer exists: hDlg and Hugl-1 localise to cell membranes independently of hScrib. We also demonstrate an interaction between the three compo…
Modular organization in the reductive evolution of protein-protein interaction networks
2006
Analysis of the reduction in genome size of Buchnera aphidicola from its common ancestor E. coli shows that the organization of networks into modules is the property that seems to be directly related with the evolutionary process of genome reduction.
Common gene expression strategies revealed by genome-wide analysis in yeast
2007
A comprehensive analysis of six variables characterizing gene expression in yeast, including transcription and translation, mRNA and protein amounts, reveals a general tendency for levels of mRNA and protein to be harmonized, and for functionally related genes to have similar values for these variables.
In human endothelial cells rapamycin causes mTORC2 inhibition and impairs cell viability and function.
2008
Aim Drug-eluting stents are widely used to prevent restenosis but are associated with late endothelial damage. To understand the basis for this effect, we have studied the consequences of a prolonged incubation with rapamycin on the viability and functions of endothelial cells. Methods and results Human umbilical vein or aorta endothelial cells were exposed to rapamycin in the absence or in the presence of tumour necrosis factor α (TNFα). After a 24 h-incubation, rapamycin (100 nM) caused a significant cell loss associated with the increase of both apoptosis and necrosis, as quantified by propidium iodide staining, caspase 3 activity, and lactate dehydrogenase release. Rapamycin also impair…