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Complex Subunit (complex + subunit)

Distribution by Scientific Domains
Medical Sciences40%
Life Sciences40%

Selected Abstracts

Vitamin K epoxide reductase complex subunit 1 (VKORC1,) polymorphism influences the anticoagulation response subsequent to vitamin K intake: a pilot study

JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 7 2008
E. A. SCONCE
[source]

The Aspergillus nidulans sldIRAD50 gene interacts with bimEAPC1, a homologue of an anaphase-promoting complex subunit

MOLECULAR MICROBIOLOGY, Issue 1 2005
Iran Malavazi
Summary The Mre11,Rad50,Nbs1 protein complex has emerged as a central component in the human cellular DNA damage response, and recent observations suggest that these proteins are at least partially responsible for the linking of DNA damage detection to DNA repair and cell cycle checkpoint functions. We have identified Aspergillus nidulans sldI1444D mutant in a screen for dynein synthetic lethals. The sldIRAD50 gene was cloned by complementation of the sporulation deficiency phenotype of this mutant. A transversion G,C at the position 2509 (Ala-692-Pro amino acid change) in the sldI1444D mutant causes sensitivity to several DNA-damaging agents. The mutation sldI1 occurs at the CXXC hinge domain of Rad50. We have deleted part of the coiled-coil and few amino acids of the Rad50,Mre11 interaction region and assessed several phenotypic traits in this deletion strain. Besides sensitivity to a number of DNA-damaging agents, this deletion strain is also impaired in the DNA replication checkpoint response, and in ascospore viability. There is no delay of the S-phase when germlings of both sldI RAD50 and mreAMRE11 inactivation strains were exposed to the DNA damage caused by bleomycin. Transformation experiments and Southern blot analysis indicate homologous recombination is dependent on scaANBS1 function in the Mre11 complex. There are epistatic and synergistic interactions between sldI RAD50 and bimEAPC1 at S-phase checkpoints and response to hydroxyurea and UV light. Our results suggest a possible novel feature of the Mre11 complex in A. nidulans, i.e. a relationship with bimE,APC1. [source]

Mutants in DEFECTIVE GLYCOSYLATION, an Arabidopsis homolog of an oligosaccharyltransferase complex subunit, show protein underglycosylation and defects in cell differentiation and growth

THE PLANT JOURNAL, Issue 4 2005
Olivier Lerouxel
Summary A mutant called defective glycosylation1-1 (dgl1-1) was identified in Arabidopsis based on a growth defect of the dark-grown hypocotyl and an abnormal composition of the non-cellulosic cell wall polysaccharides. dgl1-1 is altered in a protein ortholog of human OST48 or yeast WBP1, an essential protein subunit of the oligosaccharyltransferase (OST) complex, which is responsible for the transfer in the ER of the N-linked glycan precursor onto Asn residues of candidate proteins. Consistent with the known function of the OST complex in eukaryotes, the dgl1-1 mutation led to a reduced N-linked glycosylation of the ER-resident protein disulfide isomerase. A second more severe mutant (dgl1-2) was embryo-lethal. Microscopic analysis of dgl1-1 revealed developmental defects including reduced cell elongation and the collapse and differentiation defects of cells in the central cylinder. These defects were accompanied by changes in the non-cellulosic polysaccharide composition, including the accumulation of ectopic callose. Interestingly, in contrast to other dwarf mutants that are altered in early steps of the N -glycan processing, dgl1-1 did not exhibit a cellulose deficiency. Together, these results confirm the role of DGL1 in N-linked glycosylation, cell growth and differentiation in plants. [source]

Proteomic analysis by two-dimensional electrophoresis to identify the normal human chondrocyte proteome stimulated by tumor necrosis factor , and interleukin-1,

ARTHRITIS & RHEUMATISM, Issue 3 2010
Berta Cillero-Pastor
Objective To determine the intracellular proteome of normal human chondrocytes stimulated with interleukin-1, (IL-1,) and tumor necrosis factor , (TNF,) and to ascertain differences in the protein expression patterns of these 2 cytokines. Methods Normal human knee cartilage chondrocytes were incubated for 48 hours without stimulation or stimulated with IL-1, (5 ng/ml) or with TNF, (10 ng/ml). For each culture condition, protein extracts from 4 normal subjects were pooled and resolved using 2-dimensional electrophoresis. Protein spots were visualized with Sypro stain, and qualitative and quantitative analyses were performed using PDQuest software. Protein spots were then identified by mass spectrometry, using matrix-assisted laser desorption ionization,time-of-flight/time-of-flight technology. Results We identified 37 spots by mass spectrometry (MS) or by MS/MS, corresponding to 35 different proteins. In IL-1,,stimulated chondrocytes, IL-1, was found to modulate 22 proteins, as compared with unstimulated chondrocytes. All of these proteins except connective tissue growth factor (CCND2) were up-regulated. Proteins involved in cellular metabolism and energy (23%) that were up-regulated or induced by IL-1, included nicotinamide phosphoribosyltransferase, long-chain fatty acid,coenzyme A ligase 4, ,-aminolevulinic acid dehydratase, triosephosphate isomerase, and an isoform of glyceraldehyde-3-phosphate dehydrogenase. In TNF,-stimulated chondrocytes, TNF, was found to modulate 20 proteins, as compared with unstimulated chondrocytes. All of these except chitinase 3,like 1 (cartilage glycoprotein 39), proteasome activator complex subunit 2, and G3PDH, were up-regulated. Eighteen proteins were differently modulated by IL-1, and TNF,. Of these, 45% were related to metabolism. Conclusion IL-1, and TNF, induce different profiles of intracellular protein expression in healthy human chondrocytes. Most of the proteins that are differently regulated are proteins that are implicated in the generation of cellular energy and in glycolysis. [source]

Identification and characterization of cytochrome bc1 subcomplexes in mitochondria from yeast with single and double deletions of genes encoding cytochrome bc1 subunits

FEBS JOURNAL, Issue 17 2007
Vincenzo Zara
We have examined the status of the cytochrome bc1 complex in mitochondrial membranes from yeast mutants in which genes for one or more of the cytochrome bc1 complex subunits were deleted. When membranes from wild-type yeast were resolved by native gel electrophoresis and analyzed by immunodecoration, the cytochrome bc1 complex was detected as a mixed population of enzymes, consisting of cytochrome bc1 dimers, and ternary complexes of cytochrome bc1 dimers associated with one and two copies of the cytochrome c oxidase complex. When membranes from the deletion mutants were resolved and analyzed, the cytochrome bc1 dimer was not associated with the cytochrome c oxidase complex in many of the mutant membranes, and membranes from some of the mutants contained a common set of cytochrome bc1 subcomplexes. When these subcomplexes were fractionated by SDS/PAGE and analyzed with subunit-specific antibodies, it was possible to recognize a subcomplex consisting of cytochrome b, subunit 7 and subunit 8 that is apparently associated with cytochrome c oxidase early in the assembly process, prior to acquisition of the remaining cytochrome bc1 subunits. It was also possible to identify a subcomplex consisting of subunit 9 and the Rieske protein, and two subcomplexes containing cytochrome c1 associated with core protein 1 and core protein 2, respectively. The analysis of all the cytochrome bc1 subcomplexes with monospecific antibodies directed against Bcs1p revealed that this chaperone protein is involved in a late stage of cytochrome bc1 complex assembly. [source]