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71.
Argyris Demetrius Kaliafas Vassilis John Marmaras Constantin Christodoulou 《Development genes and evolution》1984,194(1):37-43
Summary The developmental profile of the major haemolymph proteins (ceratitins) inCeratitis capitata was studied. Ceratitin concentration in the haemolymph decreases dramatically during the last days of pupal life, while the amounts of ceratitins in whole organism extracts remain unchanged. By electrophoretic, immunological and immunofluorescence techniques it was revealed that ceratitins are reabsorbed by the fat body and a fraction of them is deposited in the cuticle. The possible role of ceratitins is discussed. 相似文献
72.
Ioanna Sevastou Eleanna KaffeMarios-Angelos Mouratis Vassilis Aidinis 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(1):42-60
Lysophosphatidylcholine (LPC) and lysophosphatidic acid (LPA), the most prominent lysoglycerophospholipids, are emerging as a novel class of inflammatory lipids, joining thromboxanes, leukotrienes and prostaglandins with which they share metabolic pathways and regulatory mechanisms. Enzymes that participate in LPC and LPA metabolism, such as the phospholipase A2 superfamily (PLA2) and autotaxin (ATX, ENPP2), play central roles in regulating LPC and LPA levels and consequently their actions. LPC/LPA biosynthetic pathways will be briefly presented and LPC/LPA signaling properties and their possible functions in the regulation of the immune system and chronic inflammation will be reviewed. Furthermore, implications of exacerbated LPC and/or LPA signaling in the context of chronic inflammatory diseases, namely rheumatoid arthritis, multiple sclerosis, pulmonary fibrosis and hepatitis, will be discussed. This article is part of a Special Issue entitled Advances in Lysophospholipid Research. 相似文献
73.
Marc J. A. Bailey Vassilis Koronakis Thomas Schmoll Colin Hughes 《Molecular microbiology》1992,6(8):1003-1012
74.
Independent interaction of the acyltransferase HlyC with two maturation domains of the Escherichia coli toxin HlyA 总被引:1,自引:0,他引:1
The apparently unique fatty acylation mechanism that underlies activation (maturation) of Escherichia coli haemolysin and related toxins is further clarified by investigation of the interaction of protoxin with the specific acyltransferase HlyC. Using deleted protoxin variants and protoxin peptides as substrates in an in vitro maturation reaction dependent upon HlyC and acyl-acyl carrier protein, two independent HlyC recognition domains were identified on the 1024-residue protoxin, proA, and they were shown to span the two target lysine residues K564 (KI) and K690 (KII) that are fatty acylated. Each domain required 15–30 amino acids for basal recognition and 50–80 amino acids for wild-type acylation. The two domains (FAI and FAII) competed with each other in cis and in trans for HlyC. The affinity of FAI for HlyC is approximately four times greater than that of FAII resulting in an overall 80% acylation at KI and 20% acylation at KII in both whole toxin and peptide derivatives. No other proA sequences were required for toxin maturation, and excess Ca2+ prevented acylation of both lysines. The lack of primary sequence identity between FAI and FAll domains in proA and among corresponding sites on related protoxins currently precludes an explanation of the basis of HlyC recognition by proA. 相似文献
75.
Aristidis S. Veskoukis Antonios Kyparos Vassilis Paschalis Michalis G. Nikolaidis 《Biomarkers》2016,21(3):208-217
The assessment of redox status is most frequently performed by measuring redox biomarkers. The spectrophotometer is the most commonly used analytical instrument in biochemistry. There is a huge number of spectrophotometric redox biomarkers and assays, thus distinguishing the most appropriate biomarkers and protocols is overwhelming. The aim of the present review is to propose valid and reliable spectrophotometric assays for measuring redox biomarkers in blood. It is hoped that this work will help researchers to select the most suitable redox biomarkers and assays. 相似文献
76.
Lisa Del Bel Belluz Riccardo Guidi Ioannis S. Pateras Laura Levi Boris Mihaljevic Syed Fazle Rouf Marie Wrande Marco Candela Silvia Turroni Claudia Nastasi Clarissa Consolandi Clelia Peano Toma Tebaldi Gabriella Viero Vassilis G. Gorgoulis Thorbj?rn Krejsgaard Mikael Rhen Teresa Frisan 《PLoS pathogens》2016,12(4)
77.
78.
Minas V Mylonas I Schiessl B Mayr D Schulze S Friese K Jeschke U Makrigiannakis A 《Histochemistry and cell biology》2007,128(1):55-63
Lewis antigens belong to the blood group of antigens and mediate cellular adhesion through interaction with selectins. Invasive
trophoblasts use an array of adhesion molecules to facilitate cell–cell and cell–extracellular matrix interactions. Here,
we examined immunohistochemically the expression of Sialyl Lewis a (sLea), Sialyl Lewis x (sLex) and Lewis y (Ley) in term placentas obtained from cases of normal, intrauterine growth retardation (IUGR), preeclamptic (PE) and hemolysis,
elevated liver enzymes and low platelets syndrome (HELLP) pregnancies. We report the expression of sLex in third trimester extravillous trophoblasts (EVT). sLex was significantly decreased in IUGR and moderately decreased in PE compared to normal placentas. sLex was additionally found in syncytiotrophoblast, without however any significant differences in staining intensity between
normal and pathological cases. sLea was restricted to amnion epithelium. Finally, Ley was expressed in cytotrophoblasts and villous endothelial cells. Ley expression was significantly upregulated in IUGR and HELLP, whereas there was a trend toward increase in PE compared to normal
placentas. The present study suggests that downregulation of sLex in EVT might be associated with IUGR and PE. Furthermore, Ley, which was recently described as a potent angiogenic factor, is upregulated in placental villi in conditions associated with
placental malperfusion.
U. Jeschke and A. Makrigiannakis have contributed equally. 相似文献
79.
Thorsten Mosler H Irem Baymaz Justus F Grf Ivan Mikicic Georges Blattner Edward Bartlett Matthias Ostermaier Rossana Piccinno Jiwen Yang Andrea Voigt Marco Gatti Stefania Pellegrino Matthias Altmeyer Katja Luck Ivan Ahel Vassilis Roukos Petra Beli 《Nucleic acids research》2022,50(20):11600
PARP1 mediates poly-ADP-ribosylation of proteins on chromatin in response to different types of DNA lesions. PARP inhibitors are used for the treatment of BRCA1/2-deficient breast, ovarian, and prostate cancer. Loss of DNA replication fork protection is proposed as one mechanism that contributes to the vulnerability of BRCA1/2-deficient cells to PARP inhibitors. However, the mechanisms that regulate PARP1 activity at stressed replication forks remain poorly understood. Here, we performed proximity proteomics of PARP1 and isolation of proteins on stressed replication forks to map putative PARP1 regulators. We identified TPX2 as a direct PARP1-binding protein that regulates the auto-ADP-ribosylation activity of PARP1. TPX2 interacts with DNA damage response proteins and promotes homology-directed repair of DNA double-strand breaks. Moreover, TPX2 mRNA levels are increased in BRCA1/2-mutated breast and prostate cancers, and high TPX2 expression levels correlate with the sensitivity of cancer cells to PARP-trapping inhibitors. We propose that TPX2 confers a mitosis-independent function in the cellular response to replication stress by interacting with PARP1. 相似文献
80.
Fadouloglou VE Deli A Glykos NM Psylinakis E Bouriotis V Kokkinidis M 《The FEBS journal》2007,274(12):3044-3054
Bacillus cereus is an opportunistic pathogenic bacterium closely related to Bacillus anthracis, the causative agent of anthrax in mammals. A significant portion of the B. cereus chromosomal genes are common to B. anthracis, including genes which in B. anthracis code for putative virulence and surface proteins. B. cereus thus provides a convenient model organism for studying proteins potentially associated with the pathogenicity of the highly infectious B. anthracis. The zinc-binding protein of B. cereus, BcZBP, is encoded from the bc1534 gene which has three homologues to B. anthracis. The protein exhibits deacetylase activity with the N-acetyl moiety of the N-acetylglucosamine and the diacetylchitobiose and triacetylchitotriose. However, neither the specific substrate of the BcZBP nor the biochemical pathway have been conclusively identified. Here, we present the crystal structure of BcZBP at 1.8 A resolution. The N-terminal part of the 234 amino acid protein adopts a Rossmann fold whereas the C-terminal part consists of two beta-strands and two alpha-helices. In the crystal, the protein forms a compact hexamer, in agreement with solution data. A zinc binding site and a potential active site have been identified in each monomer. These sites have extensive similarities to those found in two known zinc-dependent hydrolases with deacetylase activity, MshB and LpxC, despite a low degree of amino acid sequence identity. The functional implications and a possible catalytic mechanism are discussed. 相似文献