Disease relevance of ESCO2

• Inactivating mutations in ESCO2 cause SC phocomelia and Roberts syndrome: no phenotype-genotype correlation [1].
• To determine whether ESCO2 mutations are also responsible for SC, we studied three families with SC and two families in which variable degrees of limb and craniofacial abnormalities, detected by fetal ultrasound, led to pregnancy terminations [1].
• Mutations in the cohesin regulators NIPBL and ESCO2 are causative of the Cornelia de Lange syndrome (CdLS) and Roberts or SC phocomelia syndrome, respectively [2].
• Addition of the iron-sulphur cluster nitrosyl Roussin's black salt (RBS, heptanitrosyl-tri-mu3-thioxotetraferrate (1-)) resulted in a rapid and dose-dependent (50-250 microM) decline in the electrical resistance displayed by co-cultures of vascular endothelial cells and C6 glioma cells [3].
• The markers were also cloned downstream to a modified promoterless Escherichia coli gusA gene (containing TGA stop codons in all three reading frames prior to its RBS and start codon) to construct the CAS-GNm (gusA-Ptac-nptII-TtrpA) or CAS-GGm (gusA-Ptac/PaacCI-aacCI-TtrpA) cassettes [4].

High impact information on ESCO2

• The ESCO2 protein product is a member of a conserved protein family that is required for the establishment of sister chromatid cohesion during S phase and has putative acetyltransferase activity [5].
• A monoclonal antibody, RBS, blocked HCV-229E virus infection of human lung fibroblasts, immunoprecipitated aminopeptidase N and inhibited its enzymatic activity [6].
• A mutant aminopeptidase lacking the catalytic site of the enzyme did not bind HCV-229E or RBS and did not render murine cells susceptible to HCV-229E infection, suggesting that the virus-binding site may lie at or near the active site of the human aminopeptidase molecule [6].
• We identified seven novel mutations in exons 3-8 of ESCO2 [1].
• Reduction of cohesin relieves the Wapl-depletion phenotype, and depletion of Wapl rescues premature sister separation observed in Sgo1-depleted or Esco2-depleted cells [7].

Biological context of ESCO2

• Having established that RBS and SC are caused by mutations in the same gene, we delineated the clinical phenotype of the tetraphocomelia spectrum that is associated with HR and ESCO2 mutations and differentiated it from other types of phocomelia that are negative for HR [1].
• A homozygous frameshift mutation in the ESCO2 gene: evidence of intertissue and interindividual variation in Nmd efficiency [8].
• In mitosis, EFO1 is phosphorylated, whereas EFO2 is degraded [9].
• The difference between EFO1 and EFO2 also is reflected in their cell cycle regulation [9].
• We propose that EFO1 and EFO2 are targeted to different chromosome structures to help establish or maintain sister-chromatid cohesion [9].

Anatomical context of ESCO2

• We performed mutational analysis of the ESCO2 gene in two fetuses diagnosed with RS and their normal parents [8].
• Considering the position of the mutation identified, we carried out qualitative and quantitative real-time ESCO2 cDNA analysis on RNA isolated from CVS-stromal cells in one fetus, amniocytes in the second fetus, and lymphocytes from the heterozygous parents [8].
• We conclude that nitric oxide liberated from RBS results in a reversible diminution in the integrity of the endothelial cell barrier in the co-culture system, and we suggest that light-sensitive endogenous nitric oxide generator compounds may be present in intact cells [3].
• DNA damage was more severe in rat islet cells exposed to similar amounts of RBS [10].
• The possibility is discussed that lack of NK cells may lead to the development of RBS aplasia if NK cells play a role in promoting the production of RBC [11].

Associations of ESCO2 with chemical compounds

• In contrast, the nitric oxide synthase inhibitor nitro-L-arginine methyl ester (250 microM) caused no inhibition in the decline in resistance of RBS-exposed cultures [3].
• RBS density (phthalate-oil method) and RBC deformability (RBC elongation in a counter-rotating rheoscope) were studied in seven children with TEC and in 10 control children [12].
• The results justify the hypothesis of the adduct formation and show that only in case of S-ligands the higher contribution of the Fe(III)-NO(-) components in adduct than in RBS is observed, which on excitation can undergo heterolytic cleavage yielding Fe(III) and NO(-), converted rapidly into N(2)O [13].
• XPS, RBS, and AFM studies confirm the formation of a monolayer of 11 on the alumina surface [14].
• RBS analysis at a maximum resolution depth of 1000 nm, indicated a decrease of the total thickness of TiO2 after one year of IMZ implantation [15].

Analytical, diagnostic and therapeutic context of ESCO2

• Moreover, considering that a mutated full length mRNA was produced in both fetuses, we used Western blot analysis to demonstrate the absence of the ESCO2-truncated protein in cells derived from both fetuses and in a lymphoblastoid cell line derived from the parents [8].
• Exposure of human or rat islets to RBS was associated with significant DNA strand breakage, as judged by the comet assay (single cell gel electrophoresis) and by ultrastructural signs of cell damage [10].
• Finally, RBS, although scarcely used to date in any biological context, is clearly a powerful way of measuring major elemental ratios in mineralised tissues; however, RBS lacks the resolving power of PIXE and so is not a candidate for multi-trace element analysis [16].
• Two bioreactor cultivations were performed in a BIOSTAT(R) Bplus RBS (rotating bed system) 500 on Sponceram carrier discs [17].
• UV-VIS, Raman spectroscopy, RBS (Rutherford backscattering) and ERDA (Elastic Recoil Detection Analysis) techniques were used for the characterization of the layers [18].

References