Assembly of different length of polyubiquitins on the catalytic cysteine of E2 enzymes without E3 ligase; a novel application of non-reduced/reduced 2-dimensional electrophoresis

AbstractIn this study using non-reduced/reduced 2-dimensional electrophoresis (NR/R-2DE), we clearly demonstrated that E3-independent ubiquitination by Ube2K produced not only unanchored but also Ube2K-linked polyubiquitins through thioester and isopeptide bonds. E3-independent assembly of polyubiquitins on the catalytic cysteine of Ube2K strongly supports the possibility of ‘en bloc transfer’ for polyubiquitination. From the same analyses of E3-independent ubiquitination products by other E2s, we also found that different lengths of polyubiquitins were linked to different E2s through thioester bond; longer chains by Cdc34 like Ube2K, short chains by Ube2g2, and mono-ubiquitin by UbcH10. Our results suggest that E2s possess the different intrinsic catalytic activities for polyubiquitination

High-resolution crystal structure of the non-specific lipid-transfer protein from maize seedlings

AbstractBackground: The movement of lipids between membranes is aided by lipid-transfer proteins (LTPs). Some LTPs exhibit broad specificity, transferring many classes of lipids, and are termed non-specific LTPs (ns-LTPs). Despite their apparently similar mode of action, no sequence homology exists between mammalian and plant ns-LTPs and no three-dimensional structure has been reported for any plant ns-LTP.Results We have determined the crystal structure of ns-LTP from maize seedlings by multiple isomorphous replacement and refined the structure to 1.9 å resolution. The protein comprises a single compact domain with four α-helices and a long C-terminal region. The eight conserved cysteines form four disulfide bridges (assigned as Cys4–Cys52, Cys14–Cys29, Cys30–Cys75, and Cys50–Cys89) resolving the ambiguity that remained from the chemical determination of pairings in the homologous protein from castor bean. Two of the bonds, Cys4–Cys52 and Cys50–Cys89, differ from what would have been predicted from sequence alignment with soybean hydrophobic protein. The complex between maize ns-LTP and hexadecanoate (palmitate) has also been crystallized and its structure refined to 1.8 å resolution.Conclusion The fold of maize ns-LTP places it in a new category of all-α-type structure, first described for soybean hydrophobic protein. In the absence of a bound ligand, the protein has a tunnel-like hydrophobic cavity, which is large enough to accommodate a long fatty acyl chain. In the structure of the complex with palmitate, most of the acyl chain is buried inside this hydrophobic cavity

Parameter-robust linear quadratic Gaussian technique for multi-agent slung load transportation

This paper copes with parameter-robust controller design for transportation system by multiple unmanned aerial vehicles. The transportation is designed in the form of string connection. Minimal state-space realization of slung-load dynamics is obtained by Newtonian approach with spherical coordinates. Linear quadratic Gaussian / loop transfer recovery (LQG/LTR) is implemented to control the position and attitude of all the vehicles and payloads. The controller's robustness against variation of payload mass is improved using parameter-robust linear quadratic Gaussian (PRLQG) method. Numerical simulations are conducted with several transportation cases. The result verifies that LQG/LTR shows fast performance while PRLQG has its strong point in robustness against system variation

Combined Effects of Surface Morphology and Mechanical Straining Magnitudes on the Differentiation of Mesenchymal Stem Cells without Using Biochemical Reagents

Existing studies examining the control of mesenchymal stem cell (MSC) differentiation into desired cell types have used a variety of biochemical reagents such as growth factors despite possible side effects. Recently, the roles of biomimetic microphysical environments have drawn much attention in this field. We studied MSC differentiation and changes in gene expression in relation to osteoblast-like cell and smooth muscle-like cell type resulting from various microphysical environments, including differing magnitudes of tensile strain and substrate geometries for 8 days. In addition, we also investigated the residual effects of those selected microphysical environment factors on the differentiation by ceasing those factors for 3 days. The results of this study showed the effects of the strain magnitudes and surface geometries. However, the genes which are related to the same cell type showed different responses depending on the changes in strain magnitude and surface geometry. Also, different responses were observed three days after the straining was stopped. These data confirm that controlling microenvironments so that they mimic those in vivo contributes to the differentiation of MSCs into specific cell types. And duration of straining engagement was also found to play important roles along with surface geometry

Screening models using multiple markers for early detection of late-onset preeclampsia in low-risk pregnancy

BACKGROUND: Our primary objective was to establish a cutoff value for the soluble fms-like tyrosine kinase 1(sFlt-1)/placental growth factor (PlGF) ratio measured using the Elecsys assay to predict late-onset preeclampsia in low-risk pregnancies. Our secondary objective was to evaluate the ability of combination models using Elecsys data, second trimester uterine artery (UtA) Doppler ultrasonography measurements, and the serum fetoplacental protein levels used for Down’s syndrome screening, to predict preeclampsia. METHODS: This prospective cohort study included 262 pregnant women with a low risk of preeclampsia. Plasma levels of pregnancy-associated plasma protein-A (PAPP-A) and serum levels of alpha-fetoprotein, unconjugated estriol, human chorionic gonadotropin, and inhibin-A were measured, and sFlt-1/PlGF ratios were calculated. All women underwent UtA Doppler ultrasonography at 20 to 24 weeks of gestation. RESULTS: Eight of the 262 women (3.0%) developed late-onset preeclampsia. Receiver operating characteristic curve analysis showed that the third trimester sFlt-1/PlGF ratio yielded the best detection rate (DR) for preeclampsia at a fixed false-positive rate (FPR) of 10%, followed by the second trimester sFlt-1/PlGF ratio, sFlt-1 level, and PlGF level. Binary logistic regression analysis was used to determine the five best combination models for early detection of late-onset preeclampsia. The combination of the PAPP-A level and the second trimester sFlt-1/PlGF ratio yielded a DR of 87.5% at a fixed FPR of 5%, the combination of second and third trimester sFlt-1/PlGF ratios yielded a DR of 87.5% at a fixed FPR of 10%, the combination of body mass index and the second trimester sFlt-1 level yielded a DR of 87.5% at a fixed FPR of 10%, the combination of the PAPP-A and inhibin-A levels yielded a DR of 50% at a fixed FPR of 10%, and the combination of the PAPP-A level and the third trimester sFlt-1/PlGF ratio yielded a DR of 62.5% at a fixed FPR of 10%. CONCLUSIONS: The combination of the PAPP-A level and the second trimester sFlt-1/PlGF ratio, and the combination of the second trimester sFlt-1 level with body mass index, were better predictors of late-onset preeclampsia than any individual marker

Polymorphisms in Genes That Regulate Cyclosporine Metabolism Affect Cyclosporine Blood Levels and Clinical Outcomes in Patients Who Receive Allogeneic Hematopoietic Stem Cell Transplantation

In patients who received allogeneic hematopoietic stem cell transplantation (HSCT), we investigated the correlations between single nucleotide polymorphisms (SNPs) in genes that regulate cyclosporine metabolism and clinical outcomes. All patients received sibling-matched HSCT. DNA samples of patients and donors were analyzed for 4 SNPs: MDR1 +1236C>T (rs1128503), +2677G>T>A (rs2032582), +3435C>T (rs1045642), and CYP3A5 +6986G>A (rs776746). A total of 156 patients (median age 40 years) were analyzed. Nineteen patients received HSCT for nonmalignant disease. The CYP3A5 +6986AA genotype was associated with a high cyclosporine blood level after transplantation. However, this genotype was not related to any particular clinical outcome. In contrast, the MDR1 +1236C>T SNP was correlated with specific clinical outcomes. When neither the donor nor the recipient had the CC genotype of MDR1 +1236, patients had lower creatinine levels (P < .001) and less transplantation-related mortality (TRM) (P = .012). These patients also showed longer overall survival (OS) in both univariate (P = .003) and multivariate (P = .003) analyses. Although the CYP3A5 +6986AA genotype was correlated with a high blood cyclosporine concentration, lack of the MDR1 +1236CC genotype in both the donor and recipient was correlated with less TRM and a longer OS in patients who received allogeneic HSCT

CRISPR RNAs trigger innate immune responses in human cells

Here, we report that CRISPR guide RNAs (gRNAs) with a 5'-triphosphate group (5'-ppp gRNAs) produced via in vitro transcription trigger RNA-sensing innate immune responses in human and murine cells, leading to cytotoxicity. 5'-ppp gRNAs in the cytosol are recognized by DDX58, which in turn activates type I interferon responses, causing up to similar to 80% cell death. We show that the triphosphate group can be removed by a phosphatase in vitro and that the resulting St-hydroxyl gRNAs in complex with Cas9 or Cpfl avoid innate immune responses and can achieve targeted mutagenesis at a frequency of 95% in primary human CD4(+) T cells. These results are in line with previous findings that chemically synthesized sgRNAs with a 5'-hydroxyl group are much more efficient than in vitro-transcribed (IVT) sgRNAs in human and other mammalian cells. The phosphatase treatment of IVT sgRNAs is a cost-effective method for making highly active sgRNAs, avoiding innate immune responses in human cells.