We tested whether DNA-methylation profiles account for inter-individual variation in body mass index (BMI) and height and whether they predict these phenotypes over and above genetic factors. Genetic predictors were derived from published summary results from the largest genome-wide association studies on BMI (n ∼ 350,000) and height (n ∼ 250,000) to date. We derived methylation predictors by estimating probe-trait effects in discovery samples and tested them in external samples. Methylation profiles associated with BMI in older individuals from the Lothian Birth Cohorts (LBCs, n = 1,366) explained 4.9% of the variation in BMI in Dutch adults from the LifeLines DEEP study (n = 750) but did not account for any BMI variation in adolescents from the Brisbane Systems Genetic Study (BSGS, n = 403). Methylation profiles based on the Dutch sample explained 4.9% and 3.6% of the variation in BMI in the LBCs and BSGS, respectively. Methylation profiles predicted BMI independently of genetic profiles in an additive manner: 7%, 8%, and 14% of variance of BMI in the LBCs were explained by the methylation predictor, the genetic predictor, and a model containing both, respectively. The corresponding percentages for LifeLines DEEP were 5%, 9%, and 13%, respectively, suggesting that the methylation profiles represent environmental effects. The differential effects of the BMI methylation profiles by age support previous observations of age modulation of genetic contributions. In contrast, methylation profiles accounted for almost no variation in height, consistent with a mainly genetic contribution to inter-individual variation. The BMI results suggest that combining genetic and epigenetic information might have greater utility for complex-trait prediction. 相似文献
Epidermal fatty acid‐binding protein (E‐FABP/FABP5/DA11) binds and transport long‐chain fatty acids in the cytoplasm and may play a protecting role during neuronal injury. We examined whether E‐FABP protects nerve growth factor‐differentiated PC12 cells (NGFDPC12 cells) from lipotoxic injury observed after palmitic acid (C16:0; PAM) overload. NGFDPC12 cells cultures treated with PAM/bovine serum albumin at 0.3 mM/0.15 mM show PAM‐induced lipotoxicity (PAM‐LTx) and apoptosis. The apoptosis was preceded by a cellular accumulation of reactive oxygen species (ROS) and higher levels of E‐FABP. Antioxidants MCI‐186 and N‐acetyl cysteine prevented E‐FABP's induction in expression by PAM‐LTx, while tert‐butyl hydroperoxide increased ROS and E‐FABP expression. Non‐metabolized methyl ester of PAM, methyl palmitic acid (mPAM), failed to increase cellular ROS, E‐FABP gene expression, or trigger apoptosis. Treatment of NGFDPC12 cultures with siE‐FABP showed reduced E‐FABP levels correlating with higher accumulation of ROS and cell death after exposure to PAM. In contrast, increasing E‐FABP cellular levels by pre‐loading the cells with recombinant E‐FABP diminished the PAM‐induced ROS and cell death. Finally, agonists for PPARβ (GW0742) or PPARγ (GW1929) increased E‐FABP expression and enhanced the resistance of NGFDPC12 cells to PAM‐LTx. We conclude that E‐FABP protects NGFDPC12 cells from lipotoxic injury through mechanisms that involve reduction of ROS.
The codon modified neutral endo-β-1,4-glucanase gene celEn, originating from the anaerobic fungus Orpinomyces sp. strain PC-2, was inserted between the strong promoter Pcel7A and the terminator Tcel7A from Trichoderma reesei. The resulting expression cassette was ligated to the pCAMBIA1300 Agrobacterium binary vector to construct pCB-hE that also contains a hygromycin B resistance marker. pCB-hE was introduced into T. reesei ZU-02 through an Agrobacterium tumefaciens–mediated transformation procedure that has been modified with an improved transformation efficiency of 12,500 transformants
per 107 conidia. Stable integration of the celEn gene into the chromosomal DNA of T. reesei ZU-02 was confirmed by PCR. After 48 h fermentation in shaking flasks, the endo-β-1,4-glucanase activities increased to 55–70 IU ml−1 in transgenic strains, which were about 6–7 times higher than that of the original ZU-02 strain (9.5 IU ml−1). When the avicel was added in fermentation medium, the endo-β-1,4-glucanase activity in the transgenic strains could be
further increased to 193.6 IU ml−1 after 84 h fermentation. Transgenic T. reesei strains with high neutral endo-β-1,4-glucanase activity will be particularly suitable for certain applications in textile
industry. The improved procedures for overproduction and secretion of heterologous proteins in transgenic T. reesei can also be used to generate similar recombinant proteins for research or industrial purposes. 相似文献
α-Amylase from Aspergillus oryzae was covalently immobilized onto polystyrene pellets with pentaethylenehexamine (PS-PEHA-Ald) and pentaethylene glycol (PS-PG-Ald) carrying a terminal aldehyde group. Optimum immobilization occured at pH 8.0 and 25 °C, and at pH 7.0 and 35 °C for PS-PEHA-Ald and PS-PG-Ald, respectively. PS-PEHA-Ald immobilized enzyme retained approximately 75% of the initial activity over 45 days of storage, 70% of the initial activity after nine runs of recycling and displayed the better resistance to detrimental metal ions. PS-PG-Ald immobilized enzyme retained approximately 50% of the initial activity in 8h at 70 °C. The catalytic efficiencies of PS-PEHA-Ald immobilized and PS-PG-Ald immobilized amylase were 1.42 and 1.29 times higher than that of native enzyme. The activation energy of the reaction mediated by the amylase was reduced by 58.1% and 57.3% when PS-PEHA-Ald and PS-PG-Ald used as support respectively. 相似文献
The cellobiase gene from Aspergillus niger was cloned and connected with the strong promoter Pcbh1 from Trichoderma reesei to construct a recombinant plasmid pHB9 with the hygromycin B resistance marker. The plasmid was transformed into conidia of T. reesei using the modified PEG-CaCl2 method. Main factors effecting the transformation were discussed and about 99-113 transformants/μg DNA could be obtained under optimal conditions. It was found that the molecular mass of the recombinant cellobiase was about 120 kDa by SDS-PAGE analysis. The activity of cellobiase could reach 5.3 IU/ml after 48 h fermentation, which was as high as 106 times compared with that of the host strain. Meanwhile, the filter paper activity of recombinant T. reesei was 1.44-fold of the host strain. Saccharification of corncob residue with the crude enzyme showed that the hydrolysis yield (84.2%) of recombinant T. reesei was 21% higher than that (69.5%) of the host strain. 相似文献
The present work describes a series of novel tetrahydroquinoline amines that potently inhibit the in vitro reuptake of serotonin and dopamine (dual reuptake inhibitors). The compounds are structurally related to a series we disclosed previously, but are improved with respect to cytochrome P-450 enzyme (CYP) and potassium ion channel Kv11.1 (hERG) inhibition and synthetic accessibility. The detailed synthesis and in vitro activity and ADME profile of the compounds is described, which represent a previously undisclosed dual reuptake inhibitor chemotype. 相似文献
Proteins of viral capsid may self-assemble into virus-like particles (VLPs) that can find many biomedical applications such as platform for drug delivery. In this paper, we describe preparation of VLPs by self-assembly of VP6, a rotavirus capsid protein that was chemically conjugated with doxorubicin (DOX), an anticancer drug. VP6 was first highly expressed in E. Coli, followed by purification and renaturation. DOX was then covalently attached to VP6 to form DOX-VP6 (DVP6) conjugates, which were subsequently self-assembled into VLPs under appropriate condition. Next, lactobionic acid (LA) was chemically linked to the surface of the VLPs. We demonstrated that the aforementioned nanosystem shows specific targeting to hepatoma cell line HepG2. The chemically functionalized VLPs, a kind of biological nanoparticles with excellent biocompatibility and biodegradability, can be prepared in large scale from E. Coli through our method, which may find practical applications in biomedicine. 相似文献