The body temperature is considered a universal cue by which the master clock synchronizes the peripheral clocks in mammals, but the mechanism is not fully understood. Here we identified two cold-induced RNA-binding proteins (RBPs), Cirbp and Rbm3, as important regulators for the temperature entrained circadian gene expression. The depletion of Cirbp or Rbm3 significantly reduced the amplitudes of core circadian genes. PAR-CLIP analyses showed that the 3′UTR binding sites of Cirbp and Rbm3 were significantly enriched near the polyadenylation sites (PASs). Furthermore, the depletion of Cirbp or Rbm3 shortened 3′UTR, whereas low temperature (upregulating Cirbp and Rbm3) lengthened 3′UTR. Remarkably, we found that they repressed the usage of proximal PASs by binding to the common 3′UTR, and many cases of proximal/distal PAS selection regulated by them showed strong circadian oscillations. Our results suggested that Cirbp and Rbm3 regulated the circadian gene expression by controlling alternative polyadenylation (APA).

BackgroundIn the last few decades, several groups have observed that proteins expressed as inclusion bodies (IBs) in bacteria could still be biologically active when terminally fused to an appropriate aggregation-prone partner such as pyruvate oxidase from Paenibacillus polymyxa (PoxB). More recently, we have demonstrated that three amphipathic self-assembling peptides, an alpha helical peptide 18A, a beta-strand peptide ELK16, and a surfactant-like peptide L6KD, have properties that induce target proteins into active IBs. We have developed an efficient protein expression and purification approach for these active IBs by introducing a self-cleavable intein molecule.ResultsIn this study, the self-assembling peptide GFIL8 (GFILGFIL) with only hydrophobic residues was analyzed, and this peptide effectively induced the formation of cytoplasmic IBs in Escherichia coli when terminally attached to lipase A and amadoriase II. The protein aggregates in cells were confirmed by transmission electron microscopy analysis and retained ~50% of their specific activities relative to the native counterparts. We constructed an expression and separation coupled tag (ESCT) by incorporating an intein molecule, the Mxe GyrA intein. Soluble target proteins were successfully released from active IBs upon cleavage of the intein between the GFIL8 tag and the target protein, which was mediated by dithiothreitol. A variant of GFIL8, GFIL16 (GFILGFILGFILGFIL), improved the ESCT scheme by efficiently eliminating interference from the soluble intein-GFIL8 molecule. The yields of target proteins at the laboratory scale were 3.0–7.5 μg/mg wet cell pellet, which is comparable to the yields from similar ESCT constructs using 18A, ELK16, or the elastin-like peptide tag scheme.ConclusionsThe all-hydrophobic self-assembling peptide GFIL8 induced the formation of active IBs in E. coli when terminally attached to target proteins. GFIL8 and its variant GFIL16 can act as a “pull-down” tag to produce purified soluble proteins with reasonable quantity and purity from active aggregates. Owing to the structural simplicity, strong hydrophobicity, and high aggregating efficiency, these peptides can be further explored for enzyme production and immobilization.

No abstract

Objective. Adropin is a newly identified regulatory protein encoded by the Enho gene and is critically involved in energy homeostasis and insulin sensitivity. This study aims to determine the correlation of serum adropin concentrations with diabetic nephropathy (DN). Methods. This study consisted of 245 patients with type 2 diabetes mellitus (T2DM) and 81 healthy subjects. Then T2DM patients were divided into normoalbuminuria, microalbuminuria, and macroalbuminuria subgroups based on urine albumin to creatinine ratio (ACR). Results. T2DM patients showed significantly lower serum adropin concentrations than those in the controls. T2DM patients with macroalbuminuria had significantly decreased serum adropin concentrations compared with the other three groups. In addition, T2DM patients with microalbuminuria showed lower serum adropin concentrations than those in patients with normoalbuminuria. Logistic regression analysis showed that serum adropin was correlated with decreased risk of developing T2DM and DN. Pearson correlation analysis indicated that serum adropin was negatively correlated with body mass index (BMI), blood urea nitrogen, creatinine, and ACR and positively correlated with glomerular filtration rate. Furthermore, multiple linear regression analysis showed that BMI and ACR were negatively correlated with serum adropin levels. Conclusion. Serum adropin concentrations are negatively associated with renal function. Adropin may be implicated in the pathogenesis of DN development.

Objective: Irisin, a recently identified myokine, is involved in the protection of mice against obesity and diabetes. This study aims to determine the serum and vitreous concentrations of irisin in patients with diabetic nephropathy and diabetic retinopathy. Methods: A total of 178 patients with type 2 diabetes mellitus, as well as 22 type 2 diabetes mellitus patients without diabetic retinopathy and 35 patients with proliferative diabetic retinopathy were enrolled in this study. Results: Serum irisin concentrations were significantly elevated in the control group compared with those in type 2 diabetes mellitus patients. Furthermore, type 2 diabetes mellitus patients with macroalbuminuria exhibited significantly lower serum irisin concentrations than the controls and type 2 diabetes mellitus patients with normoalbuminuria and microalbuminuria. Simple regression analysis showed that the serum irisin concentrations in type 2 diabetes mellitus patients were negatively correlated with age, fasting plasma glucose, homeostasis model assessment of insulin resistance, blood urea nitrogen, creatinine, and positively correlated with creatinine clearance and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers treatment. Proliferative diabetic retinopathy patients showed significantly decreased serum and vitreous irisin concentrations compared with the control group and type 2 diabetes mellitus patients without diabetic retinopathy. Furthermore, decreased serum and vitreous irisin concentrations were found in type 2 diabetes mellitus patients without diabetic retinopathy than those in the controls. Conclusion: Irisin concentrations are associated with the presence of diabetic nephropathy and diabetic retinopathy.

analysis of miRNAs in an extreme mammalian hibernator, the Arctic ground squirrel.

Chemerin is shown to be associated with inflammation which is involved in the pathogenesis of diabetic nephropathy. This study aims to determine whether rosiglitazone and pioglitazone ameliorate renal function through an effect on the expression of chemerin and ChemR23 in streptozotocin-induced diabetic rats. The rats were randomized to control, diabetic, rosiglitazone-, and pioglitazone-treated groups. The expression level of chemerin and ChemR23 in the renal tissues was significantly elevated in the diabetic group compared with the control group. Rosiglitazone inhibited the overexpression of chemerin and ChemR23, while pioglitazone inhibited the overexpression of ChemR23 in the kidney of diabetic rats. In addition, chemerin expression level was positively correlated with transforming growth factor-β1, connective tissue growth factor, tumor necrosis factor-α, and intracellular cell adhesion molecule-1 expression in diabetic rats. Rosiglitazone ameliorates diabetic nephropathy by reducing the expression of chemerin and ChemR23 in diabetic rats.

Objective Adropin, a newly identified regulatory protein encoded by Enho gene, is correlated with insulin sensitivity and diabetes. The aim of this study is to determine whether serum and vitreous adropin concentrations are correlated with the presence of diabetic retinopathy. Methods A population of 165 patients with type 2 diabetes mellitus (52 without diabetic retinopathy, 69 with non-proliferative diabetic retinopathy and 44 patients with proliferative diabetic retinopathy) was enrolled in this study. The control group enrolled 68 healthy subjects who had underwent vitrectomy for retinal detachment. Serum and vitreous adropin concentrations were examined using enzyme-linked immunosorbent assay method. Results Control subjects had significantly higher serum and vitreous adropin concentrations compared with diabetic patients. Serum and vitreous adropin concentrations in proliferative diabetic retinopathy patients were significantly reduced compared with those in non-proliferative diabetic retinopathy patients and type 2 diabetes mellitus patients without diabetic retinopathy. In addition, there were lower serum and vitreous adropin concentrations in non-proliferative diabetic retinopathy patients compared with type 2 diabetes mellitus patients without diabetic retinopathy. Logistic regression analysis revealed that serum and vitreous adropin were associated with a decreased risk of type 2 diabetes mellitus and diabetic retinopathy. Conclusion Serum and vitreous adropin concentrations are negatively associated with the presence of diabetic retinopathy.