Rare variants of HSPB1 are probably associated with amyotrophic lateral sclerosis / 南方医科大学学报

OBJECTIVE@#To explore the association between rare HSPB1 variants and amyotrophic lateral sclerosis (ALS).@*METHODS@#We performed next-generation sequencing for 166 Chinese ALS patients to screen for possible pathogenic rare variants of HSPB1. The control individuals were obtained from 1000 Genome Project and an in-house whole-exome sequencing database. The Sequence Kernel Association Test (SKAT) and the SKAT-optimal test (SKAT-O) were used to identify the association between rare HSPB1 variants and ALS.@*RESULTS@#We identified 3 possible pathogenic rare variants of HSPB1 (all were missenses), including c.379C>T (p.R127W), c.446A>C (p.D149A) and c.451A>C (p.T151P). Compared with 1000 Genome Project, SKAT p=3.61×10@*CONCLUSIONS@#Rare variants of HSPB1 are probably associated with the pathogenesis of ALS.

Propeptide-mediated protein folding: mechanism and its impact on lipase / 生物工程学报

The formation of most proteins consists of two steps: the synthesis of precursor proteins and the synthesis of functional proteins. In these processes, propeptides play important roles in assisting protein folding or inhibiting its activity. As an important polypeptide chain coded by a gene sequence in lipase gene, propeptide usually functions as an intramolecular chaperone, assisting enzyme molecule folding. Meanwhile, some specific sites on propeptide such as glycosylated sites, have important effect on the activity, stability in extreme environment, methanol resistance and the substrate specificity of the lipase. Studying the mechanism of propeptide-mediated protein folding, as well as the influence of propeptide on lipases, will allow to regulate lipase by alternating the propeptide folding behavior and in turn pave new ways for protein engineering research.

Molecular chaperones facilitate soluble expression of recombinant non-toxic mutant CRM197 of diphtheria toxin in Escherichia coli / 生物工程学报

Diphtheria toxin is an ADP-ribosyltransferase toxic to human cells. Mutation of the active site in its catalytic domain eliminates the toxicity, but retains its immunogenicity. A non-toxic mutant of diphtheria toxin known as CRM197 protein has become an ideal carrier protein for conjugate vaccines. CRM197 can further improve its immunogenicity by cross-linking with other antigens, so it has good potential to find broad applications. Unfortunately, inclusion bodies are easily formed during the expression of recombinant CRM197 protein in Escherichia coli, which greatly reduces its yield. In order to address this problem, pG-KJE8 vector carrying molecular chaperones and plasmid pET28a-CRM197, were co-expressed in Escherichia coli. The results showed that the recombinant CRM197 protein was successfully expressed and appeared largely in inclusion bodies. The molecular chaperones DnaK, DnaJ, GrpE, GroES and GroEL5 expressed can facilitate correct and rapid folding of CRM197. Furthermore, it can also improve the recovery rate of soluble CRM197 protein. The soluble expression of CRM197 was maximized upon addition of 1.0 mmol/L IPTG, 0.5 mg L-arabinose, 5.0 ng/mL tetracycline and induction at 20oC for 16 h. The soluble CRM197 protein shows good immunoreactivity, demonstrating the molecular chaperones expressed from pG-KJE8 facilitated the soluble expression of CRM197 protein in E. coli.

Vitamina D, miR-21 y marcadores de apoptosis en pacientes con diabetes tipo I / Vitamin D, miR-21 and apoptosis markers in patients with type 1 diabetes

La diabetes Tipo 1 (DT1) es una compleja enfermedad autoinmune con una etiología aún desconocida. La vitamina D ha sido ampliamente estudiada debido a su potencial terapéutico en los potenciales nuevos casos de DT1. Por otra parte, los microARNs (miRs) han sido propuestos como posibles biomarcadores en diversos procesos biológicos como en la apoptosis e inflamación. El objetivo de este estudio fue evaluar el efecto de la suplementación con vitamina D sobre el perfil de expresión del miR-21 y marcadores de apoptosis tales como: BCL2, STAT3, TIPE2 y DAXX, en células mononucleares periféricas provenientes de pacientes con DT1 y sujetos controles. RESULTADOS: El perfil de expresión de miR-21 se encontró disminuido en los pacientes con DT1 en comparación con los controles. La expresión relativa de BCL2 se encontró aumentada en controles al comparar con pacientes DT1 en todas las condiciones experimentales. La expresión relativa de DAXX mostró un perfil de expresión diferencial al comparar pacientes con DT1 versus controles (p=0.006). CONCLUSIÓN: El estímulo con vitamina D parece tener un posible efecto regulador sobre los genes BCL2 y DAXX.

Type 1 diabetes (T1D) is a complex chronic autoimmune disease. Vitamin D has been one of the most studied therapeutic potential outbreaks related to T1D. Specific miRNAs have been proposed as potential biomarkers in several biological processes as apoptosis and inflammation. The aim of this study was to evaluate the effect of vitamin D on the expression profiles of miR-21 and apoptotic markers BCL2, STAT3, TIPE2 and DAXX, in PBMCs from T1D patients and control subjects. RESULTS: miR-21 expression was increased in controls regarding T1D patients. BCL2 was increased in controls compared to T1D patients in all experimental conditions. DAXX showed different expression patterns between T1D patients and controls (p=0.006). CONCLUSION: Vitamin D showed a possible regulation effect on apoptosis markers mainly through the regulation of BCL2 and DAXX

Clinical features and tubulin folding cofactor E gene analysis in Iranian patients with Sanjad-Sakati syndrome / Características clínicas e análise genética e de cofatores de dobramento da tubulinaem pacientes iranianos com síndrome de Sanjad-Sakati

Abstract Objective Permanent hypoparathyroidism can be presented as part of genetic disorders such as Sanjad-Sakati syndrome (also known as hypoparathyroidism—intellectual disability-dysmorphism), which is a rare autosomal recessive disorder. Our aim was to confirm the diagnosis of a group of patients with dysmorphism, poor growth, and hypoparathyroidism clinically labeled as Sanjad-Sakati syndrome and to identify for the first time the genetic variations on Iranian patients with the same ethnic origin. Methods In this study, 29 cases from 23 unrelated Arab kindreds with permanent hypoparathyroidism and dysmorphism indicating Sanjad-Sakati syndrome were enrolled for 10 years in the southwest of Iran. The mutational analysis by direct sequencing of the tubulin folding cofactor E gene was performed for the patients and their families, as well as their fetuses using genomic DNA. Results Twenty-eight out of 29 cases had parental consanguinity. Twenty-seven cases presented with hypocalcemia seizure and two were referred because of poor weight gain and were found to have asymptomatic hypocalcemia. The dysmorphic features, hypocalcemia in the setting of low to normal parathyroid hormone levels and high phosphorus led to the diagnosis of these cases. Sequencing analysis of the tubulin folding cofactor E gene revealed a homozygous 12-bp deletion (c.155-166del) for all patients. Following that, prenatal diagnosis was performed for eight families, and two fetuses with a homozygous 12-bp deletion were identified. Conclusion These results make it much easier and faster to diagnose this syndrome from other similar dysmorphisms and also help to detect carriers, as well as prenatal diagnosis of Sanjad-Sakati syndrome in high-risk families in this population.

Resumo Objetivo O hipoparatireoidismo permanente pode estar presente como parte das doenças genéticas como na síndrome de Sanjad-Sakati (também chamada de síndrome de hipoparatireoidismo, retardo e dismorfismo), que é um distúrbio autossômico recessivo raro. Nosso objetivo foi confirmar o diagnóstico de um grupo de pacientes com dismorfismo, crescimento deficiente e hipoparatireoidismo clinicamente identificado como síndrome de Sanjad-Sakati e identificar as variações genéticas, pela primeira vez, em pacientes iranianos com a mesma origem étnica. Métodos Neste estudo, foram inscritos 29 casos de 23 famílias árabes sem parentesco com hipoparatireoidismo e dismorfismo indicando síndrome de Sanjad-Sakati, durante 10 anos no sudoeste do Irã. Foi feita a análise mutacional por sequenciamento direto do gene do cofator E de dobramento da tubulina dos pacientes e de suas famílias e também de seus fetos com o DNA genômico. Resultados Apresentaram consanguinidade parental 28 dos 29 casos. Desses, 27 casos apresentaram convulsão por hipocalcemia e dois foram encaminhados devido ao baixo ganho de peso, considerando diagnóstico de hipocalcemia assintomática. As características dismórficas, hipocalcemia na configuração de níveis de hormônio da paratireoide baixos a normais e alto nível de fósforo levaram ao diagnóstico dos casos. A análise de sequenciamento do gene do cofator E de dobramento da tubulina revelou deleção homozigótica de 12 pares de base (pb) (c.155-166del) em todos os pacientes. Após isso, foi feito o diagnóstico pré-natal em oito famílias e dois fetos foram identificados com deleção homozigótica de 12 pb. Conclusão Esses resultados tornam o diagnóstico dessa síndrome muito mais fácil e rápido do que outros dismorfismos semelhantes e também ajudam a detectar portadores, bem como o diagnóstico pré-natal da síndrome de Sanjad-Sakati em famílias de alto risco nessa população.

Effects of non-caloric ultrashort wave on the expression of CoQ10 and C1GALT1C1 in rats with cerebral ischemia reperfusion injury / 中南大学学报(医学版)

OBJECTIVES@#To examine the changes of coenzyme Q10 (CoQ10) and β-galactosyl transferase specific chaperone 1 (C1GALT1C1) in brain of rats with ischemic injury at different time points and to explore the protective mechanism of ultrashort wave (USW) on ischemic brain injury.@*METHODS@#Fifty SD rats were randomly divided into 5 groups (=10 per group): a sham group (control group) and 4 experimental group (ischemia for 2 h). The 4 experimental groups were set as a model 1 d group, a USW 1 d group, a model 3 d group and a USW 3 d group, respectively. Five rats were randomly selected for 2,3,5-triphenyltetrazoliumchloride (TTC) staining in each experimental group, and the remaining 5 rats were subjected to Western blotting and real-time PCR. The percentage of cerebral infarction volume and the relative expression level of CoQ10 and C1GALT1C1 in the brain were examined and compared.@*RESULTS@#The infarct volume percentage after TTC staining was zero in the sham group. With the progress of disease and USW therapy, the infarct volume percentage was decreased in the experimental groups (all <0.05); Western blotting and real-time PCR showed that the relative expression level of CoQ10 in the sham group was the highest, while in the experimental groups, the content of CoQ10 showed a upward trend with the extension of disease and USW therapy, with significant difference (all <0.05). The relative expression level of C1GALT1C1 in the sham group was the lowest, but in the experimental groups, they showed a downward trend with the extension of disease and USW therapy, with significant difference (all <0.05).@*CONCLUSIONS@#Non-caloric USW therapy may upregulate the expression of CoQ10 to suppress the expression of C1GALT1C1 in rats, leading to alleviating cerebral ischemic reperfusion injury.

Traditional and Novel Mechanisms of Heat Shock Protein 90 (HSP90) Inhibition in Cancer Chemotherapy Including HSP90 Cleavage

HSP90 is a molecular chaperone that increases the stability of client proteins. Cancer cells show higher HSP90 expression than normal cells because many client proteins play an important role in the growth and survival of cancer cells. HSP90 inhibitors mainly bind to the ATP binding site of HSP90 and inhibit HSP90 activity, and these inhibitors can be distinguished as ansamycin and non-ansamycin depending on the structure. In addition, the histone deacetylase inhibitors inhibit the activity of HSP90 through acetylation of HSP90. These HSP90 inhibitors have undergone or are undergoing clinical trials for the treatment of cancer. On the other hand, recent studies have reported that various reagents induce cleavage of HSP90, resulting in reduced HSP90 client proteins and growth suppression in cancer cells. Cleavage of HSP90 can be divided into enzymatic cleavage and non-enzymatic cleavage. Therefore, reagents inducing cleavage of HSP90 can be classified as another class of HSP90 inhibitors. We discuss that the cleavage of HSP90 can be another mechanism in the cancer treatment by HSP90 inhibition.

Antiviral and Anti-Inflammatory Activities of Pochonin D, a Heat Shock Protein 90 Inhibitor, against Rhinovirus Infection

Human rhinoviruses (HRV) are one of the major causes of common cold in humans and are also associated with acute asthma and bronchial illness. Heat-shock protein 90 (Hsp90), a molecular chaperone, is an important host factor for the replication of single-strand RNA viruses. In the current study, we examined the effect of the Hsp90 inhibitor pochonin D, in vitro and in vivo, using a murine model of human rhinovirus type 1B (HRV1B) infection. Our data suggested that Hsp90 inhibition significantly reduced the inflammatory cytokine production and lung damage caused by HRV1B infection. The viral titer was significantly lowered in HRV1B-infected lungs and in Hela cells upon treatment with pochonin D. Infiltration of innate immune cells including granulocytes and monocytes was also reduced in the bronchoalveolar lavage (BAL) by pochonin D treatment after HRV1B infection. Histological analysis of the lung and respiratory tract showed that pochonin D protected the mice from HRV1B infection. Collectively, our results suggest that the Hsp90 inhibitor, pochonin D, could be an attractive antiviral therapeutic for treating HRV infection.

MicroRNA-138 regulates cell adhesion-mediated drug resistance phenotype by targeting SGTA in non-Hodgkin's lymphoma / 中华血液学杂志

Objective: To analyze the effects of miR-138 on the expression of small glutamine-rich TPR-containing protein A (SGTA) and cell adhesion-mediated drug resistance (CAM-DR) phenotype in non-Hodgkin's lymphoma (NHL). Methods: The adhesion model was constructed using fibronectin (FN) or bone marrow stromal cells HS-5. The effect of miR-138 on the expression of SGTA was analyzed by Western blotting and RQ-PCR. Dual-luciferase assays were performed to probe the effects of miR-138 on SGTA 3' UTR activities. Subsequently, we investigated the effect of miR-138 on cell cycle, adhesion ability and CAM-DR. Moreover, the correlation between miR-138 expression and therapeutic response was analyzed in 35 paraffin-embedded diffuse large B cell lymphoma samples. Results: Our data showed that adhesion of NHL cells to FN or HS-5 cells significantly increased miR-138 expression (P<0.05). Knockdown of miR-138 markedly increased the protein (all P<0.05) but not for mRNA (all P>0.05) levels of SGTA in NHL cell. The luciferase activity of SGTA 3' UTR was significantly suppressed by miR-138 transfected cells (0.73±0.03 vs 1.00±0.02, t=0.914, P=0.002). No change in terms of reporter activity was observed in SGTA 3'UTR mutant transfected cells (0.93±0.04 vs 1.00±0.02, t=1.375, P=0.241). Also we found that ectopic expression of miR-138 significantly induced cell cycle arrest at G(1) phase in both suspension and adherent cells (all P<0.05). Knockdown of miR-138 had no effect on cell adhesion ability (all P>0.05). More importantly, in suspension cells, knockdown of miR-138 significantly decreased the percentage of doxorubicin-induced cell death. However, knockdown of miR-138 dramatically increased the percentage of doxorubicin-induced cell death in FN/HS-5-adherent cells. Furthermore, the miR-138 expression was significantly higher in patients with progression of disease/stable disease than those experiencing complete response/partial response (9.72±1.11 vs 3.06±0.22, t=9.144, P<0.001). Conclusion: MiR-138 promoted CAM-DR phenotype through cell adhesion-mediated SGTA down-regulation and cell cycle arrest.

Detection and prenatal diagnosis of TOR1A gene mutation in a Chinese family affected with dystonia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the feasibility of using PCR-based capillary electrophoresis method to analysis mutation of the TOR1A gene in a family affected with primary torsion dystonia (PTD).</p><p><b>METHODS</b>Peripheral blood sample was collected from proband and amnionic fluid from her fetus for the extraction of DNA. The 5th exon of the TOR1A gene and its flanking sequences were amplified with PCR and analyzed with agarose electrophoresis, fluorescence labeled fragment analysis and Sanger sequencing.</p><p><b>RESULTS</b>Fluorescence labeled fragment analysis was performed through capillary electrophoresis, which showed that the proband carried a c.907_909delGAG (p.Glu303del) deletional mutation of the TOR1A gene. The result was verified by Sanger sequencing. The fetus DNA was also found with the same mutation by capillary electrophoresis, inferring that the fetus was probably affected with the disease.</p><p><b>CONCLUSION</b>The mutation of c.907_909delGAG of the TOR1A gene was speculated as pathologic cause of proband in this family. Fragment analysis by capillary electrophoresis combined with DNA sequencing is an efficient test for small deletional mutations and feasible for its prenatal diagnosis.</p>