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941.
942.
943.
Long Long Yan Huang Hao Wu Wenkang Luan Qi Zhang Hai Wen Tao Ding Youhua Wang 《Cellular and molecular neurobiology》2013,33(5):689-698
As a novel cell cycle inhibitor, PHB2 controls the G1/S transition in cycling cells in a complex manner. Its aberrant expression is closely related to cell carcinogenesis. While its expression and role in peripheral nervous system lesion and repair were still unknown. Here, we performed an acute sciatic nerve crush (SNC) model in adult rats to examine the dynamic changes of PHB2. Temporally, PHB2 expression was sharply decreased after sciatic nerve crush and reached a valley at day 5. Spatially, PHB2 was widely expressed in the normal sciatic nerve including axons and Schwann cells. While after injury, PHB2 expression decreased predominantly in Schwann cells. The alteration was due to the decreased expression of PHB2 in Schwann cells after SNC. PHB2 expression correlated closely with Schwann cells proliferation in sciatic nerve post injury. Furthermore, PHB2 largely localized with GAP43 in axons in the crushed segment. Collectively, we suggested that PHB2 participated in the pathological process response to sciatic nerve injury and may be associated with Schwann cells proliferation and axons regeneration. 相似文献
944.
Jin Zhao Jianteng Wei Ming Liu Lin Xiao Ning Wu Ge Liu Haijuan Huang Yuyan Zhang Lanhong Zheng Xiukun Lin 《Biochimie》2013
Previous study in our laboratory confirmed that a novel polypeptide, CS5931 derived from Ciona savignyi possesses potent antitumor activity. In the present study, the full length cDNA of CS5931 precursor, termed Cs-pgrn-1 was cloned. The complete cDNA sequence of this gene consists of 685 bp containing an open reading frame (ORF) of 522 bp (173 amino acid residues). In silico analysis revealed that the polypeptide consists of two identical domains, similar with granulin (GRN) found in other species, and each of the domain encodes a polypeptide identical with CS5931. Phylogenetic analysis confirmed that CS5931 shares high homology with Ciona intestinalis GRN and is conserved during evolution. The polypeptide also shows high similarity with human GRN A, B, and C. Prediction of 3D protein structure revealed the 3D structure of CS5931 is very similar with human GRN A. The CS5931 was expressed using a prokaryotic expression system and the purified polypeptide inhibited the growth of several tumor cell lines in vitro via apoptotic pathway. Our study revealed that CS5931 has the potential to be developed as a novel antitumor agent. 相似文献
945.
Jiahn-Haur Liao Yu-Huan Sun Chun-Hua Hsu Yu-Ching Lin Shih-Hsiung Wu Chao-Jen Kuo Chun-Hao Huang Shyh-Horng Chiou 《Biochimie》2013
It is generally accepted that most gastrointestinal diseases are probably caused by the bacterial pathogen Helicobacter pylori (H. pylori). In this study we have focused on the comparison of protein expression profiles of H. pylori grown under normal and high-salt conditions by a proteomics approach. We have identified about 190 proteins whose expression levels changed after growth at high salt concentration. Among these proteins, neutrophil-activating protein (NapA) was found to be consistently up-regulated under osmotic stress brought by high salts. We have investigated the effect of high salt on secondary and tertiary structures of NapA by circular dichroism spectroscopy followed by analytical ultracentrifugation to monitor the change of quaternary structure of recombinant NapA with increasing salt concentration. The loss of iron-binding activity of NapA coupled with noticeable energetic variation in protein association of NapA as revealed by isothermal titration calorimetry was found under high salt condition. The phylogenetic tree analysis based on sequence comparison of 16 protein sequences encompassing NapA proteins and ferritin of H. pylori and other prokaryotic organisms pointed to the fact that all H. pylori NapA proteins of human origin are more homologous to NapA of Helicobacter genus than to other bacterial NapA. Based on computer modeling, NapA proteins from H. pylori of human isolates are found more similar to ferritin from H. pylori than to NapA from other species of bacteria. Taken together, these results suggested that divergent evolution of NapA and ferritin possessing dissimilar and diverse sequences follows a path distinct from that of convergent evolution of NapA and ferritin with similar dual functionality of iron-binding and ferroxidase activities. 相似文献
946.
Peng Zhang Yuqiong Wu Qinggang Dai Bing Fang Lingyong Jiang 《Molecular and cellular biochemistry》2013,373(1-2):19-28
Quercetin has been reported to protect testicular cells from oxidative damage induced by environmental chemicals. In this study, we isolated interstitial Leydig cells (ILCs) from immature rats, set-up ILCs culture, co-treated cells with atrazine (ATZ) and quercetin (QT), evaluated toxicity, and measured the expression levels of antioxidant enzymes and nuclear factor-kappaB (NF-κB) and levels of steroidogenic enzymes. ATZ decreased ILCs viability at concentrations higher than 10 μg/mL and increased reactive oxygen species, malondialdehyde (MDA), and glutathione levels. ATZ also increased glutathione peroxidase, glutathione reductase, and glutathione-S-transferase and decreased superoxide dismutase-1 (sod1) and superoxide dismutase-2 (sod2) messenger RNA (mRNA) levels which were prevented by QT. The changes in the MDA levels and lactate dehydrogenase leakage induced by ATZ (50 μg/mL) were also prevented on co-treatment with QT (50 μM). Furthermore, ATZ-induced 3β- and 17β-hydroxysteroid dehydrogenase activities and NF-κB-expressions at the mRNA and protein levels were also recovered to control value on co-treatment with QT. These data showed that QT protected against ATZ-induced ILCs toxicity by restoring the expression of NF-κB and steroidogenic activity and by preventing the oxidative stress. 相似文献
947.
Qiulin Wu Lixia Gou Shuangjun Lin Jingdan Liang Jun Yin Xiufen Zhou Linquan Bai Derong An Zixin Deng Zhijun Wang 《Biochimie》2013
Calcimycin is a rare divalent cation specific ionophore antibiotic that has many biochemical and pharmaceutical applications. We have recently cloned and sequenced the Streptomyces chartreusis calcimycin biosynthesis gene cluster as well as identified the genes required for the synthesis of the polyketide backbone of calcimycin. Additional modifying or decorating enzymes are required to convert the polyketide backbone into the biologically active calcimycin. Using targeted mutagenesis of Streptomyces we were able to show that calM from the calcimycin biosynthesis gene cluster is required for calcimycin production. Inactivating calM by PCR targeting, caused high level accumulation of N-demethyl calcimycin. CalM in the presence of S-adenosyl-L-methionine converted N-demethyl calcimycin to calcimycin in vitro. The enzyme was determined to have a kinetic parameter of Km 276 μM, kcat 1.26 min−1 and kcat/Km 76.2 M−1 s−1. These results proved that CalM is a N-methyltransferase that is required for calcimycin biosynthesis, and they set the stage for generating much desired novel calcimycin derivatives by rational genetic and chemical engineering. 相似文献
948.
Wang Xinhong Liu Weimin Wu Yue Liu Xiaojun Liang Xiao Wan Zhaofei Wang Nanping Yuan Zuyi 《Molecular and cellular biochemistry》2013,377(1-2):131-141
Glycodelin A (GdA) is a dimeric glycoprotein synthesized by the human endometrium under progesterone regulation. Based on the high sequence similarity with β-lactoglobulin, it is placed under the lipocalin superfamily. The protein is one of the local immunomodulators present at the feto-maternal interface which affects both the innate as well as the acquired arms of the immune system, thereby bringing about successful establishment and progression of pregnancy. Our previous studies revealed that the domain responsible for the immunosuppressive activity of glycodelin lies on its protein backbone and the glycans modulate the same. This study attempts to further delineate the apoptosis inducing region of GdA. Our results demonstrate that the stretch of amino acid sequence between Met24 to Leu105 is necessary and sufficient to inhibit proliferation of T cells and induce apoptosis in them. Further, within this region the key residues involved in harboring the activity were shown to be present between Asp52 and Ser65. 相似文献
949.
950.
Li Guo Yang Zhao Sheng Yang Min Cai Qian Wu Feng Chen 《Molecular biology reports》2013,40(3):2175-2186
Dysregulation in the expression of miRNAs contributes to the occurrence and development of many human cancers. We herein attempted to obtain the potential association between miRNA expression profile and breast cancer by applying high-throughput sequencing technology. Small RNAs from seven paired tumor and adjacent normal tissue samples were sequenced. To determine the miRNA expression profiles in tissues and sera, another five equally pooled serum samples from 20 patients and 30 normal women were sequenced. Despite a similar number in abundantly expressed miRNAs across samples, we detected varying miRNA expression profiles. Some miRNAs showed inconsistent or opposite dysregulation trends across different tumor tissues, including some abundantly expressed miRNA gene clusters and gene families. Wilcoxon sign-rank test for paired samples analysis revealed that abnormal miRNAs showed a higher level of variation across the seven tumor samples. We also completely surveyed abnormal miRNAs expressed in tumor and serum tissues in the mixed datasets based on the relative expression levels. Most of these miRNAs were significantly down-regulated in tumor samples, but nine abnormal miRNAs (miR-18a, 19a, 20a, 30a, 103b, 126, 126*, 192, 1287) were consistently expressed in tumor tissues and serum samples. Based on experimentally validated target mRNAs, functional enrichment analysis indicated that these abnormal miRNAs and miRNA groups (miRNA gene clusters and gene families) have important roles in multiple biological processes. Dynamic miRNA expression profiles, various abnormal miRNA profiles and complexity of the miRNA regulatory network reveal that the miRNA expression profile is a potential biomarker for classifying or detecting human disease. 相似文献