中国东、南部的3个腔蚓属蚯蚓新物种

本文报道了寡毛纲(Oligochaeta)巨蚓科(Megascolecidae)腔蚓属(Metaphire)3个新发现物种,分别是象头山腔蚓(M. xiangtoumontis Dong & Jiang sp. nov.),韩摆渡腔蚓(M. hanbaiduensis Dong & Sun sp. nov.)和长白山腔蚓(M. changbaimontis Dong & Shen sp. nov.)。象头山腔蚓受精囊孔2对,位于7/8 ~ 8/9节间,属于M. insulana物种群。韩摆渡腔蚓受精囊孔3对,位于6/7 ~ 8/9节间,属于M. houlleti物种群。长白山腔蚓受精囊孔2对,位于6/7 ~ 7/8节间,属于M. glandularis物种群。所有新物种均附有形态学描述、图片、与相似物种的形态学比较及与GenBank上亲缘关系相近物种的遗传距离计算分析。以上结果丰富了我国腔蚓属蚯蚓的物种多样性,并首次记录了采集于长白山国家级自然保护区的巨蚓科蚯蚓新物种。     

The expression of a novel estrogen receptor, GPR30, in epithelial ovarian carcinoma and its correlation with MMP-9

The aim of the present study is to investigate the expression of a novel estrogen receptor, G protein-coupled receptor 30 (GPR30) and its correlation with matrix metalloproteinases-9 (MMP-9) in epithelial ovarian cancer (EOC). Ovary tissues were obtained from 39 female patients, including 30 cases of EOC and 9 cases of benign ovarian tumor. Four normal ovary tissues were used as control. Immunohistochemical staining was used to detect the expressions of GPR30 and MMP-9. Chi square test, Fisher's exact test and Spearman's rank correlation analysis were used for statistical analysis. The results showed that GPR30 overexpression rate in EOC cases was significantly higher than those in benign ovarian tumor and normal ovary cases. Whereas MMP-9 overexpression rate in EOC cases was significantly higher than that in normal ovary cases, without any difference to that in benign ovarian tumor cases. To demonstrate the relationship between GPR30 and clinicopathological variables of EOC, we further analyzed the pathology type, FIGO stage and age of patients sampled in our study. The analysis showed there were significant differences of GPR30 overexpression rate among various pathology types and different FIGO stages (P<0.05), and no significant difference of both GPR30 and MMP-9 among three age groups (P>0.05). Moreover, GPR30 expression was positively correlated with MMP-9 (r(s)=1.000, P=0.002). These results suggest that GPR30 may be involved in the invasion and metastasis of EOC, being a potential index of EOC early diagnosis and malignancy grade prediction.     

A sensitive signal-on assay for MTase activity based on methylation-responsive hairpin-capture DNA probe

This work develops a simple, sensitive and signal-on electrochemical sensor for methyltransferase (MTase) activity analysis. The sensor is composed of a methylene blue-modi?ed "signaling DNA probe" and a "capture DNA probe" tethered methylation-responsive hairpin DNA (hairpin-capture DNA probe). The thiol- modified hairpin-capture DNA probe at 5' end was firstly self-assembled on gold electrode via Au-S bonding. Methylation-induced scission of hairpin-capture DNA probe would displace the hairpin section and remain the "capture DNA probe" section on the gold electrode. Subsequently, the remained "capture DNA probe" on the gold electrode can hybridize with the methylene blue-modi?ed "signaling DNA probe", mediating methylene blue onto the gold electrode surface to generate redox current. It was eT on state. The developed facile signal-on electrochemical sensing system showed a linear response to concentration of Dam MTase range from 0.1 to 1.0 U/mL. The detection limit of Dam MTase activity was determined to be 0.07 U/mL and the total detection time is 7h. The sensor also has the ability to provide information about the dynamics of methylation process. Furthermore, we demonstrated that this sensor could be utilized to screen inhibitors or drugs for Dam MTase.     

Spindlin1, a novel nuclear protein with a role in the transformation of NIH3T3 cells

spindlin1, a novel human gene recently isolated by our laboratory, is highly homologous to mouse spindlin gene. In this study, we cloned cDNA full-length of this novel gene and send it to GenBank database as spindlin1 (Homo sapiens spindlin1) with Accession No. AF317228. In order to investigate the function of spindlin1, we studied further the subcellular localization of Spindlin1 protein and the effects of spindlin1 overexpression in NIH3T3 cells. The results showed that the fusion protein pEGFP-N1-spindlin1 was located in the nucleus and the C-terminal is correlated with nuclear localization of Spindlin1 protein. NIH3T3 cells which could stably express spindlin1 as a result of RT-PCR analysis compared with the control cells displayed a complete morphological change; made cell growth faster; and increased the percentage of cells in G2/M and S phase. Furthermore, overexpressed spindlin1 cells formed colonies in soft agar in vitro and formed tumors in nude mice. Our findings provide direct evidence that spindlin1 gene may contribute to tumorigenesis.     

Secretory delivery of heterologous proteins in attenuated <Emphasis Type="Italic">Vibrio anguillarum</Emphasis> for potential use in vaccine design

To synthesize and secrete heterologous proteins in an attenuated Vibrio anguillarum strain for potential multivalent live vaccine development, different antigen-delivery systems based on bacterial-originated secretion signal peptides (SPs) were designed and identified in this work. Four SPs were derived from hemolysin of Escherichia coli, RTX protein of V. cholerae, hemolysin of V. anguillarum, zinc-metalloprotease of V. anguillarum, respectively, and their abilities to support secretion of green fluorescent protein (GFP) in an attenuated V. anguillarum strain MVAV6203 were assayed. Immunodetection of GFP showed that the capability of the tested signal leaders to direct secretion of GFP varied greatly. Although all the four signal peptide-fused GFPs could be expressed correctly and trapped intracellularly in recombinant strains, only the EmpA signal peptide could confer efficient secretion to GFP. For the investigation of its potential application in live bacteria carrier vaccines, a heterologous protein EseB of Edwardsiella tarda was fused to the SP(empA) antigen-delivery system and introduced into the strain MVAV6203. Further analysis of EseB demonstrated that the constructed SP(empA) antigen-delivery system could be used to secrete foreign protein in attenuated V. anguillarum and be available for carrier vaccines development.     

The molecular basis of spinocerebellar ataxia type 48 caused by a de novo mutation in the ubiquitin ligase CHIP

The spinocerebellar ataxias (SCAs) are a class of incurable diseases characterized by degeneration of the cerebellum that results in movement disorder. Recently, a new heritable form of SCA, spinocerebellar ataxia type 48 (SCA48), was attributed to dominant mutations in STIP1 homology and U box-containing 1 (STUB1); however, little is known about how these mutations cause SCA48. STUB1 encodes for the protein C terminus of Hsc70 interacting protein (CHIP), an E3 ubiquitin ligase. CHIP is known to regulate proteostasis by recruiting chaperones via a N-terminal tetratricopeptide repeat domain and recruiting E2 ubiquitin-conjugating enzymes via a C-terminal U-box domain. These interactions allow CHIP to mediate the ubiquitination of chaperone-bound, misfolded proteins to promote their degradation via the proteasome. Here we have identified a novel, de novo mutation in STUB1 in a patient with SCA48 encoding for an A52G point mutation in the tetratricopeptide repeat domain of CHIP. Utilizing an array of biophysical, biochemical, and cellular assays, we demonstrate that the CHIP^A52G point mutant retains E3-ligase activity but has decreased affinity for chaperones. We further show that this mutant decreases cellular fitness in response to certain cellular stressors and induces neurodegeneration in a transgenic Caenorhabditis elegans model of SCA48. Together, our data identify the A52G mutant as a cause of SCA48 and provide molecular insight into how mutations in STUB1 cause SCA48.     

P2 pyridine N-oxide thrombin inhibitors: a novel peptidomimetic scaffold

In this study, we have demonstrated that the critical hydrogen bonding motif of the established 3-aminopyrazinone thrombin inhibitors can be effectively mimicked by a 2-aminopyridine N-oxide. As this peptidomimetic core is more resistant toward oxidative metabolism, it also overcomes the metabolic liability associated with the pyrazinones. An optimization study of the P(1) benzylamide delivered the potent thrombin inhibitor 21 (K(i) = 3.2 nM, 2xaPTT = 360 nM), which exhibited good plasma levels and half-life after oral dosing in the dog (C(max) = 2.6 microM, t(1/2) = 4.5 h).     

Studies on Some Properties of the Apoplastic β-N-Acetyl-D-Hexosaminidase from Tomato Leaves

Some properties of the β-N-acetyl-D-hexosaminidase purified from intercellular fluid of tomato leaves after the plant was systematically infected by TMV (tobacco mosaic virus) were studied. When pNP β-D-GlcNAc (p nitrophenyl-N-aeetyl β-D-glucosaminide) or pNP β-D- GalNAc (p-nitrophenyl-N-acetyl-β-D galactosaminide) was used as the substrate, it showed the optical pH between 4. 8--5.0 and optical temperature between 44— 47℃. Studies of thermostabillty indicated that the enzyme had a biphasic denaturation curve. Using pNP-β-D-GIcNAc or pNP-β-D GalNAc as the substrate, the Km value of the enzyme was 0. 36 and 0. 67 mmol/L respectively. N acetyi-D glucosamine and N acetyl-D-galactosamine were competitive inhibitors of the enzyme activities. Ag+ and Hg2+ were sensitive inhibitors and Fe2+ . Fe3+ and Cu2+ were also inhibitors enzyme activities.     

Production of ascorbic acid,total protein,callus and root in vitro of non-heading Chinese cabbage by tissue culture

Molecular Biology Reports - The objective of the present work was the selection of cultivar, suitable medium and explant type for callus, root production, ascorbic acid, total ascorbic acid,...