GsCML27, a Gene Encoding a Calcium-Binding Ef-Hand Protein from Glycine soja,Plays Differential Roles in Plant Responses to Bicarbonate,Salt and Osmotic Stresses

Calcium, as the most widely accepted messenger, plays an important role in plant stress responses through calcium-dependent signaling pathways. The calmodulin-like family genes (CMLs) encode Ca²⁺ sensors and function in signaling transduction in response to environmental stimuli. However, until now, the function of plant CML proteins, especially soybean CMLs, is largely unknown. Here, we isolated a Glycine soja CML protein GsCML27, with four conserved EF-hands domains, and identified it as a calcium-binding protein through far-UV CD spectroscopy. We further found that expression of GsCML27 was induced by bicarbonate, salt and osmotic stresses. Interestingly, ectopic expression of GsCML27 in Arabidopsis enhanced plant tolerance to bicarbonate stress, but decreased the salt and osmotic tolerance during the seed germination and early growth stages. Furthermore, we found that ectopic expression of GsCML27 decreases salt tolerance through modifying both the cellular ionic (Na⁺, K⁺) content and the osmotic stress regulation. GsCML27 ectopic expression also decreased the expression levels of osmotic stress-responsive genes. Moreover, we also showed that GsCML27 localized in the whole cell, including cytoplasm, plasma membrane and nucleus in Arabidopsis protoplasts and onion epidermal cells, and displayed high expression in roots and embryos. Together, these data present evidence that GsCML27 as a Ca²⁺-binding EF-hand protein plays a role in plant responses to bicarbonate, salt and osmotic stresses.     

Embigin/basigin subgroup of the immunoglobulin superfamily: Different modes of expression during mouse embryogenesis and correlated expression with carbohydrate antigenic markers

Embigin and basigin are highly glycosylated transmembrane glycoproteins with two immunoglobulin domains and form a subgroup in the immunoglobulin superfamily. Previous studies have demonstrated the functional significance of these molecules. In the present study, in situ hybridization analysis of their expression was performed during mouse embryogenesis. Embigin was strongly expressed in the endoderm during early postimplantation embryogenesis, and in the somite stage in the gut and visceral endoderm. Embryonic ectoderm and its derivative tissues weakly to moderately expressed this molecule. From day 10 to 15 of gestation, no embigin signal was detected. Basigin was more broadly expressed. During the organogenesis period, basigin was expressed in various epithelial tissues, brain ventricles, the spinal cord and dorsal root ganglion. The modes of expression of these two proteins throughout the egg cylinder stage correlated with the expression of the carbohydrate markers that they carry; embigin with Dolichos biflorus agglutinin binding sites and basigin with Le^x antigen and more closely with fucosyltransferase IV, which forms the antigenic epitope. These findings imply that proteins with specific carbohydrate epitopes play roles in early postimplantation embryogenesis.     

Identification,Expression and Activity Analyses of Five Novel Duck Beta-Defensins

In the current study, five novel avian β-defensins (AvBDs) were identified and characterized in tissues from Peking ducks (Anas platyrhynchos). The nucleotide sequences of these cDNAs comprised 198 bp, 182 bp, 201 bp, 204 bp, and 168 bp, and encoded 65, 60, 66, 67, and 55 amino acids, respectively. Homology, characterization and comparison of these genes with AvBD from other avian species confirmed that they were Apl_AvBD1, 3, 5, 6, and 16. Recombinant AvBDs were produced and purified by expressing these genes in Escherichia coli. In addition, peptides were synthesized according to the respective AvBD sequences. Investigation of the antibacterial activity of the Apl_AvBDs showed that all of them exhibited antibacterial activity against all 12 bacteria investigated (P<0.05 or P<0.01). In addition, the antibacterial activity of all of the AvBDs against M. tetragenus and P. multocida decreased significantly in the presence of 150 mM NaCl (P<0.01). None of the AvBDs showed hemolytic activity. Consistent with their broad-spectrum antibacterial activity, the five novel Apl_AvBDs inhibited replication of duck hepatitis virus (DHV) in vitro significantly (P<0.05). The mRNA expression of all five Apl_AvBD in most tissues, including immune organs and the liver, was upregulated in response to DHV infection at different time points. These findings provide evidence that these defensins activate the immune response to combat microbial infection.     

A Potent Anti-HB-EGF Monoclonal Antibody Inhibits Cancer Cell Proliferation and Multiple Angiogenic Activities of HB-EGF

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a member of the epidermal growth factor family and has a variety of physiological and pathological functions. Modulation of HB-EGF activity might have a therapeutic potential in the oncology area. We explored the therapeutic possibilities by characterizing the in vitro biological activity of anti-HB-EGF monoclonal antibody Y-142. EGF receptor (EGFR) ligand and species specificities of Y-142 were tested. Neutralizing activities of Y-142 against HB-EGF were evaluated in EGFR and ERBB4 signaling. Biological activities of Y-142 were assessed in cancer cell proliferation and angiogenesis assays and compared with the anti-EGFR antibody cetuximab, the HB-EGF inhibitor CRM197, and the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab. The binding epitope was determined with alanine scanning. Y-142 recognized HB-EGF as well as the EGFR ligand amphiregulin, and bound specifically to human HB-EGF, but not to rodent HB-EGF. In addition, Y-142 neutralized HB-EGF-induced phosphorylation of EGFR and ERBB4, and blocked their downstream ERK1/2 and AKT signaling. We also found that Y-142 inhibited HB-EGF-induced cancer cell proliferation, endothelial cell proliferation, tube formation, and VEGF production more effectively than cetuximab and CRM197 and that Y-142 was superior to bevacizumab in the inhibition of HB-EGF-induced tube formation. Six amino acids in the EGF-like domain were identified as the Y-142 binding epitope. Among the six amino acids, the combination of F115 and Y123 determined the amphiregulin cross-reactivity and that F115 accounted for the species selectivity. Furthermore, it was suggested that the potent neutralizing activity of Y-142 was derived from its recognition of R142 and Y123 and its high affinity to HB-EGF. Y-142 has a potent HB-EGF neutralizing activity that modulates multiple biological activities of HB-EGF including cancer cell proliferation and angiogenic activities. Y-142 may have a potential to be developed into a therapeutic agent for the treatment of HB-EGF-dependent cancers.     

A helper factor needed for the generation of mouse cytolytic T lymphocytes is made by tumor cell lines, cloned T cells, and spleen cells exposed to a variety of stimuli

A helper factor termed cytolytic T lymphocyte helper factor (CHF) that is needed for the generation of allospecific mouse cytolytic T lymphocytes (CTL) in vitro was produced by mouse spleen cells 3 to 4 days after the time when interleukin 2 (IL 2) had reached its maximal production. These kinetics were observed by stimulation of immune spleen cells with allogeneic tumor or spleen cells, with Sendai or influenza viral peptides, with virus infected cells, or with concanavalin A (Con A). CHF produced by rat spleen cells was able to help in the generation of mouse CTL, indicating that this cytokine was not restricted genetically. CHF could also be made by WEHI-3 and EL4 cell lines, as well as cloned cytolytic and helper T cells. The production of CHF by WEHI-3 cells argues that CHF is not IL 2. In addition, if CHF was not present early in the in vitro stimulation no CTL were generated, suggesting that CHF participated in the activation of CTL precursors. The addition of IL 2-containing conditioned medium to the CHF assay resulted in no substantial CTL generation, although significant cellular proliferation was observed. In contrast, CHF-containing conditioned medium allowed the generation of CTL in the absence of the same level of proliferation.     

The fauna of anoplocephalid tapeworms in domestic and wild animals of Vietnam]

101 species of oribatid mites and 12 species of helminths--anoplocephalids, transmitted by these mites, were found out by Soviet-Vietnam studies in agroecosystems and tropical forests of northern and southern Vietnam. Helminths were recorded from graminivorous mammals as follows: horses, zebu, sheep, goats, buffaloes, deer, hares, elephant, 2 species of rates, 5 species of monkeys and 11 species of birds.     

溶瘤病毒载体研究进展

溶瘤病毒(oncolytic virus,OVs)疗法是治疗肿瘤的一种新方法,它可通过直接杀死肿瘤细胞并引起机体的免疫反应发挥作用.然而天然溶瘤病毒有一定的局限性,因此需将各种不同的病毒作为载体,通过基因修饰的方法增强或减弱病毒毒力并导入新的功能性基因,以提高其溶瘤作用.目前可以作为溶瘤病毒载体的有单纯疱疹病毒、腺病毒、牛痘病毒、水泡性口炎病毒、麻疹病毒、腮腺炎病毒、脊髓灰质炎病毒等.这些病毒载体均可通过不同的基因修饰方法,靶向性感染并杀死不同的肿瘤细胞,获得较好的溶瘤作用.本文综述了几种溶瘤病毒载体的基因修饰方法,以及修饰后的溶瘤效果.     

Single-cell landscape of the ecosystem in early-relapse hepatocellular carcinoma

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The genus Cahara Ghauri, 1978 of China (Hemiptera,Heteroptera, Pentatomidae,Halyini) with?descriptions of two new species

Cahara Ghauri from China with three species is reviewed here. Two of them, Cahara incisura sp. n. and Cahara nodula sp. n. are described here. Key to the three Chinese species, habitus photographs and illustrations of genitalia are also provided. All examined materials including the types of three species mentioned are deposited in the Institute of Entomology, Nankai University, Tianjin, China (NKUM).