Sinomenine inhibits primary CD4+ T-cell proliferation via apoptosis

Sinomenine is an active component isolated from Sinomenium acutum and is widely used as an immunosuppressive drug for treating autoimmune diseases. CD4(+) T-cell population plays a key role in adaptive immune response and is related to some autoimmune diseases. In this study, we investigated the possible immunosuppressive effect of sinomenine on CD4(+) T cells and its underlying mechanism. Our data demonstrated that sinomenine remarkably suppressed the proliferation of CD4(+) T cells, blocked the cell cycle progression from G0/G1 phase to S plusG2/M phases. Finally, the immunosuppressive activity elicited by sinomenine in CD4(+) primary lymphocytes was found to be largely accounted for by caspase 3-dependent cells apoptosis. Sinomenine did not significantly alter the expression of bcl-2 in activated CD4(+) primary T cells, suggesting that bcl-2 might not be involved in sinomenine-induced T cells apoptosis. In sum, this study proposes a novel mechanism for the immunosuppressive function of sinomenine on primary mouse CD4(+) T cells.     

Cytogenetic studies on two F1 hybrids of autotetraploid rice varieties showing extremely high level of heterosis

Mechanisms of two F1 hybrids (D46A × DTP-4 and D46A × Dminghui63) of autotetraploid rice (2n = 4x = 48) showing extremely high pollen fertility 87.40% and 85.97%, respectively, seed set 82.00% and 79.00%, respectively and extremely high level of heterosis were analyzed cytologically. The chromosome pairing of D46A × DTP-4 and D46A × Dminghui63 was normal at metaphase I(MI), and had almost no I or III, with an average of 0.020I +14.36 II 6.44rod+7.91ring) +0.01III + 4.80 IV + 0.01VIII and 0.06 I + 17.67 II (11.01rod + 6.67ring)] + 0.06 III +3.10IV+0.01VI, respectively. The most frequent chromosome configurations were 10II+7IV and 12II+bIV. The bivalent frequency was less frequent in hybrids than that in restoring parents, and the same results were gained from univalents, trivalent and multivalents. However, the quadrivalent frequency was significantly higher in hybrids than that in restoring parents at MI. The other meiotic phases progressed normally, except for low percentages of PMCs with lagging chromosomes at AI and low percentages of PMCs with micronuclei at telophaseI (TI) and telophaseII (TII). PMCs with lagging chromosomes at AI and PMCs with micronuclei at TI and TII showed negative correlation between pollen fertility and seed set. Above 90% of the PMCs could form normal microspores, which resulted in the production of viable pollen grains, abnormal microspores were observed including penta-fission and hexa-fission. Based on these results we suggest that the two F1 hybrids had better behaviors of chromosome pairing and genetic stability than autotetraploid rice and other autotetraploid plants ever studied.     

Domain selection combined with improved cloning strategy for high throughput expression of higher eukaryotic proteins

Background  

Expression of higher eukaryotic genes as soluble, stable recombinant proteins is still a bottleneck step in biochemical and structural studies of novel proteins today. Correct identification of stable domains/fragments within the open reading frame (ORF), combined with proper cloning strategies, can greatly enhance the success rate when higher eukaryotic proteins are expressed as these domains/fragments. Furthermore, a HTP cloning pipeline incorporated with bioinformatics domain/fragment selection methods will be beneficial to studies of structure and function genomics/proteomics.     

Y-like retinal ganglion cells innervate the dorsal raphe nucleus in the Mongolian gerbil (Meriones unguiculatus)

Background

The dorsal raphe nucleus (DRN) of the mesencephalon is a complex multi-functional and multi-transmitter nucleus involved in a wide range of behavioral and physiological processes. The DRN receives a direct input from the retina. However little is known regarding the type of retinal ganglion cell (RGC) that innervates the DRN. We examined morphological characteristics and physiological properties of these DRN projecting ganglion cells.

Methodology/Principal Findings

The Mongolian gerbils are highly visual rodents with a diurnal/crepuscular activity rhythm. It has been widely used as experimental animals of various studies including seasonal affective disorders and depression. Young adult gerbils were used in the present study. DRN-projecting RGCs were identified following retrograde tracer injection into the DRN, characterized physiologically by extracellular recording and morphologically after intracellular filling. The result shows that DRN-projecting RGCs exhibit morphological characteristics typical of alpha RGCs and physiological response properties of Y-cells. Melanopsin was not detected in these RGCs and they show no evidence of intrinsic photosensitivity.

Conclusions/Significance

These findings suggest that RGCs with alpha-like morphology and Y-like physiology appear to perform a non-imaging forming function and thus may participate in the modulation of DRN activity which includes regulation of sleep and mood.     

Expression of soluble, biologically active recombinant human endostatin in Escherichia coli

Endostatin, a 20kDa C-terminal fragment of collagen XVIII, is a potent anti-angiogenic protein and inhibitor of tumor growth. Recombinant endostatin was prepared from Escherichia coli deposited as insoluble, inactive inclusion bodies. In the present study, we produced soluble and biologically active recombinant human endostatin (rhEndostatin) in E. coli by employing both co-expression of the molecular chaperones and lower temperature fermentation. Two groups of chaperones Trigger factor and GroEL-GroES (GroEL/ES), DnaK-DnaJ-GrpE and GroEL/ES, were co-expressed, respectively, with rhEndostatin at different temperatures (37, 25, and 16 degrees C). It revealed that low temperature or molecular chaperones alone could enhance the production of active rhEndostatin; meanwhile, combinational employment of low temperature cultivation (16 degrees C) together with co-expression of DnaK-DnaJ-GrpE and GroEL/ES was more effective to prevent aggregation of rhEndostatin. The production of soluble rhEndostatin was about 36 mg/L, and at least 16 mg of rhEndostatin was purified from 1L flask culture. The purified rhEndostatin specifically inhibited the proliferation of endothelial cell-bovine capillary endothelial cell in a dose-dependent manner, and it showed potent anti-angiogenic capability on the chorioallantoic membrane of chick embryo in vivo. Our study provides a feasible and convenient approach to produce soluble and biologically active rhEndostatin.     

Sequence variants in the melatonin-related receptor gene (GPR50) associate with circulating triglyceride and HDL levels

The gene encoding the melatonin-related receptor (GPR50) is highly expressed within hypothalamic nuclei concerned with the control of body weight and metabolism. We screened GPR50 for mutations in an obese cohort and identified an insertion of four amino acid residues (TTGH) at position 501, two common coding polymorphisms (T528A and V602I), and one noncoding polymorphism (C-16X2GPR50T). Single-nucleotide polymorphisms were then typed in 500 English Caucasian subjects, and associations were sought to intermediate obesity phenotypes. Although no association was seen with body mass index, carriers of two copies of the mutant allele at C-16X2GPR50T, Ins501Del, and A1582G had significantly higher fasting circulating triglyceride levels (P < 0.05). In a separate set of 585 subjects, the associations were replicated, with statistically significant effects of similar magnitude and direction. The association of C-16X2GPR50T with fasting triglycerides was highly significant (P < 0.001). In addition, a significant association between C-16X2GPR50T and circulating HDL levels was observed in the combined population, with C-16X2GPR50T carriers having significantly lower circulating HDL-cholesterol levels (1.39 mM) than wild-type subjects (1.47 mM) (P < 0.01). These findings suggest a previously unexpected role for this orphan receptor in the regulation of lipid metabolism that warrants further investigation.     

Foraminiferal assemblages and the confinement index as tools for assessment of saline intrusion and human impact in the Mekong Delta and neighbouring areas (Vietnam)

Foraminiferal assemblages have been studied in 33 samples from the Can Gio region to the north of the Mekong Delta and from two regions of the Delta: the Tra Vinh province, in the middle part of the Delta; and the Ca Mau peninsula, to the south. Two plates, including 117 pictures, illustrate the species. These assemblages, either through the nature of the test or through the calculation of the confinement index Ic, clearly indicate differences in the balance between continental and marine influences, the Tra Vinh province being subject to the strongest freshwater influence. The decrease of calcareous specimens and the increase of Ic indicate the impact of deforestation in the Ca Mau peninsula, the influence of organic matter in shrimp ponds, and the impact of pollution in a tidal channel. The distribution of foraminiferal assemblages described in this study should be used as part of a reference point for further observations with a view to assessing environmental impacts of increasing human activities and/or global change.