Abstract:The cellular energy derives mainly from glycolysis and mitochondrial oxidation, and cellular activity correlates closely with energy status. Cancer cells have much higher rate of glucose uptake and increased glycolysis, produce high levels of lactate. Current advances in bioenergy metabolic mechanism of cancer were expounded. With intense investigation in this field combined development of metabolic imaging techniques, it will benefit unveiling the causal relationship between metabolic alteration and progress of cancer and be harnessed therapeutically.

Abstract:How the proteins are recognized and selectively degraded in the cellular life process is an important scientific question. The general mode of selective degradation of proteins in the cell in ATP- and ubiquitin-dependent pathway has been well studied. However, little attention has been directed toward the possible involvement of the proteasome in ubiquitin-independent proteolysis. In the past few years, many publications have provided evidence that the proteasome can degrade some proteins in a ubiquitin-independent manner. This pathway is involved in the elimination of some short-life regulated proteins, misfolded proteins, aged proteins and oxidized proteins as well as "quality control" of newly synthesized proteins, and involved in pathological processes such as cancer and neurodegenerative diseases. Therefore, it plays important roles in physiology and pathology. Some representative proteins degraded by the proteasome in a ubiquitin-independent manner in the past decade or two were summarized with focuses on their molecular mechanisms and the selected cases as examples to provide an overview of the field.

Abstract:Electromagnetic radiations affect human health seriously. Bio-effects of electromagnetic fields mechanisms closely depend on the properties of themselves. Moreover, electromagnetic properties of signaling molecules, radicals and magnetic particles within body will be changed in electromagnetic fields, especially the conductivity, dielectric and magnetic properties of biological tissues will be significant difference when biological tissues exposure to various frequency electromagnetic fields. Identifying the evolution of electromagnetic properties of biological tissues is a key issue to explore underlying mechanisms and prevent electromagnetic bio-effects. Effects and applications of biological tissues in electromagnetic fields are summarized, and several future research directions are put forward.

Abstract:DNA methylation regulates chromatin structure and function, playing key roles during development and in diseases. Since Tahiliani et al. identified TET1 as the first hydroxylase of 5mC in 2009, DNA hydroxymethylation, an important regulating way for DNA methylation, has become the hotspot of epigenetics. Here, the recent research progress of DNA hydroxymethylation in mouse embryonic stem cells was summarized.

Abstract:The investigated influence of long-term increases and decreases in incisal chewing stimulation on anxiety and cognition were investigated in young adult mice, and the underlying mechanisms were explored in detail. The results indicated that chewing was not associated with any significant differences in body weight, morphological differences in the mandibular and masseter muscle fibers, or the morphology of the cortex and hippocampus. In the open field test and elevated plus maze, less anxiety-related behaviors and higher activity levels were observed in the increase group; lower activity levels were observed in the decrease group. In novel object recognition, there were no significant differences in short-term memory ability between the three groups. In the Morris water maze, mice in the increase group exhibited greater spatial cognitive ability than the decrease group. To explore the mechanisms underlying the observed anxiety changes, the epinephrine (E), norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5-HT) neurotransmitters in the cortex and hippocampus were detected using high performance liquid chromatography. The results revealed that the decrease group exhibited higher NE in the cortex compared to the control and increase groups. The mRNA expression of four genes closely related with cognition (SynapsinⅠ, NR2B, CREB and BDNF) were detected using real-time quantitative PCR, to investigate the mechanisms underlying cognitive changes. The results revealed that the decrease group exhibited lower mRNA expression of cognition-related genes in the cortex and the hippocampus, while the increase group exhibited higher mRNA expression in the hippocampus. Overall, the current findings indicate that long-term incisal chewing stimulation enhancement in young adult mice may decrease anxiety-related behavior and increase activity levels and spatial cognition.

Abstract:The motile behavior of dendritic filopodia is a way by which neurons explore extracellular environment and could serve to connect dendrites with axons forming early synapses. It is unclear whether activity of astrocyte affects the motility of neuronal filopodia. To explore this possibility, astrocytes were transfected with channelrhodopsin-2 in a neuron-astrocyte mix culture model first. Expressing on cytoplasic membrane, channelrhodopsin-2 was activated by pulses of blue light and caused activation of astrocyte, in which different dynamic patterns of Ca²⁺ current were shown after the stimulation. Activated astrocytes have an inhibitory effect on filopodia motility similar to extracellularly administrated ATP and glutamate. This indicates that activated astrocytes could probably inhibit dendritic filopodia motility through releasing ATP or glutamate. A method of selectively activating astrocytes in the mix culture of neuron and astrocyte was established, which provides a novel way for studying astrocytic signal regulation of neuronal development.

Abstract:Myofibrillogenesis regulator1 (MR1) was first identified from a human skeletal muscle cDNA library in the laboratory, and the previous studies have proved the role of MR1 in Angiotensin Ⅱ(AngⅡ) -induced cardiac hypertrophy both in vivo and in vitro. However, relevant underlying molecular mechanisms of MR1 in AngⅡ induced cardiac hypertrophy remain to be elucidated. Gene silencing of MR1 by adenovirus-delivered siRNA approach in mice was used, and microarray analysis of myocardial gene expressions was compared before and after MR1 silencing along with AngⅡ treatment. Significant changes of genes expression in several pathways, such as pathways involved in cardiac hypertrophy and mTOR signaling etc., were observed between the two groups. Furthermore, genes that were changed by 10 folds after MR1 silencing were totally listed, with 39 genes being down-regulated and 5 up-regulated. To further verify the microarray results, some of genes that are suggested to be closely related to cardiac hypertrophy were detected by quantitative RT-PCR. As a result, HSP72 and thioredoxin 1 (Trx1) expression were increased, while the calcineurin Phosphatase β(CnAβ) and β-myosin (β-myosin) expression were suppressed upon MR1 silencing. These signaling pathways and genes are closely correlated with cardiac hypertrophy induced by Ang Ⅱ. The alterations of relevant pathways and genes may help understand the molecular role of MR1 in AngⅡ-induced cardiac hypertrophy.

Abstract:As a specific functional organization of genes in prokaryotic genomes, operon contains a set of adjacent genes under the control of the corresponding regulatory signals, and is expressed as the transcript unit. It has been found that genes in an operon usually tend to have related functions, or belong to the same pathway in cell. Therefore the study of operon structure is significant to understand the gene functions and regulatory networks for prokaryotes. However with the current limitation of data acquisition of operons verified by experiments such as prokaryotic transcriptomics, computation methods to annotate the operons in a newly sequenced genome have so far been the major source of operon data, and will continue to be an important mission. Over the past decade, a set of computational approaches to operon prediction have been proposed, however mainly based on experimental operons as their training sets. Nevertheless the lack of experimental operon dataset has been the bottleneck of operon prediction. The authors employ an iterative self-learning algorithm which is independent of training set with known operon dataset. The algorithm develops based on a probabilistic model using features including gene distance, regulation signals of gene expression and functional annotation such as COG. The test result compared against the experimental operon data indicates that the algorithm can reach the best accuracy without any training set. Besides, this self-learning algorithm is superior to the algorithm trained on any species with known operons. Accordingly, the algorithm can be applied to any newly sequenced genome. Moreover, comparative analysis of bacteria and archaea enhances the knowledge of universal and genome specific features of operons.

Abstract:Chloroplast is the critical organelle for transforming light energy into chemical energy in plant. At present the whole genome sequences of chloroplast of many plants have been released and the knowledge about biological processes in chloroplast has been accumulated. However, limited information regarding the expression of chloroplast-encoded proteins is available. Fifteen chloroplast genes were selected from chloroplast-encoded proteins and the expression profiling in different stages of rice leaves were investigated by Western blotting. The results indicated that the expression patterns of 7 photosynthesis-related proteins are similar and the expression level increase steadily as leaves grow taller. Until the booting and flowering stages, the expression reached the highest-level, and then decreased at filling stage. The correlation between the expression of photosynthesis-related proteins and the photosynthesis was observed. The expression levels of 4 RNA polymerase related to DNA replication were at their highest-level at seedling stage, which indicated that they perform their functions during the early stage. However, 4 NADH dehydrogenase exhibited two kinds of expression patterns. Subunit-2 and -4 reached their highest-level when the leaves were 1cm in length during seedling stage. While, subunit-5 and -7 reached theirs in middle and later stage of seedling. The results implied their different functions during seedling stages. Taking together, this experiment revealed the expression patterns of rice chloroplast-encoded proteins in rice leaves at different growth stages and the correlation between the proteins and the growing process in a direct and relative quantitative way, and provided significant information for further research of their function.

Abstract:It is well known that the gene expression profiling can be detected by RT-PCR singly, or which can be detected by cDNA array in large numbers, however, to evaluate the expression of several targeted genes in a special regulation pathway, or some interested genes in a certain disease simultaneously, the methods were limited. So, development of a simple, robust, sensitive, specific and economic assay satisfied the need mentioned above was very useful, and a bead-based flow-cytometric multiplex assay was aimed to establish. Multiplex ligation-dependent probe amplification (MLPA) was employed to amplify several targeted cDNAs using only one pair identical primers, each MLPA probe consisted of two short synthetic oligonucleotides, and the tag which was coupled chemically to the fluorescent beads was complementary to one probe. Five beads with different fluorescence intensity coupled to RAC2, RhoBTB3, SPA-1, Rap1GAP and GAPDH were established. Biotinylated PCR amplicons were then hybridized to the complementary tag on each bead set. Bound amplicons were detected by flow cytometry using a streptavidin-linked reporter dye, PE. 111 BM specimens were analyzed in total, include RA(22), RAEB(22), RAEBt(9), AML(33), and control group (22, including hyperplastic anemia, iron deficiency anemia, aplastic anemia et al), and the difference of the transcriptional level of RAC2, RhoBTB3, SPA-1 and Rap1GAP relative to GAPDH were analyzed using wilcoxon non-parametric test and SNK method among different groups. The results were confirmed by RQ-PCR. The bead-based flow-cytometric array had an excellent sensitivity and a wide linear range, could get a positive signal for PCR product from 0.002 5 to 0.1 μmol, the fine specificity was proved by no cross-hybridization signals presented among different bead set, and the reproducibility were also good enough(P < 0.001). The expression profiling of RAC2, RhoBTB3, SPA-1, Rap1GAP and GAPDH detected by this liquid bead-based flow-cytometric array were obtained, and there existed significant difference among 5 groups ( MDS-RA, -RAEB, -RAEBt, AML, and control group )for the relative expression to GAPDH of RAC2, RhoBTB3, SPA-1 and Rap1GAP (P < 0.0001, P = 0.049 1, P = 0.020 6 and P = 0.004 6 respectively). These results were validated by RQ-PCR, and the data obtained by each method had close linear correlation, the Pearson correlation coefficient was 0.930, 0.946, 0.945 and 0.921 for RAC2, RhoBTB3, SPA-1 and Rap1GAP respectively(P < 0.001 for all four). A bead-based flow-cytometric multiplex assay for rapid assessment of gene expression profiling has been built successfully, and it was validated by RQ-PCR.

Abstract:To simultaneously detecting the C-peptide and insulin in human serum, a dual-labeling time-resolved fluoroimmunoassay(TRFIA) for detection of C-peptide and insulin was preliminary founded. Two capture monoclonal antibodies were mixed together and then coated in human serum. Two counterpart tracer monoclonal antibodies, were labeled with Eu³⁺ (anti-Insulin) and Sm³⁺ (anti-C-peptide) chelates, respectively. The double antibody sandwich in one step method was used to develop the TRFIA for simultaneously detection of the C-peptide and insulin in human serum. These results showed that sensitivity of C peptide analysis was up to 0.2 μg/L, linear range is 0.5～22 μg/L, the recovery percent is 99.6%, The intra- and inter-assay coefficient of variation were 4.6%～6.0% and 5.1%～7.6%, respectively; sensitivity of insulin analysis was up to 0.8 mU/L, linear range is 3.6～180 mU/L, the recovery percent is 99.4%, the intra- and inter-assay coefficient of variation were 3.7%～6.0% and 5.1%～8.0%, respectively. Moreover, 200 samples were tested by the self-made and commercially available C-peptide and insulin kit (PerkinElmer) kits at the same time. The correlation coefficient was 0.98 and 0.99, respectively. In conclusion, the self-made dual-labeling time-resolved fluoroimmunoassay for simultaneously detection of C-peptide and insulin might be a simple, sensitive and rapid method for rapid diagnosis for the diabetes caused by the lack of insulin secretion, it would also provide an alternative route for serology high-screening of the samples for C-peptide and insulin in clinical application.