rbcS SRS4 promoter from Glycine max and its expression activity in transgenic tobacco

The regulatory region of the ribulose-1,5-bisphosphate carboxylase small subunit gene SRS4 from soybean (Glycine max) was cloned using TAIL-PCR and general PCR, and named the rbcS promoter. The promoter was fused with the GUS gene and introduced into Nicotiana tabacum via Agrobacterium-mediated leaf disk transformation. In 4-week-old transgenic tobacco plants, the highest GUS expression levels were observed in the leaves, GUS activity was 7.13- and 7.40-fold higher in leaves than in stems and roots, respectively. Moreover, GUS activity was stimulated by light. In conclusion, spatial and light regulation of the soybean rbcS promoter was observed in N. tabacum, thus illustrating a leaf-specific and light-induced promoter.

Effect of sample preparation on components and liver toxicity of Polygonum multiflorum

It was shown that different extracts had significant differences in the toxicity of Polygonum multiflorum. In this study, the effect of sample preparation on components and liver toxicity of different extracts from P. multiflorum were determined. Hepatoxic components were discovered based on biomembrane extraction. Comparative chemistry and toxicology between ethanol and water extracts were also performed. The results showed that ethanol extract had much stronger hepatotoxicity, the content of emodin-8-O-β-d-glucopyranoside, physcion-8-O-β-d-glucopyranoside, emodin and physcion was significantly higher in ethanol extract than in water extract, while the human hepatocytes extraction showed that 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucopyranoside, emodin-8-O-β-d-glucopyranoside, physcion-8-O-β-d-glucopyranoside, emodin and physcion had interaction with human hepatocytes. The hepatotoxic effect of these components was investigated on human hepatocytes LO2 cells and emodin-8-O-β-d-glucopyranoside, physcion-8-O-β-d-glucopyranoside, emodin and physcion were finally confirmed to be, at least partial, hepatotoxic components. The results showed that sample preparation has significant effect on components in extracts of P. multiflorum especially the components related to hepatotoxicity. Water extract, the conventional administration form of Chinese herbs, is prefer for phytotherapy before well understanding their chemistry and biological activities.

Effects of dietary supplementation with green tea polyphenols on digestion and meat quality in lambs infected with Haemonchus contortus

Ujumqin sheep are susceptible to infection by the gastrointestinal nematode Haemonchus contortus, which reduces productivity and total meat yield in sheep. Thus, the effects of green tea polyphenol (GTP) supplements (0, 2, 4, or 6g of GTP/kg feed) on dietary nutrient digestibility and meat quality in lambs infected with H. contortus were examined; control lambs were not infected. H. contortus infections did not affect digestion but the apparent digestibilities of nutrients were decreased by dietary 2g of GTP/kg feed supplementation. There was an interaction between treatment and sampling time on plasma total protein, urea nitrogen, and amino acid concentrations. The antioxidant activity and meat color of INFGTP0 lambs decreased. In conclusion, H. contortus infections in lambs decreased meat quality, but appropriate levels of dietary GTP supplementation diminished these negative effects though lower dose of GTP supplement showed negative effects on digestion.

Genome-wide identification and expression analysis of the CPP-like gene family in soybean

Cysteine-rich polycomb-like protein (CPP-like) genes are a group of transcription factors with highly conserved cysteine-rich domains and are widely distributed in animals and plants, but do not present in yeast. Previous studies have shown that members of this family play important roles in the development of reproductive tissue and in the control of cell division in plants. In this study, whole genome identification of soybean CPP transcription factors was performed using bioinformatic methods. The results showed that there were 20 CPP transcription factors in the soybean genome, which encoded for 28 distinct CPP proteins. These transcription factors were distributed on 16 of 20 chromosomes. Phylogenetic relationship analysis showed that expression of CPP gene family members occurred before the differentiation of monocotyledons and dicotyledons. RNA-Seq analysis showed that 5 genes were highly expressed in all tissues, including Glyma10g39080, Glyma01g44670, Glyma101g66920, Glyma02g01540, and Glyma20g28740. One gene (Glyma14g14750) was specifically expressed in young leaves, while 2 genes (Glyma02g01540 and Glyma10g01580) were highly expressed in root nodules. Quantitative reverse transcriptase-polymerase chain reaction analysis revealed that the expression levels of most genes increased in the roots under high temperature stress. Our findings indicate that these genes are not only involved in growth and development, but also in the responses to high temperature stress in soybean roots.

Early third trimester maternal response to glucose challenge and pregnancy outcome in Chinese women-relationship between upper distribution level and recommended diagnostic criteria

BACKGROUND/OBJECTIVES

The objective of this study was to examine the relationship between upper distribution levels of glucose values in the 75-g oral glucose tolerance test (OGTT) and recommended diagnostic criteria for gestational diabetes mellitus (GDM) and adverse pregnancy outcomes.

SUBJECTS/METHODS

The distribution of the OGTT 2-h values of 13,501 pregnant women, which were below the World Health Organization (WHO) threshold for overt diabetes mellitus (DM), and managed in one teaching hospital in China, was reviewed and related to maternal characteristics and pregnancy outcomes.

RESULTS

For the entire group, the 90th and 95th percentile values of the OGTT 2-h glucose level, respectively, were close to the diagnostic cutoff values of the WHO and International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria. For adverse maternal outcomes, glucose level above the 90th percentile value was associated with increased hypertensive disorders, whereas no difference was seen with cutoff using the 95th percentile value. For perinatal outcomes, the 90th percentile was associated with increased neonatal intensive care unit admission and hypoglycemia, whereas the 95th percentile showed in addition association with phototherapy for jaundice and 5th-minute Apgar score <7. Although no differences in the incidence of adverse pregnancy outcomes were found using the different cutoffs, the >95th percentile cutoff value would have missed out 33.3-56.7% of the cases of adverse outcomes that would otherwise have been attributed to GDM.

CONCLUSIONS

Further studies are warranted to clarify which diagnostic criterion is most appropriate universally to identify adverse pregnancy outcomes attributed to GDM, and which could be mitigated with treatment specific for GDM.

Amelioration of high fat diet-induced glucose intolerance by blockade of Smad4 in pancreatic beta-cells

BACKGROUND

In this study, we investigated whether Smad4 signaling is involved in the regulation of beta-cell function using a high fat diet (HFD)-induced obesity mouse model.

METHODS

Beta-cell-specific Smad4-knockout mice (Smad4(-/-)RIP-Cre(+); β-Smad4KO) were generated by mating Smad4 (flox/flox) mice with rat insulin promoter (RIP)-Cre mice. Mice were fed a HFD beginning at 6 weeks of age for 16 weeks. Body weight, food intake, fasting and fed glucose levels, and glucose and insulin tolerance were measured.

RESULTS

The expression of Smad4 mRNA was significantly decreased in the islets of β-Smad4KO mice. In wild-type mice, Smad4 mRNA was significantly decreased at 18 weeks of age as compared with 8 weeks of age. On a regular chow diet, β-Smad4KO mice showed no differences in body weight, fed and fasting blood glucose levels, and glucose tolerance compared with wild-type mice. When fed a HFD, body weight gain was significantly reduced in β-Smad4KO mice as compared with wild-type mice, although the amount of food intake was not different. During the HFD, fed and fasting blood glucose levels, glucose stimulated insulin secretion, disposition index and glucose tolerance were significantly improved in β-Smad4KO mice as compared with wild-type mice. However, insulin tolerance tests showed no differences between the 2 groups.

CONCLUSION

Inhibition of Smad4 in beta-cells conferred mild but significant improvements in glucose levels and glucose tolerance in HFD-induced obese mice. Therefore, regulation of Smad4 expression may be one of the mechanisms regulating physiological expansion of beta-cells during development of type 2 diabetes.

Genetic diversity in wild populations of Paulownia fortune

The genetic diversities of 16 Paulownia fortunei populations involving 143 individuals collected from 6 provinces in China were analyzed using amplified fragment length polymorphism (AFLP). A total of 9 primer pairs with 1169 polymorphic loci were screened out, and each pair possessed 132 bands on average. The percentage of polymorphic bands (98.57%), the effective number of alleles (1.2138-1.2726), Nei's genetic diversity (0.1566-0.1887), and Shannon's information index (0.2692-0.3117) indicated a plentiful genetic diversity and different among Paulownia fortunei populations. The genetic differentiation coefficient between populations was 0.2386, while the gene flow was 1.0954, and the low gene exchange promoted genetic differentiation. Analysis of variance indicated that genetic variation mainly occurred within populations (81.62% of total variation) rather than among populations (18.38%). The 16 populations were divided by unweighted pair-group method with arithmetic means (UPGMA) into 4 groups with obvious regionalism, in which the populations with close geographical locations (latitude) were clustered together.

Interaction of six candidate genes in essential hypertension

We explored the interaction of 6 candidate genetic mutations in essential hypertension (EH). The mutations AGT M235T, ACE I/D, eNOS Glu298Asp, ET-2 A985G, ANP T2238C, and NPRC A-55C were detected using a genechip microarray in 100 patients with EH and 97 controls from the Han population living in the Yunnan Province of China. Risks of EH were evaluated with respect to a combination of these genotypes. Interactions were analyzed using multifactor dimensionality reduction (MDR). P values were corrected using Bonferroni's adjustment. Results showed that CC genotype frequencies for NPRC A-55C (0.540) in EH were significantly higher than those in controls (0.237, Pc < 0.01; odds ratio (OR) = 3.777; 95% confidence interval (CI) = 2.050-6.960). The OR for NPRC A-55C CC combined with ET-2 A985G GG increased to 4.673 and to 5.529 when the MT genotype of AGT M235T, the EE genotype of eNOS Glu298Asp, the GG genotype of ET-2 A985G, and the CC genotype of NPRC A-55C were combined. MDR showed that ET-2/NPRC is the best model (OR = 4.002; 95%CI = 2.1597-7.4159). The CC genotype for NPRC A-55C and the G allele for ET-2 A985G were associated with susceptibility to EH. Although the contributions of the candidate genes differ, they may have cooperative effects on conferring risk for EH. Moreover, potential gene-gene interactions were found between ET-2 A985G and NPRC A-55C in EH.

Hypoxia and Serum deprivation protected MiaPaCa-2 cells from KAI1-induced proliferation inhibition through autophagy pathway activation in solid tumors

PURPOSE

KAI1 closely correlates with pancreatic cancer metastasis. There might be some factors that protect the cells from a proliferation inhibition by KAI1 in the solid tumors' microenvironment. Hypoxia and ischemia are the main characteristics of the microenvironment within solid tumors. Whether they affect the KAI1 inhibitory effects on cell proliferation is still unclear.

METHODS

MiaPaCa-2 human pancreatic cancer cells do not express KAI1 protein. However, after being infected with Ad5-KAI1, they expressed KAI1 protein. We cultured them under hypoxic and serum-free conditions to simulate the solid tumor hypoxic-ischemic microenvironment. The cells were divided into the control, hypoxic, serum-free, and hypoxic with serum-free groups. The proliferation and apoptosis were observed by CCK8 and Annexin V-FITC/PI, respectively. The green fluorescent protein-labeled light chain 3 association with autophagosome membranes was detected by confocal microscopy. The ratio of LC3-II-LC3-I expression level was detected by western blot. Pretreatment of 3-MA was used to inhibit the autophagy. We, then observed whether the hypoxic and serum-free conditions could change the effect of KAI1 on cell survival and whether the pretreatment of 3-MA could inhibit the effect of hypoxic and serum-free conditions on KAI1 function.

RESULTS

Hypoxia and serum-free media effectively reduced the apoptosis and proliferation inhibition caused by KAI1 and was beneficial to the cell survival. 3-MA pretreatment effectively blocked the protective effect of hypoxia and serum-free media on the cells by autophagy block.

CONCLUSIONS

Serum-free media and hypoxia protected the MiaPaCa-2 cells from a KAI1-induced apoptosis and proliferation inhibition via autophagy induction.

Genetic diversity and population structure in Harpadon nehereus based on sequence-related amplified polymorphism markers

In this study, the genetic diversity among ten populations of the Bombay duck was studied on the basis of sequence-related amplified polymorphism (SRAP). The ten populations were collected from the East China Sea and South China Sea areas. A total of 98 loci were obtained from 292 individuals using eight SRAP primers. The average proportion of polymorphic loci, genetic diversity (H), and Shannon's information index were 75.20%, 0.2478, and 0.3735, respectively. Nei's genetic distance and Shannon's information index between the ten populations ranged from 0.0410 to 0.3841 and from 0.2396 to 0.4506, and the averages Nei's gene diversity index (H = 0.2478) and Shannon's information index (I = 0.3735) at the population level were high. AMOVA showed that most of the variation was within populations (71.74%), and only 28.26% of the variation was between populations. The neighbor-joining tree based on genetic distance revealed that significant genealogical structure existed throughout the examined range of the Bombay duck. The results demonstrated that SRAP marker was an effective tool for the assessment of genetic diversity in the Bombay duck. The results could be used for further protection of the germplasm resource of the Bombay duck.

Assessment of the nutritive value of whole corn stover and its morphological fractions

This study investigated the chemical composition and ruminal degradability of corn stover in three maize-planting regions in Qiqihaer, Heilongjiang Province, China. The whole stover was separated into seven morphological fractions, i.e., leaf blade, leaf sheath, stem rind, stem pith, stem node, ear husk, and corn tassel. The assessment of nutritive value of corn stover and its fractions was performed based on laboratory assays of the morphological proportions, chemical composition, and in situ degradability of dry matter (DM), neutral detergent fiber (NDF), and acid detergent fiber (ADF). The chemical composition of corn stover was significantly different from plant top to bottom (p<0.05). Among the whole corn stover and seven morphological fractions, leaf blade had the highest crude protein (CP) content and the lowest NDF and ADF contents (p<0.05), whereas stem rind had the lowest CP content and the highest ADF and acid detergent lignin (ADL) contents (p<0.05). Ear husk had significantly higher NDF content and relatively lower ADL content than other corn stover fractions. Overall, the effective degradability of DM, NDF, and ADF in rumen was the highest in leaf blade and stem pith, followed by ear husk. The results indicate that leaf blade, ear husk, and stem pith potentially have higher nutritive values than the other fractions of corn stover. This study provides reference data for high-efficiency use of corn stover in feeding ruminants.

Expression of ERCC1 and BRCA1 predict the clinical outcome of non-small cell lung cancer in patients receiving platinum-based chemotherapy

We examined mRNA expression levels of ERCC1, BRCA1, RRM1, and human β-tubulin-III (TUBB3) in non-small-cell lung carcinoma (NSCLC) patients and investigated the association between expression of these genes and the clinical outcome of NSCLC treatment. A total of 366 patients who underwent surgery for NSCLC were included in this study. All patients received third-generation platinum-based chemotherapy as first-line treatment. The relative cDNA quantification for ERCC1, RRM1, BRCA1, and TUBB3 was determined using a fluorescence-based, real-time detection method. We found that low expression of ERCC1 and BRCA1 was associated with a good response to platinum-based chemotherapy, with an odds ratio [95% confidence interval (CI)] of 2.09 (1.33-3.27) and 2.92 (1.85-4.62), respectively. Multivariate Cox regression analysis indicated that patients with low expression of ERCC1 and BRCA1 attained a longer overall survival time than those with high expression, with a hazard ratio (95%CI) of 0.42 (0.23-0.77) and 0.39 (0.21-0.71), respectively. However, RMM1 and TUBB2 expressions were not correlated with clinical outcome of NSCLC. In conclusion, we found that low expression of ERCC1 and BRCA1 can be useful for selecting NSCLC patients who would benefit from chemotherapy and warrants further investigation in prospective studies.

Leaf functional trait variation associated with salt tolerance in perennial ryegrass

Salinity is one of major environmental stresses that dramatically threaten plant growth, and variations in genetic structure and functional traits have important effects on the salt tolerance of perennial ryegrass (Lolium perenne L.). The objectives of this study were to: (i) assess the inter-clonal variation of functional traits of accessions among geographic groups or between wild and commercial groups in response to salt stress; (ii) develop a mathematical model to effectively assess salt tolerance of perennial ryegrass accessions originating from different geographic populations; and (iii) determine the relation between spatial genetic structure and salt tolerance in perennial ryegrass. Wide variations were found among the accessions for seven functional traits. One regression model (F = 0.49 × F1 + 0.303 × F2 + 0.207 × F3) was established to ascertain salt tolerance of each accession. The highest variation of the traits and salt tolerance were obtained for accessions from the European group. Wild accessions exhibited more variation in functional traits and salt tolerance than commercial cultivars. Both molecular marker techniques and functional traits were used to conduct phylogenetic analysis, and the majority of accessions from the same or adjacent regions were clustered into the same group or subgroup. The perennial ryegrass accessions with similar salt tolerance had a close phylogenetic background. The patterns in functional trait variations associated with salt tolerance might allow acceleration of the process for improving salt stress resistance in perennial ryegrass.

Extracellular HSP70 peptide complexes alter expression of Glut1 and VEGF in HepG 2 cells via HIF-1α

AIM: To investigate the effect of extracellular heat shock protein 70 (HSP70)-peptide complexes (HSP70-PCs) on the expression of glucose transporter 1 (Glut1) and vascular endothelial growth factor (VEGF) in HepG2 cells and to explore the possible mechanisms involved.

METHODS: HepG2 cells were randomly divided into three groups: a control group, an extracellular HSP70 PC (final concentration, 2 μg/mL) group and an extracellular HSP70/HSP70-PCs + HIF-1α siRNA group. The expression of HIF-1α, Glut1 and VEGF was examined by real-time RT-PCR and Western blot.

RESULTS: Compared with the control group, the expression of HIF-1α, Glut1 and VEGF was significantly increased in the extracellular HSP70-PC group (all P < 0.05), suggesting that extracellular HSP70 PCs promote the expression of HIF-1α, Glut1 and VEGF in HepG2 cells. SiRNA-mediated blockage of HIF-1α significantly inhibited the up-regulation of Glut1 and VEGF expression in HepG2 cells (both P < 0.05).

CONCLUSION: Extracellular HSP70-PCs promote the expression of Glut1 and VEGF via HIF-1α in HepG 2 cells.

Mechanical and thermal properties of polypropylene (PP) composites filled with modified shell waste

Shell waste, with its high content of calcium carbonate (CaCO3) plus organic matrix, has a potential to be used as a bio-filler. In this work, shell waste was modified by furfural and then incorporated to reinforce polypropylene (PP). The shell waste and modified powder were characterized by means of X-ray diffraction (XRD), scanning electron microscopy equipped with an energy dispersive spectrometer (SEM-EDS), X-ray photoelectronic spectroscopy (XPS), and Fourier transformed infrared spectroscopy (FTIR). The mechanical and thermal properties of neat PP and PP composites were investigated as well. Thermal gravimetric (TG) analyses confirmed the reinforcing role of modified powder in PP composites. The mechanical properties studied showed that adding modified powder could significantly increase the impact strength, elongation at break point and flexural modulus of composites. The maximum incorporation content could reach 15 wt.% with a good balance between toughness and stiffness of PP composites. Differential scanning calorimetry (DSC) results showed that the modified powder could act as a nucleating agent and thus increase the crystallization temperature of PP. Polarized optical microscopy (POM) observation also indicated that the introduction of modified powder could promote the heterogeneous nucleation of PP matrix.

Characterization and molecular mapping of a dwarf mutant in wheat

A spontaneous dwarf mutant of wheat was found in an F5 generation line derived from a cross between Huamai No. 9 and Een No. 1 in 1998; it was named Huaai 01. We characterized the genetic pattern of Huaai 01 and mapped the gene controlling the dwarf trait. This dwarf mutant was found insensitive to exogenous gibberellic acid treatment, based on the length of the first leaf and the coleoptile at the seedling stage, suggesting that it plays a crucial role in the gibberellin response pathway. Genetic analysis revealed that a single gene that is partially recessive controls the dwarf phenotype in Huaai 01. We named the dwarfing gene Rht-B2. Simple sequence repeats (SSR) were examined as identifying markers linked to the Rht-B2 gene in an F2 population. We screened 904 pairs of primers and identified 5 SSR markers linked to the Rht-B2 gene. Two markers, barc1096 and xgwm495, were located on the flanking region of the Rht-B2 gene at genetic distances of 2.9 and 3.3 cM, respectively. Based on published SSR linkage data for wheat, the Rht-B2 gene was mapped to the long arm of chromosome 4B. This identification and characterization of the Rht-B2 dwarfing gene will facilitate its utilization in wheat breeding.

LPS regulates epithelial-mesenchymal transition in cholangiocarcinoma cell line ICBD via the p38/MAPK signaling pathway

AIM: To investigate the effect of LPS on epithelial-mesenchymal transition (EMT) of cholangiocarcinoma ICBD cells and to explore the possible mechanisms involved.

METHODS: ICBD cells were randomly divided into four groups: a control group, a LPS (final concentration, 10 μg/mL) group, a LPS + siRNA group, and a LPS + SB203580 group. The expression of epithelial cell surface marker E-Cadherin, stromal cell surface marker Vimentin, TLR4 and p38 was examined by real-time RT-PCR and Western blot.

RESULTS: LPS promoted the initiation of EMT of ICBD cells. The expression of TLR4 and p38 significantly increased in the process of EMT of ICBD cells. SiRNA-mediated blockage of TLR4 inhibited the occurrence of EMT and the up-regulation of p38 in ICBD cells. When p38 was blocked by SB-203580, the expression of TLR4 was still up-regulated, but EMT of ICBD cells did not occur compared to the control group.

CONCLUSION: LPS may activate TLR4 and promote EMT of cholangiocarcinoma cells via the p38/MAPK signaling pathway.

Influences of Sr dose on the crystal structure parameters and Sr distributions of Sr-incorporated hydroxyapatite

Stoichiometric strontium-incorporated hydroxyapatite (Sr-HA) with different Sr concentrations [Sr/(Sr+Ca)] were synthesized using a wet chemical approach and characterized by X-ray diffraction, Fourier-transformed infrared absorption, X-ray photoelectron spectroscopy, and Rietveld Structure Refinement. The crystal lattice parameter, Sr distribution, chemical state of Sr, and also the relationships between their variations and the Sr concentrations have been intensively studied. The results show that both the crystal lattice parameters and crystal plane space of Sr-HA remarkably increase with the Sr concentration increasing. Whether Sr preferably occupies the Ca(I) site or Ca(II) site after incorporated into apatite lattice depends on the Sr number incorporated into apatite. All the Sr ions completely occupy the Ca(II) sites when the Sr concentration is below 5%. With the exception of partial Sr ions occupying the Ca(II) sites, the other Sr ions start to occupy the Ca(I) sites when the Sr concentration doped in HA is beyond 10%. The ratio of Sr ions occupying the Ca(I) sites increases with the further raising Sr concentration up to 20%. The Sr ions inherit the chemical state and environment of the original Ca(I) or Ca(II) site after incorporated into apatite.

Using biochemical system to improve cinnabar dissolution

In order to evaluate the leaching of cinnabar, a chemobiological reactor system with Acidithiobacillus ferrooxidans for cinnabar dissolution was investigated. The results demonstrated cinnabar dissolution had relation to bioprocess of A. ferrooxidans and iron concentration tightly. The optimal dilution rate and iron concentration were 0.4/h and 2-3 g/L in chemobiological reactor. The process may be contributed to the indirect catalyzing of ferric iron generated with A. ferrooxidans and direct adherence oxidation function. This research shows the new microbiological technique may be a feasible and economical method in application.

Thymic stromal lymphopoietin: a promising therapeutic target for allergic diseases

Thymic stromal lymphopoietin (TSLP), an interleukin 7-like cytokine, can trigger dendritic cell (DC)-mediated T-helper type 2 (Th2) inflammatory responses. Recent evidence demonstrates that cytokines TSLP and OX40 (CD134)/OX40 ligand seem to be important players in the maintenance of Th2 memory pool in the pathogenesis of asthma. Accumulating data reveal that the pathogenic T cells involved in asthma are likely to be inflammatory Th2 cells. TSLP is involved in the development of asthma through crosstalk with nuclear factor NF-ĸB. Progression of skin fibrosis in atopic dermatitis occurs via TSLP/TSLP receptor. TSLP-mediated dermal inflammation aggravates experimental allergic asthma. Also, TSLP polymorphisms are associated with susceptibility to asthma, atopic dermatitis, and eczema herpeticum. These findings suggest a master switch of TSLP in the initiation of allergic and adaptive inflammation through innate pathways at the epithelial cell-DC interface. The TSLP pathway is therefore a promising target for immunotherapy of allergic diseases.

Development of microsatellite markers for the small yellow croaker Larimichthys polyactis (Sciaenidae) by cross-species amplification

The small yellow croaker (Larimichthys polyactis) is a highly valued fish for human consumption found in the Western Pacific that was considered endangered until recently because of overfishing. We selected microsatellite markers for this species from markers developed for Miichthys miiuy, also of the family Sciaenidae. Among 43 markers polymorphic for M. miiuy, 11 were found to be polymorphic for L. polyactis. Characterization of these 11 loci was made based on 30 L. polyactis individuals collected by trawling in the Zhoushan Fishing Ground, Zhejiang Province, China. Total genomic DNA was isolated from fin clips. The number of alleles per locus ranged from 4 to 10, with a mean of 5.82, while the effective number of alleles ranged from 1.64 to 10.00, with a mean of 3.22. Observed and expected heterozygosities ranged from 0.17 to 0.72 and from 0.39 to 0.81, respectively. Significant deviation from Hardy-Weinberg equilibrium was found at four loci, after applying Bonferroni's correction. There was no significant association between any of the pairs of microsatellite loci, hence allelic variation at these loci was considered independent. These 11 polymorphic microsatellite loci will be useful for genetic diversity analysis and molecular-assisted breeding for L. polyactis.

Genetic diversity of Setipinna taty (Engraulidae) populations from the China Sea based on mitochondrial DNA control region sequences

The genetic diversity of Setipinna taty, which is commercially fished in the China Sea, was studied based on mitochondrial DNA control region sequences. PCR was used to amplify the control region fragment in 100 individuals of S. taty collected from Weihai (WH), Yantai (YT), Zhoushan (ZS), Xiangshan (XS), and Ninghai (NH) in China. A control region fragment of 656 bp was successfully sequenced in these 100 individuals. The A+T content of this S. taty control region was 71.7%; 172 variable sites and 62 haplotypes were found. Nucleotide diversity in the WH, YT, ZS, XS, and NH groups was 0.0228, 0.0247, 0.0441, 0.0126, and 0.0238, respectively. The haplotype diversity was 0.984, 0.911, 0.989, 0.926, and 0.979, respectively. Analysis of molecular variance showed that 97.95% of genetic variation was within populations, and only 2.05% among populations. The neighbor-joining phylogenetic tree obtained based on genetic distance showed that no significant genealogical structure exists throughout this range of S. taty. These results indicate no apparent geographical differentiation in the comparison of Yellow Sea and East China Sea populations of S. taty. Within the control region, we identified an extended termination-associated sequence domain, a central conserved sequence block domain and a conserved sequence block domain; insertions of short tandem repeat sequence segments were found at the 5' end of the control region.

Advanced phosphorus removal for secondary effluent using a natural treatment system

Mechanisms for low concentrations phosphorus removal in secondary effluent were studied, and a process was developed using limestone filters (LF), submerged macrophyte oxidation ponds (SMOPs) and a subsurface vertical flow wetland (SVFW). Pilot scale experimental models were applied in series to investigate the advanced purification of total phosphorus (TP) in secondary effluent at the Chengjiang sewage treatment plant. With a total hydraulic residence time (HRT) of 82.52 h, the average effluent TP dropped to 0.17 mg L(-1), meeting the standard for Class III surface waters. The major functions of the LF were adsorption and forced precipitation, with a particulate phosphorus (PP) removal of 82.93% and a total dissolved phosphorus (TDP) removal of 41.07%. Oxygen-releasing submerged macrophytes in the SMOPs resulted in maximum dissolved oxygen (DO) and pH values of 11.55 mg L(-1) and 8.10, respectively. This regime provided suitable conditions for chemical precipitation of TDP, which was reduced by a further 39.29%. In the SVFW, TDP was further reduced, and the TP removal in the final effluent reached 85.08%.

A new inducible expression system in a transformed green alga, Chlorella vulgaris

Genetic transformation is useful for basic research and applied biotechnology. However, genetic transformation of microalgae is usually quite difficult due to the technical limitations of existing methods. We cloned the promoter and terminator of the nitrate reductase gene from the microalga Phaeodactylum tricornutum and used them for optimization of a transformation system of the microalga Chlorella vulgaris. This species has been used for food production and is a promising candidate as a bioreactor for large-scale production of value-added proteins. A construct was made containing the CAT (chloramphenicol acetyltransferase) reporter gene driven by the nitrate reductase promoter. This construct was transferred into the C. vulgaris genome by electroporation. Expression of CAT in transgenic Chlorella conferred resistance to the antibiotic chloramphenicol and enabled growth in selective media. Overall efficiency for the transformation was estimated to be approximately 0.03%, which is relatively high compared with other available Chlorella transformation systems. Expression of CAT was induced in the presence of nitrate and inhibited in the presence of ammonium as a sole nitrogen source. This study presented an inducible recombinant gene expression system, also providing more gene regulation elements with potential for biotechnological applications.