Use of the STR loci D18S53, D18S59, and D18S488 in the diagnosis of Edwards’ syndrome

The aim of this study was to investigate the feasibility of using short tandem repeats (STRs) to diagnose Edwards’ syndrome (ES). Quantitative fluorescence polymerase chain reaction (QF-PCR) was performed to amplify STR loci on chromosome 18, specifically D18S53, D18S59, and D18S488. The amplified products were subjected to a fluorescence signal analysis and their application to ES diagnosis was examined. Among the 807 cases that showed normal results in the karyotype analysis, 793 showed one or two fluorescence bands with a fluorescence intensity ratio of 1:1, and 14 cases showed 3 bands, which were false-positive results. ES was diagnosed in 9 samples. The sensitivities of D18S53, D18S59, and D18S488 for the diagnosis of ES were 77.78, 44.44, and 55.56 % and the specificities were 96.16, 96.03, and 96.28 %, respectively. The combined sensitivity of the three loci for diagnosing DS was 100 % (9/9), with a specificity of 98.27 % (793/807). QF-PCR amplification of STR loci had high sensitivity, strong specificity, and was simple and rapid. Thus, it might have wide clinical applications, and could be an ideal tool for large-scale genetic and prenatal diagnosis of ES.     

Structure and Function of Hainantoxin-III,a Selective Antagonist of Neuronal Tetrodotoxin-sensitive Voltage-gated Sodium Channels Isolated from the Chinese Bird Spider Ornithoctonus hainana

In the present study, we investigated the structure and function of hainantoxin-III (HNTX-III), a 33-residue polypeptide from the venom of the spider Ornithoctonus hainana. It is a selective antagonist of neuronal tetrodotoxin-sensitive voltage-gated sodium channels. HNTX-III suppressed Nav1.7 current amplitude without significantly altering the activation, inactivation, and repriming kinetics. Short extreme depolarizations partially activated the toxin-bound channel, indicating voltage-dependent inhibition of HNTX-III. HNTX-III increased the deactivation of the Nav1.7 current after extreme depolarizations. The HNTX-III·Nav1.7 complex was gradually dissociated upon prolonged strong depolarizations in a voltage-dependent manner, and the unbound toxin rebound to Nav1.7 after a long repolarization. Moreover, analysis of chimeric channels showed that the DIIS3-S4 linker was critical for HNTX-III binding to Nav1.7. These data are consistent with HNTX-III interacting with Nav1.7 site 4 and trapping the domain II voltage sensor in the closed state. The solution structure of HNTX-III was determined by two-dimensional NMR and shown to possess an inhibitor cystine knot motif. Structural analysis indicated that certain basic, hydrophobic, and aromatic residues mainly localized in the C terminus may constitute an amphiphilic surface potentially involved in HNTX-III binding to Nav1.7. Taken together, our results show that HNTX-III is distinct from β-scorpion toxins and other β-spider toxins in its mechanism of action and binding specificity and affinity. The present findings contribute to our understanding of the mechanism of toxin-sodium channel interaction and provide a useful tool for the investigation of the structure and function of sodium channel isoforms and for the development of analgesics.     

Effect of wood hardness and secondary compounds on feeding preference of Odontotermes formosanus (Isoptera: Termitidae)

Odontotermes formosanus (Shiraki) (Isoptera: Termitidae) is one of the most destructive plant pests in China, which control relies mainly on baits strategies. Baits made from the wood of eight different tree species were used to study the feeding preference of this termite, and conversely wood protection strategies of the tree species. Three bait types were used to identify wood protection strategies: solid wood (physical and chemical protection), crude flour (chemical protection) made from ground wood, and extracted flour (no protection) made by extracting crude flour with ethanol and toluene. Feeding preference was influenced by wood species and bait type. For solid wood, Magnolia denudata Desr (75%) and Elaeocarpus glabripetalus Merr (41%) were most preferred; for crude flour, E. glabripetalus (97%) and Quercus variabilis Blume (92%) were most preferred; and for extracted flour, there were no significant differences between wood species, demonstrating the influence of chemical defense. The greatest contrast between bait types was for Platanus orientalis L, the least preferred as solid wood and crude flour, suggesting that chemical defense compounds are particularly important in this species. Solid wood consumption was inversely correlated with wood density. Extracted flour consumption was positively correlated with glucose concentration. There was no direct effect of holocellulose and other components tested. O. formosanus preferred to fed on soft wood with low chemical protection (M. denudata); conversely trees protected their wood either physically [e.g., E. glabripetalus, Q. variabilis, Cinnamomum camphora (L.) Presl, and Ligustrum lucidum Aiton] or chemically (Populus bonati Levl) or a combination of both strategies (Liquidamba formosana Hance and P. orientalis).     

Mutagenesis of GmFT2a and GmFT5a mediated by CRISPR/Cas9 contributes for expanding the regional adaptability of soybean

Flowering time is a key agronomic trait that directly influences the successful adaptation of soybean (Glycine max) to diverse latitudes and farming systems. GmFT2a and GmFT5a have been extensively identified as flowering activators and integrators in soybean. Here, we identified two quantitative trait loci (QTLs) regions harbouring GmFT2a and GmFT5a, respectively, associated with different genetic effects on flowering under different photoperiods. We analysed the flowering time of transgenic plants overexpressing GmFT2a or GmFT5a, ft2a mutants, ft5a mutants and ft2aft5a double mutants under long‐day (LD) and short‐day (SD) conditions. We confirmed that GmFT2a and GmFT5a are not redundant, they collectively regulate flowering time, and the effect of GmFT2a is more prominent than that of GmFT5a under SD conditions whereas GmFT5a has more significant effects than GmFT2a under LD conditions. GmFT5a, not GmFT2a, was essential for soybean to adapt to high latitude regions. The ft2aft5a double mutants showed late flowering by about 31.3 days under SD conditions and produced significantly increased numbers of pods and seeds per plant compared to the wild type. We speculate that these mutants may have enormous yield potential for the tropics. In addition, we examined the sequences of these two loci in 202 soybean accessions and investigated the flowering phenotypes, geographical distributions and maturity groups within major haplotypes. These results will contribute to soybean breeding and regional adaptability.     

Increased Expression of Lin28B Associates with Poor Prognosis in Patients with Oral Squamous Cell Carcinoma

Recent studies showed that incomplete cell reprogramming can transform cells into tumour-like cells. Lin28A is associated with fibroblast and sarcoma cell reprogramming, whereas its homologue Lin28B is associated with hematopoietic cell reprogramming. This study aimed to investigate the expression and prognostic difference between Lin28A and Lin28B in oral squamous cell carcinoma (OSCC). Expression level was assessed by immunohistochemistry and staining location was confirmed by immunofluorescence. Prognostic values were analysed and compared by the Kaplan–Meier analysis and uni and multivariate Cox regression models. Besides, in vitro cell assays and in vivo nude mice xenograft were used to demonstrate the influence of increased Lin28B expression in OSCC. Lin28A and Lin28B expression increased in OSCC, and co-expression of Lin28A and Lin28B showed no significant association with patient prognosis. Kaplan–Meier analysis showed that patients with high Lin28B but not Lin28A expression had lower overall survival (OS) rates than those with low Lin28B expression. Further Univariate analysis showed that patients with increased Lin28B expression had shorter disease-free survival (DFS) and shorter OS, while multivariate analysis showed Lin28B overexpression with TNM stage predicted poor prognosis in patients with OSCC. Besides, stable expressing Lin28B in oral cancer cells promoted cell migration, invasion, colony formation, in vivo proliferation and increased the expression of cancer suppressor miRNA let-7 targeted genes IL-6, HMGA2, the EMT markers Snail and Twist, the angiogenesis inducer VEGF, and the apoptosis inhibitor Survivin. These combined results indicate that Lin28B is a novel marker for predicting prognosis in patients with OSCC and may be a therapeutic target.     

Genetic background and environmental conditions drive metabolic variation in wild type and transgenic soybean (Glycine max) seeds

The metabolic profiles and composition of storage reserves of agricultural crop seeds are strongly regulated by heritable and environmental factors. Yet, very little is known about the genetic and environmental determinants of adaptive metabolic variation amongst wild type as well as transgenic seed populations derived from the same genetic background, grown under natural field conditions. The goal of the current study was to investigate the effects of natural environmental conditions on wild type and transgenic soybean seeds expressing a feedback‐insensitive form of cystathionine γ‐synthase, a methionine main regulatory enzyme. The seeds were grown in four geographically distinct habitats in China and then assayed for primary metabolic profiles using gas chromatography mass spectrometry, morphological traits and storage reserve accumulation. The analyses revealed changes in the levels of primary metabolites which evidently exhibited high correlation to methionine regardless of changes in environmental conditions. The environment, however, constituted a major determinant of metabolic profiles amongst seeds, as much more metabolites were observed to be affected by this variable, particularly along the north‐to‐south latitudinal gradient. The observations suggest that metabolic variation amongst seeds grown under natural field conditions depends upon the complex relationships existing amongst their genetic background and the environmental conditions characterizing their cultivation areas.     

CRISPR/Cas9-Mediated Genome Editing in Soybean Hairy Roots

As a new technology for gene editing, the CRISPR (clustered regularly interspaced short palindromic repeat)/Cas (CRISPR-associated) system has been rapidly and widely used for genome engineering in various organisms. In the present study, we successfully applied type II CRISPR/Cas9 system to generate and estimate genome editing in the desired target genes in soybean (Glycine max (L.) Merrill.). The single-guide RNA (sgRNA) and Cas9 cassettes were assembled on one vector to improve transformation efficiency, and we designed a sgRNA that targeted a transgene (bar) and six sgRNAs that targeted different sites of two endogenous soybean genes (GmFEI2 and GmSHR). The targeted DNA mutations were detected in soybean hairy roots. The results demonstrated that this customized CRISPR/Cas9 system shared the same efficiency for both endogenous and exogenous genes in soybean hairy roots. We also performed experiments to detect the potential of CRISPR/Cas9 system to simultaneously edit two endogenous soybean genes using only one customized sgRNA. Overall, generating and detecting the CRISPR/Cas9-mediated genome modifications in target genes of soybean hairy roots could rapidly assess the efficiency of each target loci. The target sites with higher efficiencies can be used for regular soybean transformation. Furthermore, this method provides a powerful tool for root-specific functional genomics studies in soybean.     

贡嘎蝠蛾卵的扫描电镜和生物学观察

贡嘎蝠蛾卵呈椭圆形,在扫描电镜下卵壳表面分为一般卵壳区和受精孔区：一般卵壳区密布颗粒状突起;受精孔区位于卵端部,呈不规则梨形垫状,精孔开口于突起内侧凹陷上部。贡嘎蝠蛾在6月下旬—7月产卵,散产。在平均温度8－10℃、相对湿度80％－90％,卵的发育历期为50天左右,孵化率75％以上。卵常遭受霉菌和寄生蜂天敌危害。     

药用红花综合农艺数学模型的研究

根据系统理论的思想和方法,采用控制论的“黑箱”原理,运用二次正交回归旋转组合设计,进行田间试验,以整体功能最佳为目标,建立药用红花的综合农艺措施数学模型,通过分析、模拟、优化并结合最优净产值农艺措施组合,筛选出高产优质高效综合农艺措施．根据系统理论的思想和方法,采用控制论的“黑箱”原理,运用二次正交回归旋转组合设计,进行田间试验,以整体功能最佳为目标,建立药用红花的综合农艺措施数学模型Ya在本试验中各项农艺措施对产量的影响大小为：氮肥＞播期、磷肥＞密度＞钾肥．播期与N,P,K之间存在互作效应,氮肥、磷肥和钾肥之间也有互作效应．通过对上述模型进行分析、模拟、优化并结合最优净产值农艺措施组合,筛选出高产优质高效综合农艺措施为：播期30／10—2／11,密度12500—13100株／亩,亩施肥量N：5.7—6.5Kg.P_2O_5：8.0—9.0Kg,K_2O5.0—6.1Kg．实施该优化组合方案,药用红花干花产量在18Kg／亩以上,净产值为340元／亩以上．在推广中,应根据各地的气候、土壤、肥料来源等具体条件,作适当调整,不断修正、反馈信息,使之不断完善,以达到整体最优的目标,充分发挥其增产潜力．