Microsatellite DNA markers for analysis of population structure in the sea urchin Centrostephanus rodgersii

We describe the development of 13 variable microsatellites developed to investigate population structure and dispersal in the sea urchin Centrostephanus rodgersii. This species is the dominant grazing herbivore in southeast Australian coastal waters and has the ability to modify benthic community structure. The microsatellites we identified showed a range of allele numbers (4–21) and expected heterozygosity (0.32–0.91) in two sampled populations. Contrary to previous findings in free‐spawning marine invertebrates, genotype proportions in neither population deviated significantly from Hardy–Weinberg expectations.     

Characterization of polymorphic tetranucleotide microsatellite loci from the Siberian weasel (Mustela sibirica)

Nine tetrarepeat microsatellite loci for Siberian weasel (Mustela sibirica) were characterized. By using 35 individuals of unknown relationship collected from Taiwan, we evaluated the polymorphism of these loci. The number of alleles for each locus ranged from five to 12 (mean = 8.78 alleles) and the observed heterozygosity from 0.429 to 0.962 (mean = 0.688) and all loci conformed to Hardy–Weinberg expectation.     

Altered motor activity, exploration and anxiety in heterozygous neuregulin 1 mutant mice: implications for understanding schizophrenia

Human genetic studies have shown that neuregulin 1 (NRG1) is a potential susceptibility gene for schizophrenia. Nrg1 influences various neurodevelopmental processes, which are potentially related to schizophrenia. The neurodevelopmental theory of schizophrenia suggests that interactions between genetic and environmental factors are responsible for biochemical alterations leading to schizophrenia. To investigate these interactions and to match experimental design with the pathophysiology of schizophrenia, we applied a comprehensive behavioural phenotyping strategy for motor activity, exploration and anxiety in a heterozygous Nrg1 transmembrane domain mutant mouse model (Nrg1 HET) using different housing conditions and age groups. We observed a locomotion- and exploration-related hyperactive phenotype in Nrg1 HETs. Increased age had a locomotion- and exploration-inhibiting effect, which was significantly attenuated in mutant mice. Environmental enrichment (EE) had a stimulating influence on locomotion and exploration. The impact of EE was more pronounced in Nrg1 hypomorphs. Our study also showed a moderate task-specific anxiolytic-like phenotype for Nrg1 HETs, which was influenced by external factors. The behavioural phenotype detected in heterozygous Nrg1 mutant mice is not specific to schizophrenia per se, but the increased sensitivity of mutant mice to exogenous factors is consistent with the pathophysiology of schizophrenia and the neurodevelopmental theory. Our findings reinforce the importance of carefully controlling experimental designs for external factors and of comprehensive, integrative phenotyping strategies. Thus, Nrg1 HETs may, in combination with other genetic and drug models, help to clarify pathophysiological mechanisms behind schizophrenia.     

Peptide probes containing a non-hydrolyzable phosphotyrosine-mimetic residue for enrichment of protein tyrosine phosphatases

We developed peptide probes containing a non-hydrolyzable phosphotyrosine mimetic, 4-[difluoro(phosphono)methyl]-L-phenylalanine (F₂Pmp) for the enrichment of protein tyrosine phosphatases (PTPs). We found that different F₂Pmp probes can enrich different PTPs, depending on the probe sequence. Furthermore, proteins containing a Src homology 2 (SH2) domain were enriched together. Importantly, probes containing phosphotyrosine instead of F₂Pmp failed to enrich PTPs due to dephosphorylation during the pulldown step. This enrichment approach using peptides containing F₂Pmp could be a generic tool for tyrosine phosphatome analysis without the use of antibodies.     

Virtual screening of active compounds from Artemisia argyi and potential targets against gastric ulcer based on Network pharmacology

Artemisia argyi (AA) is one of the renowned herbs in China often used in the treatment of gastric ulcer (GU). Aiming to predict the active compounds and systematically investigate the mechanisms of Artemisia argyi for GU treatment, the approach of network pharmacology, molecular docking, gene ontology (GO) analysis, and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis were adopted, respectively, in present study. A total of 13 predicted targets of the 103 compounds in Artemisia argyi were obtained. Sorted by pathogenic mechanisms of targets and structure types of compounds, it was revealed that flavonoids and sesquiterpenes had better performance than monoterpenes. The network analysis showed that Phospholipase a2 (PA21B), Sulfotransferase family cytosolic 2b member 1 (ST2B1), Nitric-oxide synthase, endothelial (NOS3), Gastrin (GAST), neutrophil collagenase (MMP-8), Leukotriene A-4 hydrolase (LKHA4), Urease maturation factor HypB (HYPB), and Periplasmic serine endoprotease DegP (HtrA) were the key targets with intensely interaction. The functional enrichment analysis indicated that AA probably produced the gastric mucosa protection effects by synergistically regulating many biological pathways, such as NF-κB signaling pathway, HIF-1 signaling pathway, TNF signaling pathway, VEGF signaling pathway, and Toll-like receptor signaling pathway, etc. In addition, C73 and C15 might be promising leading compounds with good molecular docking score. As a consequence, this study holistically illuminates the active constituents and mechanisms based on data analysis, which contributes to searching for leading compounds and the development of new drugs for gastric ulcer.     

食物中多不饱和脂肪酸在家蝇幼虫体内的富集与代谢及对其生长的影响

【目的】阐明家蝇 Musca domestica 幼虫对食物中各种多不饱和脂肪酸的富集能力以及代谢转化情况,并探究各种多不饱和脂肪酸对家蝇幼虫生长的影响。【方法】在基础饲料中添加不同浓度(3%, 6%和12%)的多不饱和脂肪酸(亚油酸、α-亚麻酸、花生四烯酸和二十二碳六烯酸)饲养经过脱脂传代培养的家蝇幼虫;提取家蝇幼虫的总脂肪酸,利用气相色谱仪进行检测和分析;测定统计幼虫体重,以分析多不饱和脂肪酸对家蝇幼虫生长的影响。【结果】亚油酸、α-亚麻酸和花生四烯酸在家蝇幼虫体内均能被富集,且它们的富集程度随着食物中多不饱和脂肪酸的添加浓度的升高而增加,其中亚油酸、α-亚麻酸和花生四烯酸在幼虫体内富集的最高含量(占体内总脂肪酸的比例)分别为21.93%, 16.13%和9.68%,而二十二碳六烯酸不能在家蝇幼虫体内富集,提示家蝇幼虫食物中添加的各种多不饱和脂肪酸经过代谢后并没有在其体内产生新的脂肪酸,而食物中添加的二十二碳六烯酸在家蝇幼虫体内被分解代谢后消除。饲喂α-亚麻酸及花生四烯酸后家蝇幼虫体重增长较为明显,其中6%α-亚麻酸添加组的幼虫体重显著高于对照组(取食脱脂饲料)和3%和12%α-亚麻酸添加组,3%和6%花生四烯酸添加组的幼虫体重显著高于对照组和12%花生四烯酸添加组。【结论】家蝇幼虫体内能够从食物中富集部分多不饱和脂肪酸,多不饱和脂肪酸碳链越长其富集程度越低直至不能富集,富集的多不饱和脂肪酸对家蝇幼虫生长有不同程度的影响。     

Development of α4 integrin DNA aptamer as a potential therapeutic tool for multiple sclerosis

One of the most important molecules for multiple sclerosis pathogenesis is α4 integrin, which is responsible for autoreactive leukocytes migration into the brain. The monoclonal antibody, natalizumab, was introduced to market for blocking the extravasation of autoreactive leukocytes via inhibition of α4 integrin. However, the disadvantages of antibodies provided a suitable background for other agents to be replaced with antibodies. Considering the profound advantages of aptamers over antibodies, aptamer isolation against α4 integrin was intended in the current study. The α4 integrin-specific aptamers were selected using cell-systematic evolution of ligands by exponential enrichment (SELEX) method with human embryonic kidney (HEK)-293T overexpressing α4 integrin and HEK-293T as target and control cells, respectively. Evaluation of selected aptamer was performed through flow cytometric analysis. The selected clones were then sequenced and analyzed for any possible secondary structure and affinity. The results of this study led to isolation of 13 different single-stranded DNA clones in 11 rounds of selection which were categorized to three clusters based on common structural motifs and the equilibrium dissociation constant (K _d) of the most stable structure was calculated. The evaluation of SELEX progress showed growth in aptamer affinity with increasing of the number of cycles. Taken together, the findings of this study demonstrated the isolation of α4-specific single-stranded DNA aptamers with suitable affinity for ligand, which can further be replaced with natalizumab.     

An analytical enrichment-based review of structural genetic studies on keratoconus

Keratoconus is a progressive bilateral corneal protrusion that leads to irregular astigmatism and impairment of vision. Keratoconus is an etiologically heterogeneous corneal dystrophy and both environmental and genetic factors play a role in its etiopathogenesis. In this analytical review, we have studied all the genes that are structurally associated with keratoconus and have tried to explain the function of each gene and its association with other eye disorders in a concise way. In addition, using gene set enrichment analysis, it was attempted to find the most important impaired metabolic pathways in keratoconus. Several genetic studies have been carried out on keratoconus and several genes have been identified as risk factors involved in the etiology of the disease. In the current study, 16 studies, including nine association studies, five genome-wide association studies, one linkage study, and one meta-analysis, were reviewed and based on the 19 genes found, enrichment was performed and the most important metabolic pathways involved in the disease were identified. The enrichment results indicated that the two pathways, interleukin 1 processing and assembly of collagen fibrils, are significantly associated with the disease. Obviously, the results of this study, in addition to providing information about the genes involved in the disease, can provide an integrated insight into the gene-based etiology of keratoconus and therapeutic opportunities thereof.