Estimating the inbreeding level and genetic relatedness in an isolated population of critically endangered Sichuan taimen (Hucho Bleekeri) using genome‐wide SNP markers

Sichuan taimen (Hucho bleekeri) is critically endangered fish listed in The Red List of Threatened Species compiled by the International Union for Conservation of Nature (IUCN). Specific locus amplified fragment sequencing (SLAF‐seq)‐based genotyping was performed for Sichuan taimen with 43 yearling individuals from three locations in Taibai River (a tributary of Yangtze River) that has been sequestered from its access to the ocean for more than 30 years since late 1980s. Applying the inbreeding level and genetic relatedness estimation using 15,396 genome‐wide SNP markers, we found that the inbreeding level of this whole isolated population was at a low level (2.6 × 10^?3 ± 0.079), and the means of coancestry coefficients within and between the three sampling locations were all very low (close to 0), too. Genomic differentiation was negatively correlated with the geographical distances between the sampling locations (p < .001), and the 43 individuals could be considered as genetically independent two groups. The low levels of genomic inbreeding and relatedness indicated a relatively large number of sexually mature individuals were involved in reproduction in Taibai River. This study suggested a genomic‐relatedness‐guided breeding and conservation strategy for wild fish species without pedigree information records.     

ARL4C might serve as a prognostic factor and a novel therapeutic target for gastric cancer: bioinformatics analyses and biological experiments

The ADP-ribosylation factor-like proteins (ARLs) have been proved to regulate the malignant phenotypes of several cancers. However, the exact role of ARLs in gastric cancer (GC) remains elusive. In this study, we systematically investigate the expression status, interactive relations, potential pathways, genetic variations and clinical values of ARLs in GC. We find that ARLs are significantly dysregulated in GC and involved in various cancer-related pathways. Subsequently, machine learning models identify ARL4C as one of the two most significant clinical indicators among ARLs for GC. Furthermore, ARL4C silencing remarkably inhibits the growth and metastasis of GC cells both in vitro and in vivo. Moreover, enrichment analysis indicates that ARL4C is highly correlated with TGF-β1 signalling. Correspondingly, TGF-β1 treatment dramatically increases ARL4C expression and ARL4C knockdown inhibits the phosphorylation level of Smads, downstream factors of TGF-β1. Meanwhile, the coexpression of ARL4C and TGF-β1 worsens the prognosis of GC patients. Our work comprehensively demonstrates the crucial role of ARLs in the carcinogenesis of GC and the specific mechanisms underlying the GC-promoting effects of TGF-β1. More importantly, we uncover the great promise of ARL4C-targeted therapy in improving the efficacy of TGF-β1 inhibitors for GC patients.     

适当浓度的过氧化氢诱导人支气管上皮细胞发生钙振荡

包括过氧化氢（Hzoz）在内的活性氧通过引起细胞内钙的变化而造成细胞损伤。然而,不同浓度的H202可以导致细胞内不同的钙变化,并激活不同的信号通路。细胞内钙振荡是其中的一种钙信号变化形式,钙振荡可以调控转录因子NF—KB的活性。该研究探讨可以诱导支气管上皮细胞内钙振苏发生的H2o2浓度。体外培养人支气管上皮细胞,采取钙离子荧光探针Fura_2标记细胞。并使用离子成像系统,观测不同浓度的H：0：（0～1000μmol／L）作用下细胞内钙浓度的变化。结果发现,低于50μmol／L的H202仅仅引起“钙火花”;50～500μmol／L的H202导致细胞内钙振荡的发生;而1000μmol／L的H202引起细胞内持续的高钙;同时也证实150μmol／L的H202诱发明显的钙振荡,而钙振荡随后引起了NF—KB活性的升高。该研究提示,适当浓度的H：0：可以诱发支气管上皮细胞内钙振荡的发生,推测可能是活性氧导致慢性气道炎症损伤的一个机制。     

Genome-Wide Analyses of Radioresistance-Associated miRNA Expression Profile in Nasopharyngeal Carcinoma Using Next Generation Deep Sequencing

Background

Rapidly growing evidence suggests that microRNAs (miRNAs) are involved in a wide range of cancer malignant behaviours including radioresistance. Therefore, the present study was designed to investigate miRNA expression patterns associated with radioresistance in NPC.

Methods

The differential expression profiles of miRNAs and mRNAs associated with NPC radioresistance were constructed. The predicted target mRNAs of miRNAs and their enriched signaling pathways were analyzed via biological informatical algorithms. Finally, partial miRNAs and pathways-correlated target mRNAs were validated in two NPC radioreisitant cell models.

Results

50 known and 9 novel miRNAs with significant difference were identified, and their target mRNAs were narrowed down to 53 nasopharyngeal-/NPC-specific mRNAs. Subsequent KEGG analyses demonstrated that the 53 mRNAs were enriched in 37 signaling pathways. Further qRT-PCR assays confirmed 3 down-regulated miRNAs (miR-324-3p, miR-93-3p and miR-4501), 3 up-regulated miRNAs (miR-371a-5p, miR-34c-5p and miR-1323) and 2 novel miRNAs. Additionally, corresponding alterations of pathways-correlated target mRNAs were observed including 5 up-regulated mRNAs (ICAM1, WNT2B, MYC, HLA-F and TGF-β1) and 3 down-regulated mRNAs (CDH1, PTENP1 and HSP90AA1).

Conclusions

Our study provides an overview of miRNA expression profile and the interactions between miRNA and their target mRNAs, which will deepen our understanding of the important roles of miRNAs in NPC radioresistance.     

A link between maze learning and hippocampal expression of neuroleukin and its receptor gp78

Neuroleukin (NLK) is a multifunctional protein involved in neuronal growth and survival, cell motility and differentiation, and glucose metabolism. We report herein that hippocampal expression of NLK and its receptor gp78 is associated with maze learning in rats. First, mRNA levels of NLK and gp78 were significantly increased in hippocampi of male Fischer-344 rats following training in the Stone T-maze and the Morris water maze. Second, a parallel increase was found in hippocampal NLK and gp78 proteins after maze learning. Third, NLK and gp78 mRNA and protein expression in hippocampus was reduced in a group of aged rats that showed more errors during the acquisition of the Stone maze task as compared with young rats. Finally, application of recombinant NLK to hippocampal neurons significantly enhanced glutamate-induced ion currents, functional molecular changes that have been correlated with learning in vivo. Taken together, our results identify a novel association of hippocampal expression of NLK and its receptor gp78 with rat maze learning. Interaction of NLK with gp78 and subsequent signaling may strengthen synaptic mechanisms underlying learning and memory formation.     

Molecular cloning and characterization of a mannose-binding lectin gene from Crinum asiaticum

Full-length cDNA of a mannose-binding lectin or agglutinin gene was cloned from a traditional Chinese medicinal herb Crinum asiaticum var. sinicum through RACE-PCR cloning. The full-length cDNA of C. asiaticum agglutinin (caa) was 820 bp and contained a 528 bp open reading frame encoding a lectin precursor (preproprotein) of 175 amino acid residues with a 22 aa signal peptide. The coding region of the caa gene was high in G/C content. The first 20 bp of the 5' UTR had a dC content of 50%, which was a typical feature of the leader sequence. By cutting away the signal peptide, the CAA proprotein was 15.79 kDa with a pl of 9.27 and contained 3 mannose-binding sites (QDNY). Random coil and extended strand constituted interlaced domination of the main part of the secondary structure. B-lectin conserved domain existed within N24 to G130. Predicted three-dimensional structure of CAA proprotein was very similar to that of GNA (Galanthus nivalis agglutinin). It is significant that besides certain homologies to known monocot mannose-binding lectins from Amaryllidaceae, Orchidaceae, Alliaceae and Liliaceae, caa also showed high similarity to gastrodianin type antifungal proteins. No intron was detected within the region of genomic sequence corresponding to the caa full-length cDNA. Southern blot analysis indicated that the caa gene belonged to a low-copy gene family. Northern blot analysis demonstrated that caa mRNA was constitutively expressed in all the tested tissue types including the root, bulb, leaf, rachise, flower and fruit tissues.     

Immobilization of <Emphasis Type="Italic">Escherichia coli</Emphasis> cells with <Emphasis Type="Italic">cis</Emphasis>-epoxysuccinate hydrolase activity for <Emphasis Type="SmallCaps">d</Emphasis>(−)-tartaric acid production

Immobilization of cis-epoxysuccinate hydrolase-containing E. coli for d(−)-tartaric acid production was screened by various methods. The highest recovery of activity was obtained by entrapment in κ-carrageenan gel. 23.6 g biomass/l and 43.4 g κ-carrageenan/l were the best immobilization conditions optimized by response surface methodology with 83% yield (114 U/g). Cell autolysis was observed after immobilization. Immobilized cells showed high pH (5–10) stability, thermal (up to 65°C) stability, conversion rate (>99.5%), enantioselectivity (ee > 99.6%), and were less affected by metal ions and surfactants compared with free cells. Conversion rate for immobilized cells preserved 93% after 10 repeated batches (5% for free cells).     

Enantioselective Degradation of Chiral Insecticide Dinotefuran in Greenhouse Cucumber and Soil

The enantioselective degradation behavior of the chiral insecticide dinotefuran in cucumber and soil was investigated under greenhouse conditions based on the method established with a normal‐phase high‐performance chromatography (HPLC) on a ChromegaChiral CCA column (250 × 4.6 mm, 5 µm, ES Industries). The linearity range, matrix effect, precision, and accuracy of the method were evaluated and the method was then successfully applied for the enantioselective analysis of dinotefuran in cucumber and soil. Significant enantioselectivity of degradation was observed in soil according to the results. The (+)‐dinotefuran was more persistent in soil with half‐life of 21.7 d, which is much longer than that of (–)‐dinotefuran (16.5 d). In cucumber, the (–)‐dinotefuran also tended to be preferentially degraded both in foliar and douche treatment. However, the statistical analysis indicated the enantioselectivity of degradation in cucumber was not significant. The research provides the first report concerning the enantioselective degradation of dinotefuran enantiomers and the results can be used for understanding the insect‐controlling effect and food safety evaluation. Chirality 27:137–141, 2015. © 2014 Wiley Periodicals, Inc.