Hydrophylita (Lutzimicron) emporos Shih & Polaszek (Hymenoptera: Trichogrammatidae) from Taiwan,Parasitising Eggs,and Phoretic on Adults,of the Damselfly Psolodesmus mandarinus mandarinus (Zygoptera: Calopterygidae)

Hydrophylita emporos n. sp. reared from eggs of Psolodesmus mandarinus mandarinus McLachlan (Zygoptera: Calopterygidae) in Taiwan is described. This is the first species of Hydrophylita to be described from the Old World, and the first record of phoresy in the genus. Adult females were observed aggregating at the base of the female damselfly’s abdomen. When the damselfly begins ovipositing, females move to the tip of the abdomen, enter the water and quickly locate eggs for parasitising. The article contains links to video footage of this process.     

Activin A affects feeding by promoting the inner diameter and muscle development of the pharynx and oesophagus in zebrafish (Danio rerio) larvae

Activin A belongs to the superfamily of transforming growth factor-β and plays an important role in hormone regulation and tissue development. However, few research studies have been conducted on the effect of activin A on feeding organs in fish. In this study, the zebrafish (Danio rerio) larvae were treated with 1 ng ml^–1 activin A for 8 days continuously. The haematoxylin and eosin (H&E) staining section results revealed that the transverse inner diameter of the pharynx and oesophagus significantly increased on the third and eighth days after treatment compared with the control group (P < 0.05). On the eighth day, the cross-sectional area of the pharyngeal muscle increased by 8638 μm² compared to the control group (P < 0.05). The RNA in situ hybridization results also showed that the expression of skeletal muscle-specific genes (myog and myod) was significantly increased in pharyngeal muscle on the eighth day. Furthermore, the qRT-PCR results showed the expression of gh gene was significantly increased on the eighth day (P < 0.05). At the same time, more larvae in activin A group were able to feed larger brine shrimp (Artemia) than in the control group on the eighth day. In conclusion, activin A could affect feeding by promoting the inner diameter and muscle development of the pharynx and oesophagus in zebrafish larvae. This study is the first to report that the development of the pharynx and oesophagus can directly affect food intake in fish larvae, which provides a theoretical basis for the study of food intake of fish at an early stage.     

Exploring ligand dissociation pathways from aminopeptidase N using random acceleration molecular dynamics simulation

Aminopeptidase N (APN) is a zinc-dependent ectopeptidase involved in cell proliferation, secretion, invasion, and angiogenesis, and is widely recognized as an important cancer target. However, the mechanisms whereby ligands leave the active site of APN remain unknown. Investigating ligand dissociation processes is quite difficult, both in classical simulation methods and in experimental approaches. In this study, random acceleration molecular dynamics (RAMD) simulation was used to investigate the potential dissociation pathways of ligand from APN. The results revealed three pathways (channels A, B and C) for ligand release. Channel A, which matches the hypothetical channel region, was the most preferred region for bestatin to dissociate from the enzyme, and is probably the major channel for the inner bound ligand. In addition, two alternative channels (channels B and C) were shown to be possible pathways for ligand egression. Meanwhile, we identified key residues controlling the dynamic features of APN channels. Identification of the dissociation routes will provide further mechanistic insights into APN, which will benefit the development of more promising APN inhibitors.

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Graphical Abstract The release pathways of bestatin inside active site of aminopeptidase N were simulated using RAMD simulation

     

Association of single nucleotide polymorphism rs2065955 of the filaggrin gene with susceptibility to Epstein-Barr virus-associated gastric carcinoma and EBV-negative gastric carcinoma

The relationship between the Filaggrin gene(FLG) rs2065955 polymorphism and susceptibility to Epstein-Barr virus(EBV)-associated gastric carcinoma(EBVa GC) and EBV-negative gastric carcinoma(EBVn GC) was investigated in Shandong Province,China.We detected the FLG rs2065955 genotype and allele distribution by using PCR and restriction fragment length polymorphism(RFLP) in 64 EBVa GC,82 EBVn GC,and 111 normal control samples.Immunohistochemistry was used to detect the level of FLG protein in 35 EBVa GC and 51 EBVn GC tumor tissues.Compared with normal controls,the genotype CC and allele C of FLG rs2065955 showed higher frequency in EBVa GC and EBVn GC.There was no significant difference between EBVa GC and EBVn GC in allele distribution of FLG rs2065955,but the genotype CC was found more frequently in EBVa GC than in EBVn GC.The risk of developing either EBVa GC or EBVn GC in genotype CC was higher than in other genotypes.Furthermore,genotype CC of FLG rs2065955 may contribute more to the risk of developing EBVa GC than EBVn GC.There was no significant difference in the expression level of FLG protein between EBVa GC and EBVn GC.In conclusion,the FLG rs2065955 polymorphism was significantly related to gastric carcinoma.Allele C of FLG rs2065955 could be a risk factor for EBVa GC or EBVn GC,while genotype CC of FLG rs2065955 was especially associated with EBVa GC.     

Proteomic Analysis of Horseweed (Conyza canadensis) Subjected to Caprylic Acid Stress

Caprylic acid (CAP) is anticipated to be a potential biocontrol herbicide in the control of weeds, however the molecular mechanism of how CAP affects weeds is poorly understood. Here, the physiological and biochemical (protein‐level) changes in horseweed (Conyza canadensis L.) are studied under CAP treatment, with infrared gas analyzer and label‐free quantitative proteomics methods. In total, 112 differentially‐accumulated proteins (DAPs) (>1.5 fold change, p < 0.05) are present between treated horseweed and control samples, with 46 up‐regulated and 66 down‐regulated proteins. These DAPs are involved in 28 biochemical pathways, including photosynthesis pathways. In particular, six photosynthesis proteins show significant abundance changes in the CAP‐treated horseweed. The qRT‐PCR results confirm three of the six genes involved in photosynthesis. Moreover, by measuring photosynthesis characteristics, CAP was shown to decrease photosynthetic rate, stomatal conductance, intercellular CO₂ concentration, and the transpiration rate of horseweed. These results suggest that photosystem I is one of the main biological processes involved in the response of horseweed to CAP.     

Molecular Characterization and Expression Analysis of ftr01, ftr42, and ftr58 in Zebrafish (Danio rerio)

Tripartite motif(TRIM) proteins were shown to play an important role in innate antiviral immunity. FinTRIM(ftr) is a new subset of TRIM genes that do not possess obvious orthologs in higher vertebrates. However, little is known about its function. In this study, we used bioinformatic analysis to examine the phylogenetic relationships and conserved domains of zebrafish(Danio rerio) ftr01, ftr42, and ftr58, as well as qualitative real-time PCR to examine their expression patterns in zebrafish embryonic fibroblast(ZF4) cells and zebrafish tissues. Sequence analysis showed that the three finTRIMs are highly conserved, and all contain a RING domain, B-box domain, and SPRY-PRY domain. In addition, ftr42 and ftr58 had one coiled-coil domain(CCD), whereas ftr01 had two CCDs. Tissue expression analysis revealed that the m RNA level of ftr01 was the highest in the liver, whereas those of ftr42 and ftr58 were the highest in the gill; the expression of thesefinTRIMs was clearly upregulated not in the eyes, but in the liver, spleen, kidney, gill, and brain of zebrafish following spring viremia of carp virus(SVCV) infection. Similarly, the expression of these three finTRIM genes also increased in ZF4 cells after SVCV infection. Our study revealed that ftr01, ftr42, and ftr58 may play an important role in antiviral immune responses, and these findings validate the need for more in-depth research on the finTRIM family in the future.