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The neuropeptide elevenin and similar neuropeptide precursors are common in some invertebrates but their physiological function in most species has not been explored. The brown planthopper, Nilaparvata lugens (Stål) has an elevenin-like peptide and a G protein-coupled receptor (GPCR) NlA42 that is homologous to the elevenin receptor of the annelid Platynereis dumerilii . RNA interference (RNAi)-mediated knockdown of either Nl-elevenin or the NlA42 gene resulted in cuticle melanization. Ion transport peptide (ITP) also induces melanization, but unlike ITP, knockdown of NlElevenin and NlA42 did not have any effect on wing expansion or activity after eclosion. In wild condition macropterous individuals show a darker body color when compared with brachypterous individuals, but RNAi experiments suggest that insulin-signaling and Nl-elevenin signaling regulate wing morph and body color independently. NlElevenin was predominantly expressed in the brain while NlA42 was highly expressed in the abdominal integument and brain. A signal Calcium assays using aequorin indicated that NlA42 heterologously expressed in HEK293 cells exhibited responses to synthetic Nl-elevenin peptide from concentrations as low as 10 −9 M. These results suggest that neuropeptide Nl-elevenin is involved in the regulation of melanization through its receptor NlA42. This is the first report of a physiological function for elevenin-like peptides in insects. [ABSTRACT FROM AUTHOR]

• Using NGS data, 49 novel SSR markers for the emu were developed. • Dinucleotide motif (AC) n was the most frequently detected in the emu genome. • A robust parentage test using a 12 SSR marker set was established for Japanese emu. The emu is a useful and new breed of poultry, but their genetic improvement has not advanced yet due to their very recent domestication. Pedigree information is difficult to record because of their complex reproduction system (polyandry). To identify parent-offspring relationships in the emu, parentage test based on polymorphic DNA markers have to be developed. In this study, we isolated more than 25,000 microsatellite (simple sequence repeat, SSR) regions from Next-generation sequencing data via the QDD pipeline and developed 49 SSR markers with polymorphism in the Japanese farmed emu. The dinucleotide motifs, (AC) n , (AT) n and (AG) n , were the most frequently detected and were found on 10,167 (38.55%), 8,114 (30.76%) and 4,796 (18.18%) contigs, respectively. Forty-nine novel SSR markers were characterized in 20 individuals and showed N A ranged from 2 to 12, with an average of 4.2. H E / H O ranged from 0.389/0.071 to 0.702/1.000 with an average of 0.601/0.515. PIC value ranged from 0.059 to 0.886 with an average of 0.528, and 17 of 49 markers showed a higher polymorphism than 0.500. Thirty-four individuals were genotyped using 12 markers, and CERVUS simulations based on genotype showed that parents of all offspring were identified with 0.9995–1.0 probability. Thus, 49 novel SSR markers and a robust method for parentage test for the Japanese emu were developed. [ABSTRACT FROM AUTHOR]

Although intracellular ultrastructures have typically been studied using microscopic techniques, it is difficult to observe ultrastructures at the submicron scale of living cells due to spatial resolution (fluorescence microscopy) or high vacuum environment (electron microscopy). We investigate the nanometer scale intracellular ultrastructures of living CHO cells in various osmolality using small-angle X-ray scattering (SAXS), and especially the structures of ribosomes, DNA double helix, and plasma membranes in-cell environment are observed. Ribosomes expand and contract in response to osmotic pressure, and the inter-ribosomal correlation occurs under isotonic and hyperosmolality. The DNA double helix is not dependent on the osmotic pressure. Under high osmotic pressure, the plasma membrane folds into form a multilamellar structure with a periodic length of about 6 nm. We also study the ultrastructural changes caused by formaldehyde fixation, freezing and heating. [Display omitted] • SAXS reveals nanoscale intracellular ultrastructure of living CHO cells. • Plasma membrane is folded by hyperosmotic pressure to form multilamellar structure. • Multi-scale phase separations are induced or compressed under hyperosmotic pressure. • Real-time temperature-dependent ultrastructural changes are revealed. [ABSTRACT FROM AUTHOR]

The molecular basis of death feigning, an antipredator behavior that has received much attention recently, was analyzed. We compared the gene expression profiles of strains with different behaviors, i.e., different durations of death feigning, in the beetle Tribolium castaneum. Beetles artificially selected for short (S) and long (L) durations of death feigning for many generations were compared thoroughly by RNA sequencing. We identified 518 differentially expressed genes (DEGs) between the strains. The strains also showed divergence in unexpected gene expression regions. As expected from previous physiological studies, genes associated with the metabolic pathways of tyrosine, a precursor of dopamine, were differentially expressed between the S and L strains; these enzyme-encoding genes were expressed at higher levels in the L strain than in the S strain. We also found that several genes associated with insulin signaling were expressed at higher levels in the S strain than in the L strain. Quantitative real-time PCR analysis showed that the relative expression levels of Tchpd (encoding 4-hydroxyphenylpyruvate dioxygenase, Hpd) and Tcnat (encoding N-acetyltransferase, Nat) were significantly higher in the L strain than in the S strain, suggesting the influence of these enzymes on the supply of dopamine and duration of death feigning. [ABSTRACT FROM AUTHOR]

The rheological and morphological characteristics of Ca-crosslinked alginate hydrogels with two different M/G ratios, α-L-guluronate (G)-rich and β-D-mannuronate (M)-rich, each with one alginic acid concentration, were investigated. It was found that the stiffness and elasticity of alginate hydrogels are derived from the thickness and density of the fibril network structures. In aqueous alginate solution, ball-like aggregates of alginates are present. Time-resolved small-angle X-ray scattering and time-domain nuclear magnetic resonance measurements suggest that the disaggregation of alginate aggregates and loose fibrillation occur in the early stage of the sol-gel transition. After these induction stage, direct gelation is finally caused by the formation of the egg-box junction. G-rich alginate hydrogel has a higher stiffness and a thicker and denser fibril network structure than M-rich alginate hydrogel. The former also exhibits faster and more significant changes in physical properties during the sol-gel transition. [ABSTRACT FROM AUTHOR]

Specific genes quickly transcribed after extracellular stimuli without de novo protein synthesis are known as immediate early genes (IEGs) and are thought to contribute to learning and memory processes in the mature nervous system of vertebrates. A recent study revealed that the homolog of Early growth response protein-1 ( Egr-1 ), which is one of the best-characterized vertebrate IEGs, shared similar properties as a neural activity-dependent gene in the adult brain of insects. With regard to the roles of vertebrate Egr-1 in neural development, the contribution to the development and growth of visual systems has been reported. However, in insects, the expression dynamics of the Egr-1 homologous gene during neural development remains poorly understood. Our expression analysis demonstrated that AmEgr , a honeybee homolog of Egr-1 , was transiently upregulated in the developing brain during the early to mid pupal stages. In situ hybridization and 5-bromo-2’-deoxyuridine (BrdU) immunohistochemistry revealed that AmEgr was mainly expressed in post-mitotic cells in optic lobes, the primary visual center of the insect brain. These findings suggest the evolutionarily conserved role of Egr homologs in the development of visual systems in vertebrates and insects. [ABSTRACT FROM AUTHOR]

Scorpion venom contains a variety of biologically active peptides. Among them, neurotoxins are major components in the venom, but it also contains peptides that show antimicrobial activity. Previously, we identified three insecticidal peptides from the venom of the Liocheles australasiae scorpion, but activities and structures of other venom components remained unknown. In this study, we performed a transcriptome analysis of the venom gland of the scorpion L. australasiae to gain a comprehensive understanding of its venom components. The result shows that potassium channel toxin-like peptides were the most diverse, whereas only a limited number of sodium channel toxin-like peptides were observed. In addition to these neurotoxin-like peptides, many non-disulfide-bridged peptides were identified, suggesting that these components have some critical roles in the L. australasiae venom. In this study, we also isolated a component with antiviral activity against hepatitis C virus using a bioassay-guided fractionation approach. By integrating mass spectrometric and transcriptomic data, we successfully identified LaPLA 2 -1 as an anti-HCV component. LaPLA 2 -1 is a phospholipase A 2 having a heterodimeric structure that is N-glycosylated at the N-terminal region. Since the antiviral activity of LaPLA 2 -1 was inhibited by a PLA 2 inhibitor, the enzymatic activity of LaPLA 2 -1 is likely to be involved in its antiviral activity. Image 1 • Transcriptome analysis of the venom gland of the scorpion Liocheles australasiae was performed. • Among components identified, potassium channel toxin-like peptides were the most diverse. • A component with antiviral activity against hepatitis C virus was isolated using a bioassay-guided fractionation approach. • Mass spectrometric analysis revealed that this component is one of the PLA 2 s with N-glycosylation. [ABSTRACT FROM AUTHOR]

Endocrine cells in the gastrointestinal tract secrete multiple hormones to maintain homeostasis in the body. In the present study, we generated intestinal organoids from the duodenum, jejunum, and ileum of Neurogenin 3 (Ngn3)-EGFP mice and examined how enteroendocrine cells (EECs) within organoid cultures resemble native epithelial cells in the gut. Transcriptome analysis of EGFP-positive cells from Ngn3-EGFP organoids showed gene expression pattern comparable to EECs in vivo. We also compared mRNAs of five major hormones, namely, ghrelin (Ghrl), cholecystokinin (Cck), Gip, secretin (Sct), and glucagon (Gcg) in organoids and small intestine along the longitudinal axis and found that expression patterns of these hormones in organoids were similar to those in native tissues. These findings suggest that an intestinal organoid culture system can be utilized as a suitable model to study enteroendocrine cell functions in vitro. Statistical analysis of genes preferentially expressed in Ngn3+ vs Ngn3- cells derived from intestinal organoids of Ngn3-EGFP mice. [ABSTRACT FROM AUTHOR]

To complete their life cycle, a wide range of parasites must manipulate the behavior of their hosts. 1 This manipulation is a well-known example of the "extended phenotype, 2 " where genes in one organism have phenotypic effects on another organism. Recent studies have explored the parasite genes responsible for such manipulation of host behavior, including the potential molecular mechanisms. 3,4 However, little is known about how parasites have acquired the genes involved in manipulating phylogenetically distinct hosts. 4 In a fascinating example of the extended phenotype, nematomorph parasites have evolved the ability to induce their terrestrial insect hosts to enter bodies of water, where the parasite then reproduces. Here, we comprehensively analyzed nematomorphs and their mantid hosts, focusing on the transcriptomic changes associated with host manipulations and sequence similarity between host and parasite genes to test molecular mimicry. The nematomorph's transcriptome changed during host manipulation, whereas no distinct changes were found in mantids. We then discovered numerous possible host-derived genes in nematomorphs, and these genes were frequently up-regulated during host manipulation. Our findings suggest a possible general role of horizontal gene transfer (HGT) in the molecular mechanisms of host manipulation, as well as in the genome evolution of manipulative parasites. The evidence of HGT between multicellular eukaryotes remains scarce but is increasing and, therefore, elucidating its mechanisms will advance our understanding of the enduring influence of HGT on the evolution of the web of life. • Explored molecular basis of nematomorph-driven water-entry behavior of mantids • Nematomorph transcriptomes were exclusively changed during host manipulation • Numerous possible host-derived horizontal gene transfer (HGT) events were discovered • Candidate HGT genes were frequently up-regulated during host manipulation Mishina et al. study the molecular mechanisms of nematomorph-driven water-entry behavior of mantids, revealing transcriptome changes exclusively in nematomorphs during manipulation. Many possible host-derived genes are identified in nematomorphs that are more frequently up-regulated during manipulation, inferring their roles in the manipulation. [ABSTRACT FROM AUTHOR]

The brown egg 4 (b-4) is a recessive mutant in the silkworm (Bombyx mori), whose egg and adult compound eyes exhibit a reddish-brown color instead of normal purple and black, respectively. By double digest restriction-site associated DNA sequencing (ddRAD-seq) analysis, we narrowed down a region linked to the b-4 phenotype to approximately 1.1 Mb that contains 69 predicted gene models. RNA-seq analysis in a b-4 strain indicated that one of the candidate genes had a different transcription start site, which generates a short open reading frame. We also found that exon skipping was induced in the same gene due to an insertion of a transposable element in other two b-4 mutant strains. This gene encoded a putative amino acid transporter that belongs to the β-group of solute carrier (SLC) family and is orthologous to Drosophila eye color mutant gene, mahogany (mah). Accordingly, we named this gene Bmmah. We performed CRISPR/Cas9-mediated gene knockout targeting Bmmah. Several adult moths in generation 0 (G 0) had totally or partially reddish-brown compound eyes. We also established three Bmmah knockout strains, all of which exhibit reddish-brown eggs and adult compound eyes. Furthermore, eggs from complementation crosses between the b-4 mutants and the Bmmah knockout mutants also exhibited reddish-brown color, which was similar to the b-4 mutant eggs, indicating that Bmmah is responsible for the b-4 phenotypes. [Display omitted] • Responsible region for the brown egg 4 (b-4) mutation was narrowed down by ddRAD-seq. • The gene structure was disrupted in one of the candidate genes, Bombyx mori mahogany (Bmmah), in the b-4 mutant strains. • CRISPR/Cas9-mediated gene knockout and complementation test confirmed that the Bmmah is responsible for the b-4 phenotypes. • The Bmmah encoded a putative amino acid transporter that belongs to the β-group of solute carrier family. • The Bmmah gene is essential for normal colorization of eggs, compound eyes, and ganglions. [ABSTRACT FROM AUTHOR]

Evaluates a navigation system for a mobile robot with a visual sensor using a fish-eye lens. Calculation of the position of the robot on the floor using a gyroscope; Usefulness of the system for indoor vehicles; Effectiveness of the image processing circuits in the system; Improvement of the turning performance of the robot through an algorithm.