Tangential cell migration during layer formation of chick optic tectum

The laminated structure of the optic tectum is formed by radial and tangential cell migration during development. Studies of developing chick optic tectum have revealed two streams of tangential cell migration in the middle and superficial layers, which have distinctive origins, migratory paths, modes of migration, and destinations. We will review the process of the two types of tangential migrations, in order to elucidate their roles in the formation of the optic tectum layers.     

Galanin Signaling in the Brain Regulates Color Pattern Formation in Zebrafish

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A novel Golgi mannosidase inhibitor: Molecular design,synthesis, enzyme inhibition,and inhibition of spheroid formation

Effective chemotherapy for solid cancers is challenging due to a limitation in permeation that prevents anticancer drugs from reaching the center of the tumor, therefore unable to limit cancer cell growth. To circumvent this issue, we planned to apply the drugs directly at the center by first collapsing the outer structure. For this, we focused on cell–cell communication (CCC) between N-glycans and proteins at the tumor cell surface. Mature N-glycans establish CCC; however, CCC is hindered when numerous immature N-glycans are present at the cell surface. Inhibition of Golgi mannosidases (GMs) results in the transport of immature N-glycans to the cell surface. This can be employed to disrupt CCC. Here, we describe the molecular design and synthesis of an improved GM inhibitor with a non-sugar mimic scaffold that was screened from a compound library. The synthesized compounds were tested for enzyme inhibition ability and inhibition of spheroid formation using cell-based methods. Most of the compounds designed and synthesized exhibited GM inhibition at the cellular level. Of those, AR524 had higher inhibitory activity than a known GM inhibitor, kifunensine. Moreover, AR524 inhibited spheroid formation of human malignant cells at low concentration (10 µM), based on the disruption of CCC by GM inhibition.     

Monte Carlo replica‐exchange based ensemble docking of protein conformations

A replica‐exchange Monte Carlo (REMC) ensemble docking approach has been developed that allows efficient exploration of protein–protein docking geometries. In addition to Monte Carlo steps in translation and orientation of binding partners, possible conformational changes upon binding are included based on Monte Carlo selection of protein conformations stored as ordered pregenerated conformational ensembles. The conformational ensembles of each binding partner protein were generated by three different approaches starting from the unbound partner protein structure with a range spanning a root mean square deviation of 1–2.5 Å with respect to the unbound structure. Because MC sampling is performed to select appropriate partner conformations on the fly the approach is not limited by the number of conformations in the ensemble compared to ensemble docking of each conformer pair in ensemble cross docking. Although only a fraction of generated conformers was in closer agreement with the bound structure the REMC ensemble docking approach achieved improved docking results compared to REMC docking with only the unbound partner structures or using docking energy minimization methods. The approach has significant potential for further improvement in combination with more realistic structural ensembles and better docking scoring functions. Proteins 2017; 85:924–937. © 2016 Wiley Periodicals, Inc.     

How to deal with oxygen radicals stemming from mitochondrial fatty acid oxidation

Oxygen radical formation in mitochondria is an incompletely understood attribute of eukaryotic cells. Recently, a kinetic model was proposed, in which the ratio between electrons entering the respiratory chain via FADH₂ or NADH determines radical formation. During glucose breakdown, the ratio is low; during fatty acid breakdown, the ratio is high (the ratio increasing—asymptotically—with fatty acid length to 0.5, when compared with 0.2 for glucose). Thus, fatty acid oxidation would generate higher levels of radical formation. As a result, breakdown of fatty acids, performed without generation of extra FADH₂ in mitochondria, could be beneficial for the cell, especially in the case of long and very long chained ones. This possibly has been a major factor in the evolution of peroxisomes. Increased radical formation, as proposed by the model, can also shed light on the lack of neuronal fatty acid oxidation and tells us about hurdles during early eukaryotic evolution. We specifically focus on extending and discussing the model in light of recent publications and findings.     

A note onStreptomyces No. 6, a chitosanase-producing actinomycete

This communication reports the deposit ofStreptomyces No. 6 in the National Collection of Industrial Bacteria, Aberdeen, AB2 1RY, Scotland, UK (Accession number 13037) and gives some references on its use in lysing cell walls of fungi in the Mucorales leading to protoplast formation. Its use in biotechnological fields is also referred to.     

The Life Cycle of Cryptochlora perforans (Chlorarachniophyta)

Observations on the behaviour of different life cycle stages, gamete fusions, and measurements of nuclear DNA contents in Cryptochlora perforans resulted in a first concept concerning life histories in Chlorarachniophyta: the life cycle of Cr. perforans is diplohaplontic (gamete fusion with karyogamy - mitosis - meiosis - mitosis). In the haploid as well as in the diploid life cycle phases amoeboid and coccoid stages occur. The isomorphic gametes are modified amoebae frequently without filopodia. Only haploid flagellate stages are known representing mito- or meiozoospores. Diploid coccoid stages have a granular cytoplasmic structure and may be somewhat larger than haploid ones. Nevertheless, positive identification of haploid (gametophytic) and diploid (sporophytic) stages is only possible on the basis of nuclear DNA contents.     

Assessment of biofilm formation by Scedosporium apiospermum,S. aurantiacum,S. minutisporum and Lomentospora prolificans

Reported herein is the ability of Scedosporium apiospermum, S. aurantiacum, S. minutisporum and Lomentospora prolificans conidia to adhere, differentiate into hyphae and form biofilms on both polystyrene and lung epithelial cells. To different degrees, all of the fungi adhered to polystyrene after 4 h, with a predominance of those with germinated conidia. Prolonged fungi–polystyrene contact resulted in the formation of a monolayer of intertwined mycelia, which was identified as a typical biofilm structure due to the presence of a viable mycelial biomass, extracellular matrix and enhanced antifungal resistance. Ultrastructural details were revealed by SEM and CLSM, showing the dense compaction of the mycelial biomass and the presence of channels within the organized biofilm. A similar biofilm structure was observed following the co-culture of each fungus with A549 cells, revealing a mycelial trap covering all of the lung epithelial monolayer. Collectively, these results highlight the potential for biofilm formation by these clinically relevant fungal pathogens.     

ELIMÄKI Locus Is Required for Vertical Proprioceptive Response in Birch Trees

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Reciprocal Fitness Feedbacks Promote the Evolution of Mutualistic Cooperation

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