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Nucleoporins build the nuclear pore complex (NPC), which, as sole gate for nuclear-cytoplasmic exchange, is of outmost importance for normal cell function. Defects in the process of nucleocytoplasmic transport or in its machinery have been frequently described in human diseases, such as cancer and neurodegenerative disorders, but only in a few cases of developmental disorders. Here we report biallelic mutations in the nucleoporin NUP88 as a novel cause of lethal fetal akinesia deformation sequence (FADS) in two families. FADS comprises a spectrum of clinically and genetically heterogeneous disorders with congenital malformations related to impaired fetal movement. We show that genetic disruption of nup88 in zebrafish results in pleiotropic developmental defects reminiscent of those seen in affected human fetuses, including locomotor defects as well as defects at neuromuscular junctions. Phenotypic alterations become visible at distinct developmental stages, both in affected human fetuses and in zebrafish, whereas early stages of development are apparently normal. The zebrafish phenotypes caused by nup88 deficiency are rescued by expressing wild-type Nup88 but not the disease-linked mutant forms of Nup88. Furthermore, using human and mouse cell lines as well as immunohistochemistry on fetal muscle tissue, we demonstrate that NUP88 depletion affects rapsyn, a key regulator of the muscle nicotinic acetylcholine receptor at the neuromuscular junction. Together, our studies provide the first characterization of NUP88 in vertebrate development, expand our understanding of the molecular events causing FADS, and suggest that variants in NUP88 should be investigated in cases of FADS., Competing Interests: The authors have declared that no competing interests exist.

Syntheses of novel semi-orthogonally protected CycloTriVeratrilene (CTV) analogues with enhanced water solubility, that is 3 and 4, derived from the previously described CTV scaffold derivative 2 are described here. These scaffolds 2-4 enabled a sequential introduction of three different complementarity determining region (CDR) mimics via Cu(i)-catalysed azide-alkyne cycloaddition towards medium-sized protein mimics denoted as "synthetic antibodies". The highly optimised sequential introduction enabled selective attachment of three different CDR mimics in a one-pot fashion. This approach of obtaining synthetic antibodies, demonstrated by the synthesis of paratope mimics of monoclonal antibody infliximab (Remicade®), provided a facile access to a range of (highly) pre-organised molecules bearing three different (cyclic) peptide segments and may find a wide range of applications in the field of protein-protein interaction disruptors as well as in the development of synthetic vaccines or lectin mimics. The prepared synthetic antibodies were tested for their affinity towards tumour necrosis factor alpha using surface plasmon resonance and synthetic antibodies with micromolar affinities were uncovered.

A new category of phosphonium based cationic amphiphilic peptides has been developed and evaluated as potential antimicrobial peptides and cell penetrating peptides. The required building blocks were conveniently accessible from cysteine and could be applied in a solid phase peptide synthesis protocol for incorporation into peptide sequences. Evaluation of the antimicrobial properties and cellular toxicity of these phosphonium based peptides showed that these "soft" cationic side-chain containing peptides have poor antimicrobial properties and most of them were virtually non toxic (on HEK cells tested at 256 and 512 μM) and non-haemolytic (on horse erythrocytes tested at 512 μM), hinting at an interesting potential application as cell penetrating peptides. This possibility was evaluated using fluorescent peptide derivatives and showed that these phosphonium based peptide derivatives were capable of entering HEK cells and depending on the sequence confined to specific cellular areas.

Over the past few decades, it is increasingly evident that nucleoporins are multi-functional proteins that are not only pivotal for the formation of the nuclear pore complex. They also have key roles in mitosis, gene expression, development and disease. In this review, the versatility and functions of nucleoporins outside the NPC will be discussed., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Herein, we report a hybrid polyoxometalate organic-inorganic compound, Na 2 [(HGMP) 2 Mo 5 O 15 ]⋅7 H 2 O (1; where GMP=guanosine monophosphate), which spontaneously assembles into a structure with dimensions that are strikingly similar to those of the naturally occurring left-handed Z-form of DNA. The helical parameters in the crystal structure of the new compound, such as rise per turn and helical twist per dimer, are nearly identical to this DNA conformation, allowing a close comparison of the two structures. Solution circular dichroism studies show that compound 1 also forms extended secondary structures in solution. Gel electrophoresis studies demonstrate the formation of non-covalent adducts with natural plasmids. Thus we show a route by which simple hybrid inorganic-organic monomers, such as compound 1, can spontaneously assemble into a double helix without the need for a covalently connected linear sequence of nucleic acid base pairs., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Three dimensional (3D) printing is actively sought after in recent years as a promising novel technology to construct complex objects, which scope spans from nano- to over millimeter scale. Previously we utilized Fused deposition modeling (FDM)-based 3D printer to construct complex 3D chemical fluidic systems, and here we demonstrate the construction of 3D milli-fluidic structures for programmable liquid handling and control of biological samples. Basic fluidic operation devices, such as water-in-oil (W/O) droplet generators for producing compartmentalized mono-disperse droplets, sensor-integrated chamber for online monitoring of cellular growth, are presented. In addition, chemical surface treatment techniques are used to construct valve-based flow selector for liquid flow control and inter-connectable modular devices for networking fluidic parts. As such this work paves the way for complex operations, such as mixing, flow control, and monitoring of reaction / cell culture progress can be carried out by constructing both passive and active components in 3D printed structures, which designs can be shared online so that anyone with 3D printers can reproduce them by themselves.

Background: The human branched chain aminotransferases (hBCATm, mitochondrial and hBCATc, cytosolic) are major contributors to brain glutamate production. This excitatory neurotransmitter is thought to contribute to neurotoxicity in neurodegenerative conditions such as Alzheimer's disease (AD) but the expression of hBCAT in this disease has not previously been investigated., Objective: The objective of investigating hBCAT expression is to gain insight into potential metabolic pathways that may be dysregulated in AD brain, which would contribute to glutamate toxicity., Methods: Western blot analysis and immunohistochemistry were used to determine the expression and localization of hBCAT in postmortem frontal and temporal cortex from AD and matched control brains., Results: Western blot analysis demonstrated a significant regional increase in hBCATc expression in the hippocampus (↑ 36%; p-values of 0.012), with an increase of ↑ 160% reported for hBCATm in the frontal and temporal cortex (p-values = 4.22 × 10⁻⁴ and 2.79 × 10⁻⁵, respectively) in AD relative to matched controls, with evidence of post-translational modifications to hBCATm, more prominent in AD samples. Using immunohistochemistry, a significant increase in immunopositive labelling of hBCATc was observed in the CA1 and CA4 region of the hippocampus (p-values = 0.011 and 0.026, respectively) correlating with western blot analysis. Moreover, the level of hBCATm in the frontal and temporal cortex correlated significantly with disease severity, as indicated by Braak staging (p-values = 5.63 × 10⁻⁶ and 9.29 × 10⁻⁵, respectively)., Conclusion: The expression of the hBCAT proteins is significantly elevated in AD brain. This may modulate glutamate production and toxicity, and thereby play a role in the pathogenesis of the disease.

Aims: The human branched-chain aminotransferase proteins (hBCATm and hBCATc) are regulated through oxidation and S-nitrosation. However, it remains unknown whether they share common redox characteristics to enzymes such as protein disulfide isomerase (PDI) in terms of regulating cellular repair and protein misfolding., Results: Here, similar to PDI, the hBCAT proteins showed dithiol-disulfide isomerase activity that was mediated through an S-glutathionylated mechanism. Site-directed mutagenesis of the active thiols of the CXXC motif demonstrates that they are fundamental to optimal protein folding. Far Western analysis indicated that both hBCAT proteins can associate with PDI. Co-immunoprecipitation studies demonstrated that hBCATm directly binds to PDI in IMR-32 cells and the human brain. Electron and confocal microscopy validated the expression of PDI in mitochondria (using Mia40 as a mitochondrial control), where both PDI and Mia40 were found to be co-localized with hBCATm. Under conditions of oxidative stress, this interaction is decreased, suggesting that the proposed chaperone role for hBCATm may be perturbed. Moreover, immunohistochemistry studies show that PDI and hBCAT are expressed in the same neuronal and endothelial cells of the vasculature of the human brain, supporting a physiological role for this binding., Innovation: This study identifies a novel redox role for hBCAT and confirms that hBCATm differentially binds to PDI under cellular stress., Conclusion: These studies indicate that hBCAT may play a role in the stress response of the cell as a novel redox chaperone, which, if compromised, may result in protein misfolding, creating aggregates as a key feature in neurodegenerative conditions such as Alzheimer's disease.

The bacteriophage vB_SenS-Ent1 (Ent1) is a member of the family Siphoviridae of tailed bacteriophages and infects a broad range of serovars of the enteric pathogen Salmonella enterica. The virion particle is composed of an icosahedral head 64 nm in diameter and a flexible, non-contractile tail of 116 × 8.5 nm possessing terminal fibres. The adsorption rate constant at 37 °C is 6.73 × 10(-9) ml min(-1). Latent and eclipse periods are 25 and 20 min, respectively, and the burst size is 35 progeny particles per cell after 35 min at 37 °C. Sequencing revealed a circularly permuted, 42 391 bp dsDNA genome containing 58 ORFs organized into four major transcriptional units. Comparisons with the genome sequences of other bacteriophages revealed a high level of nucleotide sequence identity and shared orthologous proteins with the Salmonella phages SETP3, SE2 and KS7 (SS3e) and the Escherichia phages K1G, K1H, K1ind1 and K1ind3.