Restricted Morphological and Behavioral Abnormalities following Ablation of β-Actin in the Brain

The local translation of β-actin is one mechanism proposed to regulate spatially-restricted actin polymerization crucial for nearly all aspects of neuronal development and function. However, the physiological significance of localized β-actin translation in neurons has not yet been demonstrated in vivo. To investigate the role of β-actin in the mammalian central nervous system (CNS), we characterized brain structure and function in a CNS-specific β-actin knock-out mouse (CNS-ActbKO). β-actin was rapidly ablated in the embryonic mouse brain, but total actin levels were maintained through upregulation of other actin isoforms during development. CNS-ActbKO mice exhibited partial perinatal lethality while survivors presented with surprisingly restricted histological abnormalities localized to the hippocampus and cerebellum. These tissue morphology defects correlated with profound hyperactivity as well as cognitive and maternal behavior impairments. Finally, we also identified localized defects in axonal crossing of the corpus callosum in CNS-ActbKO mice. These restricted defects occurred despite the fact that primary neurons lacking β-actin in culture were morphologically normal. Altogether, we identified novel roles for β-actin in promoting complex CNS tissue architecture while also demonstrating that distinct functions for the ubiquitously expressed β-actin are surprisingly restricted in vivo

A mechanically active heterotypic E-cadherin/N-cadherin adhesion enables fibroblasts to drive cancer cell invasion

Cancer-associated fibroblasts (CAFs) promote tumour invasion and metastasis. We show that CAFs exert a physical force on cancer cells that enables their collective invasion. Force transmission is mediated by a heterophilic adhesion involving N-cadherin at the CAF membrane and E-cadherin at the cancer cell membrane. This adhesion is mechanically active; when subjected to force it triggers β-catenin recruitment and adhesion reinforcement dependent on α-catenin/vinculin interaction. Impairment of E-cadherin/N-cadherin adhesion abrogates the ability of CAFs to guide collective cell migration and blocks cancer cell invasion. N-cadherin also mediates repolarization of the CAFs away from the cancer cells. In parallel, nectins and afadin are recruited to the cancer cell/CAF interface and CAF repolarization is afadin dependent. Heterotypic junctions between CAFs and cancer cells are observed in patient-derived material. Together, our findings show that a mechanically active heterophilic adhesion between CAFs and cancer cells enables cooperative tumour invasion

Characterization of a furan aldehyde-tolerant β-xylosidase/α-arabinosidase obtained through a synthetic metagenomics approach

Aims The aim of the study was to characterize 10 hemicellulolytic enzymes obtained from a wheat straw-degrading microbial consortium. Methods and Results Based on previous metagenomics analyses, 10 glycosyl hydrolases were selected, codon‐optimized, synthetized, cloned and expressed in Escherichia coli. Nine of the overexpressed recombinant proteins accumulated in cellular inclusion bodies, whereas one, a 37·5‐kDa protein encoded by gene xylM1989, was found in the soluble fractions. The resulting protein, denoted XylM1989, showed β‐xylosidase and α‐arabinosidase activities. It fell in the GH43 family and resembled a Sphingobacterium sp. protein. The XylM1989 showed optimum activity at 20°C and pH 8·0. Interestingly, it kept approximately 80% of its β‐xylosidase activity in the presence of 0·5% (w/v) furfural and 0·1% (w/v) 5‐hydroxymethylfurfural. Additionally, the presence of Ca2+, Mg2+ and Mn2+ ions increased the enzymatic activity and conferred complete tolerance to 500 mmol l−1 of xylose. Protein XylM1989 is also able to release sugars from complex polysaccharides Conclusion We report the characterization of a novel bifunctional hemicellulolytic enzyme obtained through a targeted synthetic metagenomics approach. Significance and Impact of the Study The properties of XylM1989 turn this protein into a promising enzyme that could be useful for the efficient saccharification of plant biomass

Hybrid solar cell based on blending of organic and inorganic materials--An overview

In recent years, increasing efficiency in organic solar cells is due to the bulk heterojunction concept. Hybrid solar cell (HSC) based bulk heterojunction is flourishing in the field of solar cell. This device is the combination of inorganic and organic materials. The efficacy of the power conversion efficiency has reached above 5% by following this combination method. This review provides general introduction, principle, working and characterization in the HSC involving the blend of organic/inorganic material as active layer. Different material combinations of the active layer and their performance are tabulated for better understanding of the HSC. This review ensures total compliance by discussing the fabrication technologies in terms of the HSC concept.Bulk heterojunction Organic/inorganic hybrid Nanomaterials Active layer Power conversion efficiency

Plant-based alkaloids inhibit corrosion of marine alloys

The term microbiologically induced corrosion (MIC) appears to be very closely related to the composition of the bio-film which harbours the micro-organism. Formation of an initial slimy layer on immersed metallic substrated is the rate-controlling parameter of bio-fouling, as uninterrupted undesirable growth of bio-films occurs over this layer. To contain this bio-film problem, formation of an adherent layer of toxic and inhibited corrosion product, that interacts with biofilm, could be exploited. Deals with the preliminary interactions of a few copper-based alloys, with mildly toxic alkaloid class-inhibitive compounds, in a simulated marine environment. It is assumed that the toxic and inhibited corrosion product and bio-film interaction layer will interfere with the formation fo the initial slimy cover on the immersed surface responsible for bio-fouling. It is seen that these alkaloid compounds exert a limited response on the inhibition of copper-based alloys, like monel. Brucine appears to be a more effective inhibitor for the monel surface. Pre-oxidation of the uninhibited brass surface and also post-oxidation of the inhibited surface appear to consolidate the corrosion product bio-film inhibitor interation layers, indicating the compatibility of these alkaloid compounds to the probable thermal strains to be encountered in engineering services. This indicates the poosibility of using these compounds in heat transfer devices, like heat exchangers, where seawater is used as coolan