SNF4Agamma, the Drosophila AMPK gamma subunit is required for regulation of developmental and stress-induced autophagy

In holometabolous insects including Drosophila melanogaster a wave of autophagy triggered by 20-hydroxyecdysone is observed in the larval tissues during the third larval stage of metamorphosis. We used this model system to study the genetic regulation of autophagy. We performed a genetic screen to select P-element insertions that affect autophagy in the larval fat body. Light and electron microscopy of one of the isolated mutants (l(3)S005042) revealed the absence of autophagic vesicles in their fat body cells during the third larval stage. We show that formation of autophagic vesicles cannot be induced by 20-hydroxyecdysone in the tissues of mutant flies and represent evidence demonstrating that the failure to form autophagic vesicles is due to the insertion of a P-element into the gene coding SNF4Agamma, the Drosophila homologue of the AMPK (AMP-activated protein kinase) gamma subunit. The ability to form autophagic vesicles (wild-type phenotype) can be restored by remobilization of the P-element in the mutant. Silencing of SNF4Agamma by RNAi suppresses autophagic vesicle formation in wild-type flies. We raised an antibody against SNF4Agamma and showed that this gene product is constitutively present in the wild-type larval tissues during postembryonal development. SNF4Agamma is nearly absent from the cells of homozygous mutants. SNF4Agamma translocates into the nuclei of fat body cells at the onset of the wandering stage concurrently with the beginning of the autophagic process. Our results demonstrate that SNF4Agamma has an essential role in the regulation of autophagy in Drosophila larval fat body cells.     

1H, 13C, and 15N resonance assignment of the N-terminal domain of Mason-Pfizer monkey virus capsid protein, CA 1-140

Mason-Pfizer monkey virus (M-PMV) belongs to the family of betaretroviruses characterized by the assembly of immature particles within cytoplasm of infected cells in contrast to other retroviruses (e.g. HIV, RSV) that assemble their immature particles at a plasma membrane. Simultaneously with or shortly after budding a virus-encoded protease is activated and the Gag polyprotein is cleaved into three major structural proteins: matrix (MA), capsid (CA), and nucleocapsid (NC) protein. Mature retroviral CA proteins consist of two independently folded structural domains: N-terminal domain (NTD) and C-terminal dimerization domain (CTD), separated by a flexible linker. As a first step toward the solution structure elucidation, we present nearly complete backbone and side-chain ¹H, ¹⁵N and ¹³C resonance assignment of the M-PMV NTD CA.     

Comparative proteomic analysis of mouse livers from embryo to adult reveals an association with progression of hepatocellular carcinoma

To identify potential oncofetal biomarkers that distinguish hepatocellular carcinoma (HCC) from healthy liver tissues, we compared and analyzed the proteomic profiles of mouse livers at different developmental stages. Fetal (E13.5, E16.5), newborn (NB), postnatal (3-week) and adult (3-month) livers were isolated and profiled by 2-D PAGE. Statistical analysis using linear regression and false discovery rate (FDR) revealed that 361 protein spots showed significant changes. Unsupervised hierarchical tree analysis segregated the proteins into fetal, NB, and postnatal-adult clusters. Distinctive protein markers were identified by MALDI-TOF/MS and the corresponding mRNA profiles were further determined by Q-PCR. Fetal markers (hPCNA, hHSP7C, hHEM6) and postnatal-adult markers (hARGI1, hASSY, hBHMT, hFABPL) were selected for testing against a panel of seven human hepatocyte/HCC cell lines and 59 clinical specimens. The fetal proteins were found to be overexpressed in the metastatic HCC cell lines and the tumor tissues, whereas the postnatal-adult proteins were expressed in non-tumor tissues and normal hepatocytes. This "Ying-Yang" pattern, as orchestrated by distinct fetal and adult markers, is hypothesized to indicate the progressive change of the liver from a growing, less-differentiated organ into a functional metabolic center. Thus, embryogenesis and tumorigenesis share certain oncofetal markers and adult "hepatic" phenotypes are lost in HCC.     

Isolation and cross‐species amplification of microsatellite loci in the freshwater minnow Zacco pachycephalus (Teleostei: Cyprinidae) for diversity and conservation genetic analysis

Asian minnows of the genus Zacco are dominant fish in various freshwater ecosystems. Two species, Zacco pachycephalus and Z. platypus, occur in Taiwan and are favourite targets for local sport anglers. The introduction of Zacco fish into nonindigenous habitats in Taiwan has become a conservation issue. We developed eight polymorphic microsatellites for Z. pachycephalus (average H_E = 0.779) and these microsatellites were applicable to Z. platypus, which showed a comparable polymorphic level (average H_E = 0.784). These loci can be used as genetic markers for identifying conservation units and studying population differentiation for both Zacco species.     

Synergy Management Services Companies: A New Business Model for Industrial Park Operators

The concept of industrial symbiosis (IS) was introduced decades ago and its environmental and economic benefits are well established, but the broad acceptance of IS still faces significant barriers. This article provides a new approach to capture synergies within industrial parks by suggesting a new business model. Building on findings from a survey conducted by the authors and on literature, we first identify potential barriers to low‐carbon synergistic projects. Economic concerns of technically feasible synergies and financial issues turn out to be the largest barriers, because of long payback periods and fluctuating raw material and by‐product market prices. Existing business models do not offer easy ways to overcome or relax these barriers. We therefore introduce the concept of a synergy management services company (SMSCO), a synergy contractor and third‐party financing model, to overcome these barriers. This model shifts the financial risk of the synergistic project from collaborating firms to the SMSCO. We posit that this attribute of the SMSCO model makes it attractive for industrial park operators who seek long‐term solutions to secure future viability of their park.     

Designing of PLA scaffolds for bone tissue replacement fabricated by ordinary commercial 3D printer

Background

The primary objective of Tissue engineering is a regeneration or replacement of tissues or organs damaged by disease, injury, or congenital anomalies. At present, Tissue engineering repairs damaged tissues and organs with artificial supporting structures called scaffolds. These are used for attachment and subsequent growth of appropriate cells. During the cell growth gradual biodegradation of the scaffold occurs and the final product is a new tissue with the desired shape and properties.In recent years, research workplaces are focused on developing scaffold by bio-fabrication techniques to achieve fast, precise and cheap automatic manufacturing of these structures. Most promising techniques seem to be Rapid prototyping due to its high level of precision and controlling. However, this technique is still to solve various issues before it is easily used for scaffold fabrication.In this article we tested printing of clinically applicable scaffolds with use of commercially available devices and materials. Research presented in this article is in general focused on “scaffolding” on a field of bone tissue replacement.

Results

Commercially available 3D printer and Polylactic acid were used to create originally designed and possibly suitable scaffold structures for bone tissue engineering. We tested printing of scaffolds with different geometrical structures. Based on the osteosarcoma cells proliferation experiment and mechanical testing of designed scaffold samples, it will be stated that it is likely not necessary to keep the recommended porosity of the scaffold for bone tissue replacement at about 90%, and it will also be clarified why this fact eliminates mechanical properties issue. Moreover, it is demonstrated that the size of an individual pore could be double the size of the recommended range between 0.2–0.35 mm without affecting the cell proliferation.

Conclusion

Rapid prototyping technique based on Fused deposition modelling was used for the fabrication of designed scaffold structures. All the experiments were performed in order to show how to possibly solve certain limitations and issues that are currently reported by research workplaces on the field of scaffold bio-fabrication. These results should provide new valuable knowledge for further research.

     

Growth‐form and spatiality driving the functional difference of native and alien aquatic plants in Europe

Trait‐based approaches are widely used in community ecology and invasion biology to unravel underlying mechanisms of vegetation dynamics. Although fundamental trade‐offs between specific traits and invasibility are well described among terrestrial plants, little is known about their role and function in aquatic plant species. In this study, we examine the functional differences of aquatic alien and native plants stating that alien and native species differ in selected leaf traits. Our investigation is based on 60 taxa (21 alien and 39 native) collected from 22 freshwater units of Hungarian and Italian lowlands and highlands. Linear mixed models were used to investigate the effects of nativeness on four fundamental traits (leaf area, leaf dry matter content, specific leaf area, and leaf nitrogen content), while the influence of growth‐form, altitude, and site were employed simultaneously. We found significantly higher values of leaf areas and significantly lower values of specific leaf areas for alien species if growth‐form was included in the model as an additional predictor.We showed that the trait‐based approach of autochthony can apply to aquatic environments similar to terrestrial ones, and leaf traits have relevance in explaining aquatic plant ecology whether traits are combined with growth‐forms as a fixed factor. Our results confirm the importance of traits related to competitive ability in the process of aquatic plant invasions. Alien aquatic plants can be characterized as species producing soft leaves faster. We argue that the functional traits of alien aquatic plants are strongly growth‐form dependent. Using the trait‐based approach, we found reliable characteristics of aquatic plants related to species invasions, which might be used, for example, in conservation management.     

Developmental regulation of 14-3-3 ϵ isoform in rat heart

Human heart cDNA sequencing yielded a cDNA clone that is similar in DNA and amino acid sequences to that of mouse 14-3-3 ϵ isoform. The 6xHis-tagged H1433ϵ recombinant protein was expressed in Escherichia coli and its size was approximately 30 kDa. From Northern blot results with human multiple tissues, human skeletal muscle was found to have the highest level of h1433ϵ mRNA expression, whereas Northern blots of human cancer cell lines detected the highest mRNA level of h1433ϵ in colorectal adenocarcinoma SW480. The protein expression level of h1433ϵ and Raf-1 is found to be regulated coordinately during rat heart development, and their protein expression was highest from 14.5 to 16.5 days postcoitum. J. Cell. Biochem. 68:195–199, 1998. © 1998 Wiley-Liss, Inc.