Endogenous growth, decline in social capital and expansion of market activities

We model in an endogenous growth set-up the hypotheses that the expansion of market activities weakens social capital formation, and that firms can invest in formal mechanisms of control and enforcement to substitute for social capital (trust, work ethics, honesty). The model shows that the economy tends to grow faster when it is relatively poorer in social capital and that perpetual growth can be consistent with the progressive erosion of social capital. These results may help reconciling Putnam’s claim that social capital has declined in the U.S. with the satisfactory growth performance of the U.S. economy over the same period.Generalized trust; externalities; marketization; social assets

Endogenous growth, decline in social capital and expansion of market activities

We model in an endogenous growth set-up the hypotheses that the expansion of market activities weakens social capital formation and that firms can invest in formal mechanisms of control and enforcement to substitute for social capital (trust, work ethics, honesty). The model shows that the economy tends to grow faster when it is relatively poorer in social capital and that perpetual growth can be consistent with the progressive erosion of social capital. These results may help to reconcile Putnam's claim that social capital has declined in the U.S. with the satisfactory growth performance of the U.S. over the same period

Buying alone: how americans’ unhappiness turned into the current economic crisis

Recent decades have seen Americans working longer hours at the same time as massive increases in the level of household debt in order to fuel consumption have taken place. Why did household consumption grow so rapidly, especially in the lead up to the Great Recession? Stefano Bartolini, Luigi Bonatti and Francesco Sarracino argue that this rise in consumption can be explained in part by an erosion of environmental and social assets, and an associated fall in people’s well-being and happiness. They write that people have tried to compensate for the decline of these ‘free goods’ by purchasing more and more consumer goods, and on services to protect against risks such as health insurance and private security

Palmitylation of viral membrane glycoproteins takes place after exit from the endoplasmic reticulum

Abstract Palmitylation of vesicular stomatitis virus G and Sindbis virus E1 glycoproteins has been studied in relation to the transport from the endoplasmic reticulum (ER) to the Golgi complex. Incubation of infected cells at 15 degrees C prevents the transport of newly synthesized membrane proteins from the ER to the Golgi (Saraste, J., and Kuismanen, E. (1984) Cell 38, 535-549). In these conditions, also palmitylation of G protein and of E1 glycoprotein is blocked. When the transport is restored by increasing the temperature, palmitylation occurs quickly and is followed by the complete trimming of peripheral mannose residues due to mannosidase I (a putative cis-Golgi function). Immunofluorescence analysis showed that the G glycoprotein accumulated at 15 degrees C in structures distinct from both ER and Golgi. These studies suggest that transport from the ER to the cis-Golgi involves intermediate compartments

Endogenous growth, decline in social capital and expansion of market activities

We model in an endogenous growth set-up the hypotheses that the expansion of market activities weakens social capital formation, and that firms can invest in formal mechanisms of control and enforcement to substitute for social capital (trust, work ethics, honesty). The model shows that the economy tends to grow faster when it is relatively poorer in social capital and that perpetual growth can be consistent with the progressive erosion of social capital. These results may help reconciling Putnam’s claim that social capital has declined in the U.S. with the satisfactory growth performance of the U.S. economy over the same period

Endogenous growth, decline in social capital and expansion of market activities

We model in an endogenous growth set-up the hypotheses that the expansion of market activities weakens social capital formation, and that firms can invest in formal mechanisms of control and enforcement to substitute for social capital (trust, work ethics, honesty). The model shows that the economy tends to grow faster when it is relatively poorer in social capital and that perpetual growth can be consistent with the progressive erosion of social capital. These results may help reconciling Putnam’s claim that social capital has declined in the U.S. with the satisfactory growth performance of the U.S. economy over the same period

QM/Classical Modeling of Surface Enhanced Raman Scattering Based on Atomistic Electromagnetic Models

We present quantum mechanics (QM)/frequency dependent fluctuating charge (QM/ωFQ) and fluctuating dipoles (QM/ωFQFμ) multiscale approaches to model surface-enhanced Raman scattering spectra of molecular systems adsorbed on plasmonic nanostructures. The methods are based on a QM/classical partitioning of the system, where the plasmonic substrate is treated by means of the atomistic electromagnetic models ωFQ and ωFQFμ, which are able to describe in a unique fashion and at the same level of accuracy the plasmonic properties of noble metal nanostructures and graphene-based materials. Such methods are based on classical physics, i.e. Drude conduction theory, classical electrodynamics, and atomistic polarizability to account for interband transitions, by also including an ad-hoc phenomenological correction to describe quantum tunneling. QM/ωFQ and QM/ωFQFμ are thus applied to selected test cases, for which computed results are compared with available experiments, showing the robustness and reliability of both approaches

Biosynthesis and oligosaccharide structure of human CD8 glycoprotein expressed in a rat epithelial cell line.

The biosynthesis, post-translational modifications, and oligosaccharide structure of human CD8 glycoprotein have been studied in transfected rat epithelial cells. These cells synthesized and expressed on the plasma membrane high amounts of CD8 in a homodimeric form stabilized by a disulfide bridge. Three different CD8 forms were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis after metabolic labeling and immunoprecipitation: a newly synthesized, unglycosylated 27-kDa (CD8u), a palmitylated and initially O-glycosylated 29-kDa (CD8i), and the mature, terminally glycosylated 32-34-kDa doublet (CD8m). CD8i is a transient intermediate form between CD8u and CD8m: characterization of carbohydrate moiety of [3H]glucosamine-labeled CD8i showed that it comprises for the vast majority non-elongated O-linked GalNAc closely spaced on the peptide backbone. Structural analysis of oligosaccharides released by mild alkaline borohydride treatment from the [3H]glucosamine-labeled CD8 34-kDa form showed that the neutral tetrasaccharide Gal beta 1,4GlcNAc beta 1,6(Gal beta 1,3)GalNAcOH, and an homologous monosialylated pentasaccharide, predominate; the disialylated NeuAc2,3Gal beta 1,3(NeuAc alpha 2,6) GalNAcOH tetrasaccharide appeared to be poorly present. In the CD8 32-kDa form the neutral tetrasaccharide was by far the prominent O-linked chain, and no disialyloligosaccharides were identified. These results indicate that the maturation of CD8 glycoprotein in transfected rat epithelial cells results in the formation of branched O-linked oligosaccharides and that a higher degree of sialylation is responsible for the production of the heavier 34-kDa form

Regulation of ERGIC-53 gene transcription in response to endoplasmic reticulum stress.

Accumulation of unfolded proteins within the endoplasmic reticulum (ER) activates the unfolded protein response, also known as the ER stress response. We previously demonstrated that ER stress induces transcription of the ER Golgi intermediate compartment protein ERGIC-53. To investigate the molecular events that regulate unfolded protein response-mediated induction of the gene, we have analyzed the transcriptional regulation of ERGIC-53. We found that the ERGIC-53 promoter contains a single cis-acting element that mediates induction of the gene by thapsigargin and other ER stress-causing agents. This ER stress response element proved to retain a novel structure and to be highly conserved in mammalian ERGIC-53 genes. The ER stress response element identified contains a 5'-end CCAAT sequence that constitutively binds NFY/CBF and, 9 nucleotides away, a 3'-end region (5'-CCCTGTTGGCCATC-3') that is equally important for ER stress-mediated induction of the gene. This sequence is the binding site for endogenous YY1 at the 5'-CCCTGTTGG-3' part and for undefined factors at the CCATC 3'-end. ATF6 alpha-YY1, but not XBP1, interacted with the ERGIC-53 regulatory region and activated ERGIC-53 ER stress response element-dependent transcription. A molecular model for the transcriptional regulation of the ERGIC-53 gene is proposed

Ligand of Numb proteins LNX1p80 and LNX2 interactwith the human glycoprotein CD8a and promote itsubiquitylation and endocytosis

E3 ubiquitin ligases give specificity to the ubiquitylation process by selectively binding substrates. Recently, their function has emerged as a crucial modulator of T-cell tolerance and immunity. However, substrates, partners and mechanism of action for most E3 ligases remain largely unknown. In this study, we identified the human T-cell co-receptor CD8 a-chain as binding partner of the ligand of Numb proteins X1 (LNX1p80 isoform) and X2 (LNX2). Both LNX mRNAs were found expressed in T cells purified from human blood, and both proteins interacted with CD8a in human HPB-ALL T cells. By using an in vitro assay and a heterologous expression system we showed that the interaction is mediated by the PDZ (PSD95-DlgA-ZO-1) domains of LNX proteins and the cytosolic C-terminal valine motif of CD8a. Moreover, CD8a redistributed LNX1 or LNX2 from the cytosol to the plasma membrane, whereas, remarkably, LNX1 or LNX2 promoted CD8a ubiquitylation, downregulation from the plasma membrane, transport to the lysosomes, and degradation. Our findings highlight the function of LNX proteins as E3 ligases and suggest a mechanism of regulation for CD8a localization at the plasma membrane by ubiquitylation and endocytosis