The inositol phosphatase MTMR4 is a novel target of the ubiquitin ligase Nedd4

The inositol phosphatase, MTMR4 (myotubularin-related protein 4), was identified as a novel interactor of the ubiquitin ligase Nedd4 (neural-precursor-cell-expressed developmentally down-regulated 4). hMTMR4 (human MTMR4) and Nedd4 co-immunoprecipitated and co-localized to late endosomes. The PY (Pro-Tyr) motif of hMTMR4 binds to WW (Trp-Trp) domains of hNedd4. MTMR4 expression was decreased in atrophying muscle, whereas Nedd4 expression was increased and hMTMR4 was ubiquitinated by hNedd4, suggesting that this novel interaction may underlie the biological process of muscle breakdown

Les terres agricoles face à l’urbanisation

La perte de terres agricoles liées à l’urbanisation constitue l’une des facettes de la consommation des terres. Commencé dans les années 1970, ce phénomène — essentiellement dû à l’étalement urbain — prend des proportions jusque-là inégalées. Les conséquences de ces processus d’artificialisation sont multiples et portent à la fois sur la production et sur la sécurité alimentaire ainsi que sur la perte de biodiversité. Ces processus interrogent aussi les formes de solidarité territoriale entre les villes et les espaces péri-urbains et ruraux. Issu d’une collaboration scientifique lancée au début des années 2010 entre l’Université de technologie de Sydney (University of Technology Sydney, UTS) et l’Institut national de recherche en sciences et technologies pour l’environnement et l’agriculture (Irstea), cet ouvrage aborde des points clés de la problématique de la consommation des terres en se focalisant sur les terres agricoles en France et en Australie. Plutôt que d’offrir une analyse comparative approfondie de la planification des terres agricoles périurbaines entre les deux pays, il propose une exploration des « boîtes à outils » de l’ingénierie territoriale développées et mobilisées pour faire face à l’enjeu de la perte de terres agricoles liée à l’urbanisation. Il offre également un « arrêt sur image » dans un panorama de champs de recherche en pleine évolution, autant du point de vue théorique que méthodologique

Basic science232. Certolizumab pegol prevents pro-inflammatory alterations in endothelial cell function

Background: Cardiovascular disease is a major comorbidity of rheumatoid arthritis (RA) and a leading cause of death. Chronic systemic inflammation involving tumour necrosis factor alpha (TNF) could contribute to endothelial activation and atherogenesis. A number of anti-TNF therapies are in current use for the treatment of RA, including certolizumab pegol (CZP), (Cimzia ®; UCB, Belgium). Anti-TNF therapy has been associated with reduced clinical cardiovascular disease risk and ameliorated vascular function in RA patients. However, the specific effects of TNF inhibitors on endothelial cell function are largely unknown. Our aim was to investigate the mechanisms underpinning CZP effects on TNF-activated human endothelial cells. Methods: Human aortic endothelial cells (HAoECs) were cultured in vitro and exposed to a) TNF alone, b) TNF plus CZP, or c) neither agent. Microarray analysis was used to examine the transcriptional profile of cells treated for 6 hrs and quantitative polymerase chain reaction (qPCR) analysed gene expression at 1, 3, 6 and 24 hrs. NF-κB localization and IκB degradation were investigated using immunocytochemistry, high content analysis and western blotting. Flow cytometry was conducted to detect microparticle release from HAoECs. Results: Transcriptional profiling revealed that while TNF alone had strong effects on endothelial gene expression, TNF and CZP in combination produced a global gene expression pattern similar to untreated control. The two most highly up-regulated genes in response to TNF treatment were adhesion molecules E-selectin and VCAM-1 (q 0.2 compared to control; p > 0.05 compared to TNF alone). The NF-κB pathway was confirmed as a downstream target of TNF-induced HAoEC activation, via nuclear translocation of NF-κB and degradation of IκB, effects which were abolished by treatment with CZP. In addition, flow cytometry detected an increased production of endothelial microparticles in TNF-activated HAoECs, which was prevented by treatment with CZP. Conclusions: We have found at a cellular level that a clinically available TNF inhibitor, CZP reduces the expression of adhesion molecule expression, and prevents TNF-induced activation of the NF-κB pathway. Furthermore, CZP prevents the production of microparticles by activated endothelial cells. This could be central to the prevention of inflammatory environments underlying these conditions and measurement of microparticles has potential as a novel prognostic marker for future cardiovascular events in this patient group. Disclosure statement: Y.A. received a research grant from UCB. I.B. received a research grant from UCB. S.H. received a research grant from UCB. All other authors have declared no conflicts of interes

A role for the C2 domain of the ubiquitin-protein ligase Nedd4

grantor: University of TorontoN_eural precursor cell-e_xpressed d_evelopmentally d_ownregulated 4 (Nedd4) is a ubiquitin-protein ligase that has an N-terminal c_onserved region 2_ of PKC (C2) domain, three or four WW domains and a C-terminal h_omolgous to E_6-AP C_-t_erminus (HECT) domain which possesses ubiquitin ligase activity of the third enzyme of the ubiquitination cascade (E3). Nedd4 was found to bind to the epithelial Na+ channel (ENaC), via its WW domains, and to be an important regulator of ENaC stability and function. C2 domains are small (~130 amino acid) Ca2+- and lipid-binding domains that are found in a number of signalling molecules and many have been shown to mediate Ca2+-dependent membrane/protein association. The focus of this work was to determine a role for the C2 domain of Nedd4 in the functioning of this enzyme. It was found that Nedd4 displays a Ca 2+-dependent membrane association, and was demonstrated that this phenomenon is due to the action of the C2 domain. In particular, the C2 domain mediates the redistribution of cytosolic Nedd4 to the apical region of polarized epithelia in response to increased cytosolic Ca2+ concentrations. This preference for the apical region may be mediated by an association of the C2 domain with the apically targeted molecule annexin XIIIb. The C2 domain interacts with annexin XIIIb in a Ca2+-dependent manner and co-localizes with it in cells and in isolated apical rafts in a Ca 2+-dependent fashion. When annexin XIIIb expression is stimulated using an inducible system, it targets Nedd4 to the plasma membrane in response to increased cytosolic Ca2+. In the absence of annexin XIIIb overexpression, Nedd4 remains in the cytosol. A novel interaction between the Nedd4-C2 domain and the SH2 domain of Grb10 was characterized, which may serve to target Nedd4 to the IGF-I receptor, a potential substrate, within the cell. This interaction is non-phosphotyrosine-dependent and non-Ca2+-dependent as well. We have shown that the IGF-I receptor is ubiquitinated in cells, which may be the ultimate consequence of the C2 association with SH2-Grb10. Thus, the study of the role of the C2 domain of Nedd4 has provided evidence that this domain is serving to target Nedd4 to distinct locations within the cell, where it can interact with its substrates. This specialized distribution is mediated via specific protein-protein and protein-lipid interactions. The work on the underlying mechanisms of Nedd4 function has provided an insight into the more general issues of regulation of protein stability and cellular functioning.Ph.D

Recognition of problem drinking among young adult prisoners

Alcohol is a preventable cause of illness, offending and other adversities worldwide. Prisoners are especially vulnerable. The aim of this study was to test the hypotheses that younger adult male prisoners are more likely to be hazardous drinkers than their older peers, but less likely to recognize this. The study cohort comprised 100 male prisoners aged 18–20 years and 157 aged 21 and over, who were interviewed and completed standard alcohol and drug questionnaires just after reception into prison. It was found that youngermen were significantly more likely to be hazardous drinkers than their older peers but less likely to recognise this, even at scores on theAlcohol UseDisorders IdentificationTest (AUDIT) indicating dependency. They were also less likely to experience withdrawal symptoms, the main factor associated with problem drinking recognition at any age. Younger prisoners were less likely to be depressed, more likely to rate their social support as good and less likely to be dependent drug users.We conclude that reliance on younger prisoners to recognise their hazardous drinking would identify about one-fifth of them. With a lower likelihood of withdrawal symptoms than older men, they are probably still metabolizing alcoholmore effectively. Given their similarities to older prisoners in terms of any previous imprisonment and likely personality disorder, formal screening for hazardous drinkingmight prevent decline into problem drug use, depression, reoffending, re-imprisonment, and social disconnection. Copyright#2012 JohnWiley & Sons, Ltd