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The question of aesthetic value remains a source of tension within diverse film education environments. While film-makers and audiences have visceral experiences of the value of cinema, these experiences are troubled by a contemporary film studies that tends to adopt a more relativist approach, suggesting that the experience of value is reflective of sociocultural subjectivity. Speaking from two different perspectives, Alan Bernstein and Andrew Burn explore the role of value in film education, and film culture more widely, in 2019. While Bernstein argues for a reinstatement of value as a fundamental aspect of how film is experienced and understood in educational contexts and beyond, Burn contextualizes questions of value within a wider framework of semiotic and aesthetic theory, arguing for a multimodal approach that takes into account the multifaceted nature of film.

After PhD studies at the University of Toronto, and postdoctoral work in London, Alan worked at the Ontario Cancer Institute and then the Samuel Lunenfeld Research Institute (eventually as Director of Research). As inaugural president of the Canadian Institutes of Health Research (CIHR; 2000–2007), he led the transformation of health research in Canada and an almost tripling of the budget for health research. He then was named executive director of the Global HIV Vaccine Enterprise (2008–2012). Since 2012, Alan has been president of CIFAR, Canada’s global research institute, where he has led major initiatives to increase CIFAR’s programs of research and global impact, and launched new programs to nurture the world’s next generation of researchers. Author of 250 scientific and 50 op-ed and lay publications, Alan has received numerous awards and honors, including induction into the Orders of Canada and Ontario, honorary degrees, the Gairdner Wightman Award, induction into the Canadian Medical Hall of Fame and the Henry Friesen International Prize.

Launch a global clean-energy initiative to set priorities that galvanize researchers to deliver breakthroughs, write Alan Bernstein and colleagues.

The protooncogene Vav functions as a GDP/GTP exchange factor (GEF) for Rho-like small GTPases involved in cytoskeletal reorganization and cytokine production in T cells. Gene-targeted mice lacking Vav have a severe defect in positive and negative selection of T cell antigen receptor transgenic thymocytes in vivo, and vav−/− thymocytes are completely resistant to peptide-specific and anti-CD3/anti-CD28–mediated apoptosis. Vav acts upstream of mitochondrial pore opening and caspase activation. Biochemically, Vav regulates peptide-specific Ca2+ mobilization and actin polymerization. Peptide-specific cell death was blocked both by cytochalasin D inhibition of actin polymerization and by inhibition of protein kinase C (PKC). Activation of PKC with phorbol ester restored peptide-specific apoptosis in vav−/− thymocytes. Vav was found to bind constitutively to PKC-θ in thymocytes. Our results indicate that peptide-triggered thymocyte apoptosis is mediated via Vav activation, changes in the actin cytoskeleton, and subsequent activation of a PKC isoform.

During Nurses Week 2008, the Department of Veterans Affairs (VA) Office of Nursing Services (ONS) launched an innovative campaign to increase specialty certification for its nursing workforce that resulted in a one-of-a-kind national initiative. The initiative "Let's Get Certified," currently in its third year of implementation with Phase III of the campaign, has raised the awareness of the benefits of specialty certification among the VA nursing staff. This movement has yielded a more highly educated and competent workforce, improved nurse satisfaction, and promoted quality healthcare to veterans. In early 2008 the idea for the campaign was presented to the ONS Director of Workforce Development and resulted in a nursing work group representing the 45,000 VA nurses throughout the country who provided valuable input into the development of the initial campaign.

An important meeting titled “Defining the Objectives of the AIDS Vaccine Asian Network (AVAN)” was held 22–24 February 2009, in Beijing. This report describes the outcomes of this meeting. The meeting was jointly organised by the World Health Organization (WHO), the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the Global HIV Vaccine Enterprise (GHVE) Regional Consultation on Expanding AIDS Vaccine Research and Development Capacity in Asia. Sixty-eight participants (Supplementary Digital Content 1) and observers gathered together from 16 countries including Australia, Cambodia, China, France, India, Indonesia, Japan, the Netherlands, the Philippines, the Russian Federation, Singapore, Sweden, Switzerland, Thailand, the United States of America and Viet Nam. The meeting was highly relevant for the Asian region at a time when the HIV epidemic is still rampant despite concerted efforts by governments, communities, scientists and key stakeholders to stem its impact and advance. A great deal of work has been undertaken towards an AIDS vaccine over the past 15 years and the region has the essential assets to move the agenda forward. Genesis of the 2009 Beijing meeting In 1998, the first Asian meeting specifically devoted to AIDS vaccine research and development was convened by WHO-UNAIDS and the Japanese National Institute of Infectious Diseases (NIID) in Tokyo, Japan. In 2006, the regional strategy concept was revisited at the first WHO-UNAIDS regional consultation, Expanding Capacity and Accelerating AIDS Vaccine Development in Asia, hosted and co-organized by the University of Hokkaido, Sapporo, Japan. The 7 recommendations of the 2006 Sapporo meeting were to: First, create forums to facilitate interactions between funders and discuss funding opportunities, funding streams and funder capabilities. Second, facilitate linkages between research and development (R&D), innovation and discovery, in particular in emerging countries with strong innovation capacity, such as China, India and Thailand, and clinical trial capacity and production. Third, provide a forum for coordination of regional expertise, capacity building, and technical assistance. Fourth, promote advocacy and communication support for region-specific strategies. Fifth, contribute to and promote the implementation of the Scientific Strategic Plan of the GHVE. Sixth, prepare for future deployment of a vaccine by discussing regional approaches to ensure access, delivery capacity, demand estimates, epidemiology, vaccine characteristics, and strategies for delivery. Seventh, create a regional harmonization or regional authority for regulatory interactions, including regional licensure review and regional ethics committees with an initial ‘core’ working group. To effectively implement and further facilitate the recommendation to develop an ongoing forum for coordination of regional expertise, capacity building and technical assistance, the establishment of AVAN was proposed. In February 2009, the Chinese AIDS Vaccine Initiative (CAVI), GHVE and WHO-UNAIDS convened a follow-up meeting in Beijing, China to speed up implementation of recommendations of the Sapporo consultation.

Neural stem cells (NSCs) have attracted considerable attention as a potential source of cells for therapeutic treatment of impaired areas of the central nervous system. However, efficient and clinically feasible strategies for expansion of the endogenous NSC pool are currently unavailable. In this study, we demonstrate that mood stabilizing drugs, which are used to treat patients with bipolar disorder, enhance the self-renewal capability of mouse NSCs in vitro and that this enhancement is achieved at therapeutically relevant concentrations in the cerebrospinal fluid. The pharmacological effects are mediated by the activation of Notch signaling in the NSC. Treatment with mood stabilizers increased an active form of Notch receptor and upregulated its target genes in neural stem/progenitor cells, whereas coculture with γ-secretase inhibitor or the presence of mutation in the presenilin1 gene blocked the effects of mood stabilizers. In addition, chronic administration of mood stabilizers expanded the NSC pool in the adult brain, which subsequently increased the cell supply to the olfactory bulb. We suggest that treatment with mood stabilizing drugs could be used to facilitate regeneration following insult to the central nervous system. Disclosure of potential conflicts of interest is found at the end of this article.

Fas ligand (FasL) binds Fas (CD95) to induce apoptosis or activate other signaling pathways. In addition, FasL transduces bidirectional or ‘reverse signals’. The intracellular domain of FasL contains consensus sequences for phosphorylation and an extended proline rich region, which regulate its surface expression through undetermined mechanism(s). Here, we used a proteomics approach to identify novel FasL interacting proteins in Schwann cells to investigate signaling through and trafficking of this protein in the nervous system. We identified two novel FasL interacting proteins, sorting nexin 18 and adaptin β, as well as two proteins previously identified as FasL interacting proteins in T cells, PACSIN2 and PACSIN3. These proteins are all associated with endocytosis and trafficking, highlighting the tight regulation of cell surface expression of FasL in the nervous system.

A critical unresolved issue about the DNA damage/genotoxic stress response is how the resulting activation of the p53 tumor suppressor can lead either to cell cycle arrest and DNA repair, or to apoptosis. We show here that Hematopoietic Zinc Finger (Hzf), a zinc finger containing p53 target gene, modulates p53 transactivation functions in an autoregulatory feedback loop. Hzf is induced by p53 and binds to its DNA binding domain, resulting in preferential transactivation of pro-arrest p53 target genes over its pro-apoptotic target genes. Thus p53 activation results in cell cycle arrest in Hzf wt-MEFs while in Hzf−/− MEFs apoptosis is induced. Additionally, prolonged exposure to stress results in Hzf degradation concomitant with induction of apoptosis. Exposure of Hzf-null mice to IR resulted in enhanced apoptosis in several organs including skin and prostate, as compared to that of wt-mice. These findings provide novel insights into the regulation of p53 transactivation function that plays an important role in cell fate decisions in response to genotoxic stress.

Local protein synthesis in dendrites plays an important role in some aspects of neuronal development and synaptic plasticity. Neuronal RNA-binding proteins regulate the transport and/or translation of the localized mRNAs. Previously, we reported that hematopoietic zinc finger (Hzf) is one of the neuronal RNA-binding proteins that regulate these processes. The Hzf protein is highly expressed in neuronal cells including hippocampal pyramidal neurons and cerebellar Purkinje cells, and plays essential roles in the dendritic mRNA localization and translation. In the present study we demonstrated that mice lacking Hzf (Hzf(-/-) mice) exhibited severe impairments of motor coordination and cerebellum-dependent motor learning. These findings raise the possibility that the post-transcriptional regulation by Hzf may contribute to some aspects of synaptic plasticity and motor learning in the cerebellum.

Gamma-secretase catalyzes intramembraneous proteolysis of several type I transmembrane proteins, including beta-amyloid precursor protein (APP), to generate amyloid beta protein (Abeta), a key player in the pathogenesis of Alzheimer's disease (AD). The critical components of the gamma-secretase complex include presenilin (PS), nicastrin (NCT), presenilin enhancer-2 (PEN-2) and anterior pharynx defective-1 (APH-1). Abnormalities of the ubiquitin-proteasome pathway have been implicated in the pathogenesis of AD; while PS and PEN-2 turnover is regulated by this pathway, it is unknown whether the ubiquitin-proteasome pathway is also involved in the degradation of APH-1 protein. In this study, we found that the expression of endogenous and exogenous APH-1 significantly increased in cells treated with proteasome-specific inhibitors. The effect of the proteasome inhibitors on APH-1 was dose- and time-dependent. APH-1 protein was ubiquitinated. Pulse-chase metabolic labeling experiments showed that the degradation of newly synthesized radiolabeled APH-1 proteins was inhibited by lactacystin. Disruption of the PS1 and PS2 genes did not affect the degradation of APH-1 by the ubiquitin-proteasome pathway. Furthermore, over-expression of APH-1 and inhibition of proteasomal APH-1 degradation facilitated gamma-secretase cleavage of APP to generate Abeta. These results demonstrate that the degradation of APH-1 protein is mediated by the ubiquitin-proteasome pathway.

The fact that several different human virus oncoproteins, including adenovirus type 9 E4-ORF1, evolved to target the Dlg1 mammalian homolog of the membrane-associated Drosophila discs-large tumor suppressor has implicated this cellular factor in human cancer. Despite a general belief that such interactions function solely to inactivate this suspected human tumor suppressor protein, we demonstrate here that E4-ORF1 specifically requires endogenous Dlg1 to provoke oncogenic activation of phosphatidylinositol 3-kinase (PI3K) in cells. Based on our results, we propose a model wherein E4-ORF1 binding to Dlg1 triggers the resulting complex to translocate to the plasma membrane and, at this site, to promote Ras-mediated PI3K activation. These findings establish the first known function for Dlg1 in virus-mediated cellular transformation and also surprisingly expose a previously unrecognized oncogenic activity encoded by this suspected cellular tumor suppressor gene.

Recently, Notch signaling has been reported to underscore the ability of neural stem cells (NSCs) to self-renew. Utilizing mice deficient in presenilin-1(PS1), we asked whether the function of Notch signaling in NSC maintenance was conserved. At embryonic day 14.5, all NSCs – both similar (cortex-, ganglionic eminence- and hindbrain-derived) and distinct (retinal stem cell) – require Notch signaling in a gene-dosage-sensitive manner to undergo expansionary symmetric divisions, as assessed by the clonal, in vitro neurosphere assay. Within the adult, however, Notch signaling modulates cell cycle time in order to ensure brain-derived NSCs retain their self-renewal property. At face value, the effects in the embryo and adult appear different. We propose potential hypotheses, including the ability of cell cycle to modify the mode of division, in order to resolve this discrepancy. Regardless, these findings demonstrate that PS1, and presumably Notch signaling, is required to maintain all NSCs.

The localization of certain mRNAs to dendrites and their local translation in synaptic regions are proposed to be involved in certain aspects of synaptic plasticity. A cis -acting element within the 3′ untranslated region (3′ UTR) of the targeted mRNAs, which is bound by a trans-acting RNA-binding protein, controls the dendritic mRNA localization. Here, we identified hematopoietic zinc finger (Hzf) as a trans-acting factor that regulates the dendritic mRNA localization of the type 1 inositol 1,4,5-trisphosphate receptor (IP 3 RI), a dendritically localized mRNA in cerebellar Purkinje cells, via binding to the 3′ UTR. In Hzf -deficient mice, the dendritic localization of IP 3 RI mRNA and brain-derived neurotrophic factor-induced IP 3 RI protein synthesis in the cerebellum were impaired. These findings suggest that Hzf is an RNA-binding protein that controls the dendritic mRNA localization and activity-dependent translation of IP 3 RI, and may be involved in some aspects of synaptic plasticity.

Mutagenesis of the epithelial polarity gene, discs large 1 , perturbs nephrogenesis in the developing mouse kidney. Background During development of the permanent mammalian kidney (metanephros) several key epithelial events occur such as ureteric branching morphogenesis and nephrogenesis. One of the first stages of nephrogenesis involves the conversion of mesenchymal cells to epithelial cells, and thus the metanephros provides an excellent model to study epithelial polarization. The aim of this study was to investigate the role of the epithelial polarity gene, discs large 1 ( dlg1 ), during development of the mouse kidney. Methods We utilized mice with a gene trap vector insertion within dlg1 ( dlg gt ) resulting in a truncated Dlg1 protein, lacking the SH3, protein 4.1 and guanylate kinase-like (GUK) domains, fused to a LacZ reporter. These mice were used to analyze the expression of Dlg1 during kidney development, the subcellular localization of Dlg1 in epithelial cells, and the ability of Dlg1 to bind to calmodulin-associated serine/threonine kinase (CASK). Metanephric organ culture was used to study branching morphogenesis and nephrogenesis in wild-type and dlg gt mutant mice. Results Dlg1 was expressed in ureteric and mesenchyme-derived epithelial cells during kidney development. Truncation of Dlg1 altered the normal basolateral localization of Dlg1 restricting it to the adherens junction. Due to the loss of the SH3 domain the binding capacity of Dlg1 to CASK was reduced. Nephrogenesis was altered in dlg gt /dlg gt metanephroi with a 30% decrease in nephron number. Conclusion Our results indicate that the loss of the SH3, protein 4.1 and/or GUK domains of Dlg1 disrupt epithelial polarity and perturb nephrogenesis either as a secondary consequence to a defect in ureteric branching morphogenesis and/or delay in mesenchyme-to- epithelial transition.

The development of the cardiovascular system and the development of the early hematopoietic systems are closely related, and both require signaling through the Tie2 receptor tyrosine kinase. Although endothelial cells and hematopoietic cells as well as their precursors share common gene expression patterns during development, it remains completely unknown how Tie2 signaling coordinately regulates cardiovascular development and early hematopoiesis in vivo. We show here that mice with a targeted mutation in tyrosine residue 1100 in the carboxyl-terminal tail of Tie2 display defective cardiac development and impaired hematopoietic and endothelial cell development in the paraaortic splanchnopleural mesoderm similar to that seen in Tie2-null mutant mice. Surprisingly, however, unlike Tie2-null mutant mice, mice deficient in signaling through this tyrosine residue show a normal association of perivascular cells with nascent blood vessels. These studies are the first to demonstrate the physiological importance of a single tyrosine residue in Tie2, and they suggest that multiple tyrosine residues in the receptor may coordinate cardiovascular development and early hematopoietic development.

German Idealism and the Jew: The Inner Anti-Semitism of Philosophy and German Jewish Responses, by Michael Mack. Chicago: University of Chicago Press, 2003. 229 pp. $35.00 (c). The Rhetoric of Cultural Dialogue: Jews and Germans from Moses Mendelssohn to Richard Wagner and Beyond, by Jeffrey S. Librett. Stanford: Stanford University Press, 2000. 426 pp. $75.00 (c); $29.95 (p). Spinoza's Modernity: Mendelssohn, Lessing, and Heine, by Willi Goetschel. Madison: University of Wisconsin Press, 2004. 368 pp. $45.00 (c); $29.95 (p). Jeffrey Librett begins The Rhetoric of Cultural Dialogue: Jews and Germans from Moses Mendelssohn to Richard Wagner and Beyond with a sobering passage from Gershom Scholem's 1962 essay "Against the Myth of the German-Jewish Dialogue." Given that this passage can serve as the conceptual starting point for Michael Mack's and Willi Goetschel's studies as well, I will quote it at some length: "I deny that there has ever been...a German-Jewish dialogue in any genuine sense whatsoever, i.e., as a historical phenomenon. It takes two to have a dialogue, who listen to each other, who are prepared to perceive the other as what he is and represents, and to respond to him. Nothing can be more misleading than to apply such a concept to the discussions between Germans and Jews during the last 200 years. The dialogue died at its very start and never took place.... To be sure, the Jews attempted a dialogue with the Germans, starting from all possible points of view and situations.... The attempt of the Jews to explain themselves to the Germans and to put their own creativity at their disposal, even to the point of complete self-abandonment (Selbstaufgabe), is a significant phenomenon.... In this, I am unable to perceive anything of a dialogue" (p. xv). If the history of German Jewry is marked by continually having to respond to (and account for) accusations made by an unwilling partner, then we might suggest (with Scholem) that the dialogue between Jews and Germans was, from the beginning, a marked discourse. This suggestion is borne out by the provocative thesis of Mack's German Idealism and the Jew: The Inner Anti-Semitism of Philosophy and German Jewish Responses, which holds that there are certain antisemitic tropes occurring in 19th-century German philosophical and cultural writings which provide a justification for German antisemitic practices over a century later (p. 3). Rather than being merely incidental aspects of German philosophy, Mack holds that these tropes are a manifestation of "the presence of irrationality in the self-declared `rational' philosophies of Kant [and] Hegel" (p. 1). Both Mack and Librett are fairly explicit about the normative and binary structure of these tropes; German antisemitic discourse revolves around three oppositions: spirit/letter, spirit/matter, and autonomy/heteronomy. In each case (and in all cases), non-Jewish Germans (or perhaps, in Scholem's view, just "Germans") occupy the former term of this opposition. Consequently, in the language of these tropes, Jews are continually perceived as (and thus denigrated to) the "literal embodiment" of the latter term. For this reason, as Goetschel suggests in Spinoza's Modernity: Mendelssohn, Lessing, and Heine, any and all visible traces of "Jewishness" strikes German philosophy (with its universalizing tendencies) as a scandal (p. 5). It would be fairly easy to view this historical illustration of Jewish-German (non)relations in a despairing manner. In one sense, this is precisely what Scholem's passage does. This is understandable, given Scholem's radical proximity to the Shoah and the morbid awakening into which it forced worldwide Jewry. For this reason, Scholem is not concerned with reclaiming the intellectual history of German-Jewish relations for a new age. After Auschwitz, he quite rightly views Jewish contributions to German culture (e.g., the Buber-Rosenzweig translation of the Hebrew Bible) as having amounted to "the tombstone of a relationship that was extinguished in unspeakable horror. …

The roles of PDZ domain-containing proteins such as Dlg and Scrib have been well described for Drosophila; however, their requirement for mammalian development is poorly understood. Here we show that Dlg, Scrib, MAGI1, MAGI3, and MPDZ are expressed in the mouse ocular lens. We demonstrate that the increase in proliferation and defects in cellular adhesion and differentiation observed in epithelia of lenses that express E6, a viral oncoprotein that can bind to several PDZ proteins, including the human homologs of Dlg and Scrib, is dependent on E6's ability to bind these proteins via their PDZ domains. Analyses of lenses from mice carrying an insertional mutation in Dlg (dlg(gt)) show increased proliferation and proliferation in spatially inappropriate regions of the lens, a phenotype similar to that of lenses expressing E6. The results from this study indicate that multiple PDZ domain-containing proteins, including Dlg and Scrib, may be required for maintaining the normal pattern of growth and differentiation in the lens. Furthermore, the phenotypic similarities among the Drosophila dlg mutant, the lenses of dlg(gt) mice, and the lenses of E6 transgenic mice suggest that Dlg may have a conserved function in regulating epithelial cell growth and differentiation across species.

The molecular mechanisms responsible for organ-specific differences in vascular development are not well established. Animals lacking the receptor tyrosine kinase Tie1 die of hemorrhage and pulmonary edema. Furthermore, cells lacking Tie1 are excluded from blood vessels of the mature lung. These findings suggest the importance of Tie1 in the pulmonary vasculature. We quantified the organ-specific expression of Tie1 during embryonic and postnatal murine development using both quantitative real-time polymerase chain reaction (PCR) and chemiluminescence employing a tie1.lacZ reporter. In the lung, Tie1 expression increases markedly immediately prior to birth and rises further in the newborn animal, a pattern not found in other organs. Furthermore, expression of Tie1 in the lung is also unique by its persistent increase in the adult animal. This unique pattern of Tie1 gene expression in the embryonic and mature lung supports a distinct role for Tie1 in the development and function of the pulmonary vasculature.

Postsynaptic targeting of the Drosophila tumour suppressor discs-large (Dlg) critically depends on its SH3 and GK domains. Here, we asked whether these domains are also involved in subcellular targeting of the mammalian Dlg homolog SAP97 and its interacting partners in CNS cortical neurons by analysing a recently described mouse mutant lacking the SH3 and GK domains of SAP97. Both wildtype and truncated SAP97 were predominantly expressed in perinuclear regions, in a pattern suggesting association with the endoplasmic reticulum. Weaker immunoreactivity was found in neurites colocalizing with both dendritic and axonal markers. As SAP97 has been implicated in the early intracellular processing of the glutamate receptor GluR1, we studied biochemical maturation and subcellular localization of GluR1 in the mutants. Both the glycosylation pattern and synaptic clustering of GluR1 were indistinguishable from wildtype mice. Synaptic clustering of the guanylate kinase domain interacting protein GKAP was also intact. Our data demonstrate that truncation of the SH3 and GK domains of SAP97 in mice does neither change its subcellular distribution nor does it disrupt synaptic structure or protein clustering, as opposed to severe missorting of the respective mutant Dlg protein in Drosophila.

Neural stem cells, which exhibit self-renewal and multipotentiality, are generated in early embryonic brains and maintained throughout the lifespan. The mechanisms of their generation and maintenance are largely unknown. Here, we show that neural stem cells are generated independent of RBP-Jκ, a key molecule in Notch signaling, by using RBP-Jκ−/− embryonic stem cells in an embryonic stem cell-derived neurosphere assay. However, Notch pathway molecules are essential for the maintenance of neural stem cells; they are depleted in the early embryonic brains ofRBP-Jκ−/− or Notch1−/− mice. Neural stem cells also are depleted in embryonic brains deficient for the presenilin1 (PS1) gene, a key regulator in Notch signaling, and are reduced in PS1+/− adult brains. Both neuronal and glial differentiation in vitro were enhanced by attenuation of Notch signaling and suppressed by expressing an active form of Notch1. These data are consistent with a role for Notch signaling in the maintenance of the neural stem cell, and inconsistent with a role in a neuronal/glial fate switch.

Using an expression gene trapping strategy, we recently identified a novel gene, hematopoietic zinc finger (Hzf), which encodes a protein containing three C2H2-type zinc fingers that is predominantly expressed in megakaryocytes. Here, we have examined the in vivo function of Hzf by gene targeting and demonstrated that Hzf is essential for megakaryopoiesis and hemostasis in vivo. Hzf-deficient mice exhibited a pronounced tendency to rebleed and had reduced α-granule substances in both megakaryocytes and platelets. These mice also had large, faintly stained platelets, whereas the numbers of both megakaryocytes and platelets were normal. These results indicate that Hzf plays important roles in regulating the synthesis of α-granule substances and/or their packing into α-granules during the process of megakaryopoiesis.

Notch receptors undergo three distinct proteolytic cleavages during maturation and activation. The third cleavage occurs within the plasma membrane and results in the release and translocation of the intracellular domain into the nucleus to execute Notch signaling. This so-called γ-secretase cleavage is under the control of presenilins, but it is not known whether presenilins themselves carry out the cleavage or whether they act by means of yet-unidentified γ-secretase(s). In this article, we show that Notch intracellular cleavage in intact cells completely depends on presenilins. In contrast, partial purification of the Notch cleavage activity reveals an activity, which is present only in protein extracts from presenilin-containing cells, and which does not comigrate with presenilin. This finding provides evidence for the existence of a specific Notch-processing activity, which is physically distinct from presenilins. We conclude from these experiments that presenilins are critically required for Notch intracellular cleavage but are not themselves directly mediating the cleavage.

We are in the midst ofa profound revolution in health research, a revolution being driven by our emerging understanding of the molecular basis of life and human disease. This revolution is creating a century of health research, characterized by the convergence of virtually all disciplines, from mathematics to the social sciences and humanities. This convergence of disciplines is introducing radical changes and opportunities in the discovery and R&D process of health research. Academic health sciences centres (AHSCs) are strategically placed to contribute to, and benefit from, this revolution. To that end AHSCs require exceptional visionary leadership, a commitment to clinical and research excellence, a full appreciation of the complete tripartite mission of AHSCs, and the development of an outward-looking stance that includes the development of public policy. The federal governments clear and sustained commitment to health research, as demonstrated recently by the 15% increase to the Canadian Institutes of Health Research budget, provides an important opportunity for AHSCs to demonstrate their crucial role in both the development of an innovative and cost-effective healthcare system and to Canada's broader social and economic agenda.

In 1985, an Institute of Medicine report (Division of Health Promotion and Disease Prevention and Institute of Medicine, 1985) stated: “Vaccines are an elegant solution to one of the perennial problems of the human race—infectious disease. The body's own protective mechanisms are primed by specific interventions to thwart the invasion of or multiplication of pathogenesis.” Vaccines are indeed one of the great triumphs of modern medicine and public health: they prevent disease, they are relatively inexpensive, easy to deliver and their effects long lasting, and their mechanism of action relies entirely on activation of our body's own protective immunological mechanisms. Yet, despite the historic successes of vaccines, or perhaps because of these successes, vaccinology has evolved to rely almost entirely on an empirical, trial-and-error process, in which the pathways to protective immunity—the early events that lead to the development of long-lived protection against infection by a given pathogen—remain largely unknown, and for those successful vaccines, largely unnecessary to know (D'Argenio and Wilson, 2010). Despite this, vaccinology is undoubtedly the most powerful public health intervention available, saving millions of lives and preventing disease in hundreds of millions of people worldwide. However, a better understanding of the immune response, coupled with an improved ability to elicit these responses by immunization, appears to be key to future success in vaccine development against pathogens such as HIV, tuberculosis (TB), and malaria, that have, to date, been resistant to traditional trial-and-error approaches. These three pathogens—the big three—account for a significant proportion of premature deaths and morbidity worldwide. In addition, the burden of treating these diseases has siphoned significant financial and health care resources away from other urgent global health needs. Over 11 million people live with TB, almost 250 million cases of malaria, including approximately 1 million deaths in children, were reported in 2008, whereas over 33 million people worldwide are living with HIV/AIDS, including 2.5 million people who became newly infected with HIV in 2009. Recent advances in our understanding of the human immune system and the intertwined functions of the innate and adaptive immune response, as well as new insights into host–pathogen interactions, and the development of powerful new postgenomic technologies, are now available to be focused on developing, testing, and improving vaccine candidates. One indirect and largely unanticipated side effect of the Human Genome Project has been a transformation in the power of modern biology, driven by the development of powerful new “omic” technologies (genomics, proteomics, etc.), and associated computational and high-throughput technologies. Together, these advances are fueling the development of a new science of systems biology that has opened up the ability to understand the overall architecture of complex biological systems. These advances have led to the development of new clinical investigative tools, which has made the human a robust experimental organism for discovery research (Brenner, 2003). It is timely, therefore, to undertake the development of a new science of vaccinomics that is grounded in leading edge science, including systems biology, and a culture of science-driven clinical trials and clinical research. The goals of this new science of vaccinomics or systems vaccinology (Pulendran et al., 2010) are to develop new vaccines through understanding the global architecture of the human immune response and the changes that occur following vaccination, and to define the correlates of protection, or more appropriately, the signatures of protection that are required to elicit a protective immune response. Vaccine development has largely been focused on trying to identify a specific immune response that might be exploited to develop a vaccine capable of eliciting long-lived protection against a pathogen (Plotkin, 2008). However, the power of a systems approach in unraveling potentially novel mechanisms of vaccine action, and in enabling the prediction of the immunogenicity and efficacy of vaccines, has been highlighted by recent studies (Gaucher et al., 2008; Querec et al., 2009; Young et al., 2008). With the development of high-throughput approaches that allow exploration of the interconnected networks that control and drive the immune response, vaccine development is on the verge of a fundamental shift from the search for a single correlate (or multiple, independent correlates), to the identification of multifactorial signatures associated with immunological protection. This new science of vaccinomics also promises to close the current gap between clinical trials and discovery science, a gap that has compromised vaccine development. As highlighted in the 2010 Scientific Strategic Plan of the Global HIV Vaccine Enterprise (The Council of the Global HIV Vaccine Enterprise, 2010), human clinical trials no longer need be considered as separate from fundamental research but rather can be viewed and conducted as an integral part of the research continuum between discovery and clinical testing. This transformation in thinking has been made possible by the development of robust systems biology approaches to aid both in the design and testing of novel vaccine concepts and the analysis of the complexity of the immune response in humans. With powerful new laboratory and computational techniques, the design and testing of novel vaccine candidates in humans has become feasible. Capturing the full advantage of these advances, however, will require real-time laboratory analysis in order to extract the full depth of immunological, epidemiological, and clinical information that a well-conceived and conducted trial can yield. This objective will only be realized through close partnership between basic and translational scientists, computational biologists, clinicians, statisticians, industry, regulatory authorities, and funders.

Presenilin 1 (PS1), a polytopic membrane protein, has a critical role in the trafficking and proteolysis of a selected set of transmembrane proteins. The vast majority of individuals affected with early onset familial Alzheimer's disease (FAD) carry missense mutations in PS1. Two studies have suggested that loss of PS1 function, or expression of FAD-linked PS1 variants, compromises the mammalian unfolded-protein response (UPR), and we sought to evaluate the potential role of PS1 in the mammalian UPR. Here we show that that neither the endoplasmic reticulum (ER) stress-induced accumulation of BiP and CHOP messenger RNA, nor the activation of ER stress kinases IRE1alpha and PERK, is compromised in cells lacking both PS1 and PS2 or in cells expressing FAD-linked PS1 variants. We also show that the levels of BiP are not significantly different in the brains of individuals with sporadic Alzheimer's disease or PS1-mediated FAD to levels in control brains. Our findings provide evidence that neither loss of PS1 and PS2 function, nor expression of PS1 variants, has a discernable impact on ER stress-mediated induction of the several established 'readouts' of the UPR pathway.

The ETS gene Fli-1 is involved in the induction of erythroleukemia in mice by Friend murine leukemia virus and Ewings sarcoma in children. Mice with a targeted null mutation in the Fli-1 locus die at day 11.5 of embryogenesis with loss of vascular integrity leading to bleeding within the vascular plexus of the cerebral meninges and specific downregulation of Tek/Tie-2, the receptor for angiopoietin-1. We also show that dysmegakaryopoiesis in Fli-1 null embryos resembles that frequently seen in patients with terminal deletions of 11q (Jacobsen or Paris-Trousseau Syndrome). We map the megakaryocytic defects in 14 Jacobsen patients to a minimal region on 11q that includes the Fli-1 gene and suggest that dysmegakaryopoiesis in these patients may be caused by hemizygous loss of Fli-1.

Mastocytosis is characterized by abnormal infiltration of mast cells into various organs. An activating mutation in c-kit, involving an A --> T substitution at nucleotide 2648 has recently been described in some patients with mastocytosis. We describe a 12-year-old girl with this mutation in her bone marrow cells at diagnosis with a myelodysplastic syndrome (MDS) without evidence of mastocytosis, and then in peripheral blood mononuclear cells 1 year later after the emergence of mastocytosis. The role of the c-Kit receptor and its ligand stem cell factor (SCF) in the pathogenesis of the disease was analysed in marrow cell clonogenic assays. We show that the genetic abnormalities in the patient resulted in factor-independent growth and hypersensitivity of primitive progenitors to SCF, with increased production of mast cells. Increased apoptosis and cluster formation, consistent with the myelodysplastic nature of the disorder, accompanied accumulation of abnormal cells with increasing concentrations of SCF.

TEK (TIE2) and TIE (TIE1) are structurally related receptor tyrosine kinases expressed in endothelial cells and their precursors. Genetic studies in the mouse have revealed essential functions of both receptors in angiogenic expansion of the vasculature during development. As previously shown, mouse embryos homozygous for a disrupted Tek allele die by day 10.5 of embryogenesis due to endocardial defects, hemorrhaging, and impaired vascular network formation. Furthermore, TIE is required cell autonomously for endothelial cell survival and extension of the vascular network during late embryogenesis. Here we have investigated possible redundancy in the TEK and TIE signalling pathways during vascular development. Vasculogenesis proceeds normally in embryos lacking both TEK and TIE, although such embryos die early in gestation of multiple cardiovascular defects. Mosaic analysis revealed an absolute requirement for TEK in the endocardium at E10.5, whereas TEK and TIE are dispensable for the initial assembly of the rest of the vasculature. In contrast, both receptors are required in the microvasculature during late organogenesis and in essentially all blood vessels of the adult. This analysis demonstrates essential functions for TEK and TIE in maintaining the integrity of the mature vasculature.

We have developed a large-scale, expression-based gene trap strategy to perform genome-wide functional analysis of the murine hematopoietic and vascular systems. Using two different gene trap vectors, we have isolated embryonic stem (ES) cell clones containing lacZreporter gene insertions in genes expressed in blood island and vascular cells, muscle, stromal cells, and unknown cell types. Of 79 clones demonstrating specific expression patterns, 49% and 16% were preferentially expressed in blood islands and/or the vasculature, respectively. The majority of ES clones that expressedlacZ in blood islands also expressed lacZ upon differentiation into hematopoietic cells on OP9 stromal layers. Importantly, the in vivo expression of the lacZ fusion products accurately recapitulated the observed in vitro expression patterns. Expression and sequence analysis of representative clones suggest that this approach will be useful for identifying and mutating novel genes expressed in the developing hematopoietic and vascular systems.

In a retinoic acid (RA) gene- trap screen of mouse embryonic stem (ES) cells, a novel gene, named Aquarius (Aqr), was identified and characterized. The promoterless lacZ marker was used to trap the genomic locus and to deter- mine the expression pattern of the gene. Aqr transcripts are strongly induced in response to RA in vitro. During embryogenesis, Aqr is ex- pressed in mesoderm, in the neural crest and its target tissues, and in neuroepithelium. Expres- sion was first detected at 8.5 days postcoitum, when neural crest cells are visible at the lateral ridges of the neural plate. The gene-trapped Aqr locus was transmitted through the mouse germ line in three genetic backgrounds. In the F2 generation, the expected mendelian ratio of 1:2:1 was observed in all backgrounds, indicating that homozygous mice are viable. Homozygotes are normal in size and weight and breed normally. The gene trap insertion, however, does not seem to generate a null mutation, because Aqr tran- scripts are still present in the homozygous mu- tant animals. The Aqr open reading frame has weak homology to RNA-dependent RNA polymer- ases (RRPs) of the murine hepatitis viruses and contains an RRP motif. Aqr was mapped to mouse chromosome 2 between regions E5 through F2 by using fluorescence in situ hybridization analysis. Dev. Dyn. 1998;212:304-317. r 1998 Wiley-Liss, Inc.

NIMA protein kinase is a major regulator of progression into mitosis in Aspergillus nidulans. Dominant negative forms of NIMA protein prevent entrance into mitosis in HeLa cells, suggesting that mammals have a similar pathway. We have reported previously the isolation of a murine NIMA-related kinase, designated Nek1, and more recently several additional NIMA-related human kinases have been cloned. The existence of several mammalian NIMA-related genes raises the questions of whether the different mammalian members have redundant, overlapping or distinct functions, and whether these functions are related to the role of NIMA in controlling mitosis. To address these questions we have studied the expression patterns of the different murine nek genes. To this end, we isolated a murine nek2 cDNA and compared its patterns of expression, during both gametogenesis and embryogenesis, to those of nek1. Both genes were highly expressed in developing germ cells, albeit in distinct patterns. In both females and males, nek1 is expressed much earlier than nek2, suggesting only limited ability for functional redundancy. Surprisingly, a striking specificity of nek1 expression was found: high levels of nek1 RNA were observed in distinct regions of the nervous system, most notably in neurons of the peripheral ganglia. These patterns suggest that the different mammalian NIMA-related kinases participate in different phases of the meiotic process and may also have functions other than cell cycle control.

Interstitial cells of Cajal (ICCs) form a network of cells between the external longitudinal and circular muscle layers at the level of the Auerbach's plexus in the mammalian small intestine. These cells express the Kit receptor tyrosine kinase and are essential for intestinal pacemaker activity. W mutant mice carrying structural mutations in the Kit gene lack both the network of ICCs and intestinal pacemaker activity. We were interested in the developmental origin of the cells that make up the network of ICCs. In addition, the specific stages of ICC development that require a functional Kit receptor have not been characterized. We show that ICCs originate from mesenchymal progenitor cells that coexpress both Kit and smooth muscle myosin heavy chain, a marker specific for smooth muscle, during embryogenesis. ICC and longitudinal smooth muscle lineages begin to diverge late in gestation. Embryos homozygous for the regulatory Wbanded (Wbd) mutation do not express Kit in these mesenchymal progenitor cells. Nevertheless, Wbd/Wbd mice display a normal network of ICCs and normal smooth muscle layers at postnatal day 5 (p5). Adult Wbd/Wbd mice lack a functional ICC network and intestinal pacemaker activity due to a failure of the ICCs to increase in numbers after p5. These data suggest a common developmental origin of the ICCs and the longitudinal smooth muscle layers in the mammalian small intestine and show that Kit expression is necessary for the postnatal development and proliferation of ICCs but not for the initial cell lineage decision toward an ICC fate during embryogenesis or for smooth muscle development.

Since Valdosta State became a Regional University, Odum Library has experienced an explosion in student use in new technologies. This rapid rate of change prompted the library to try to gain a clear sense of whether we were meeting students' needs. Thus, when the ALA asked libraries to administer a “customer satisfaction” survey during National Library Week, Odum Library participated to gain insight into customers' attitudes and needs concerning the library, as well as to learn how our services compared with those of other academic libraries nationwide. Survey responses were actively solicited, and the objective and comment sections of the survey separately analyzed. The students' comment data emerged as much more valuable than the more easily analyzed objective questions. Coding and separating each section of a comment that dealt with a different topic revealed valuable, specific data which gave insight into each area of customer service. Social science literature describing the various merits o...

Immune and inflammatory responses must be rightly regulated to maintain a homoeostatic balance between an effective immune response and tissue damage to the host. NO is a principal mediator of many of the cytokine-inducible macrophage activities during a normal cell-mediated immune response. STK, the murine homologue of the human RON receptor tyrosine kinase, is expressed on murine resident peritoneal macrophages. The ligand for STK, macrophage-stimulating protein (MSP), is a serum protein that is activated by members of the coagulation cascade in response to tissue damage. In addition to its potential to induce chemotaxis and phagocytosis of C3bi-coated erythrocytes, MSP has an inhibitory effect on the production of NO by activated peritoneal macrophages in vitro. Here we demonstrate that peritoneal macrophages from mice lacking STK produce elevated levels of NO in response to interferon (IFN)-gamma in a dose-dependent manner, without the need for a co-stimulus. However, production of pro-inflammatory cytokines by activated macrophages from stk -/- mice is unaltered. In vivo, stk -/- mice exhibit increased inflammation in an IFN-gamma-mediated delayed-type hypersensitivity reaction and increased susceptibility to lipopolysaccharide (LPS)-induced endotoxic shock. Furthermore, the levels of NO in the serum of mice injected with LPS are significantly higher than those in control littermates. Nevertheless, the serum levels of IFN-gamma and the intermediate cytokines generated by the inflammatory response, which have previously been shown to play a role in septicaemic shock, do not differ significantly from controls. These data suggest that the STK receptor suppresses NO production, therefore ameliorating the potentially tissue-damaging effects of a cell-mediated immune response, through negative regulation of the IFN-gamma signalling pathway.

Mutations in the murine dominant white spotting (W) locus cause pleiotropic developmental defects that affect hematopoietic cells, melanocytes, germ cells and the interstitial cells of Cajal in the gut. W mutations either alter the coding sequence of the Kit receptor tyrosine kinase, resulting in a receptor with impaired kinase activity, or affect Kit expression. Here we describe the molecular and cell-type-specific developmental defects of two of the latter class of regulatory W alleles, W57 and Wbanded(bd). In both mutants, the temporal and spatial patterns of Kit expression are dysregulated during embryogenesis and in adult animals. In Wbd mice, ectopic expression of Kit in the dermatome of the somites at days 10.8 and 11.8 of development seemed to interfere with melanoblast development. In contrast, the W57 allele leads to an intrinsic pigmentation defect by downregulating developmental Kit expression in trunk melanoblasts, but not melanoblasts around the otic vesicle. Both mutations affect transcriptional initiation of the Kit gene. The W57 allele is associated with a 80 kb deletion 5′ of the Kit-coding region while Wbd is associated with a 2.8 Mb genomic inversion of chromosome 5 with the distal breakpoint between Kit and the platelet-derived growth factor receptor alpha (Pdgfra) gene, and the proximal breakpoint between the genes for the GABA receptor beta 1 (Gabrb1) and the Tec tyrosine kinase, juxtaposing the Kit and Tec tyrosine kinase genes. Neither W57 nor Wbd affect genomic sequences previously suggested in in vitro experiments to control cell-type-specific expression of Kit. These results link specific mechanisms of cellular and developmental defects to long-range genomic rearrangements that positively and negatively affect Kit transcription in different cell lineages as well as in different subpopulations of the same lineage.

Distinct and evolutionarily conserved signal transduction cascades mediate survival or death in response to developmental and environmental cues. The stress-activated protein kinases, or Jun N-terminal kinases (SAPKs/JNKs)1,2, are activated in response to a variety of cellular stresses such as changes in osmolarity and metabolism, DNA damage, heat shock, ischaemia, or inflammatory cytokines3–6. Sek1 (JNKK/MKK4) is a direct activator of SAPKs/JNKs in response to environmental stresses or mitogenic factors7–9. Here we investigate the role of Sek1 in development and apoptosis by deleting sek1 in embryonic stem (ES) cells by homologous recombination. We provide genetic evidence that different stresses utilize distinct signalling pathways for SAPK/ JNK activation, sek1−/− /rag2−/− chimaeric mice have normal numbers of mature T cells but fewer immature CD4+CD8+ thymocytes. The sek1 mutation did not affect the induction of apoptosis in response to environmental stresses in ES and T cells: instead, sek1 protected thymocytes from CD95 (Fas)- and CD3-mediated apoptosis. These data indicate that SEK1 mediates survival signals in T-cell development.

The W ( white-spotting ) locus encodes the Kit receptor tyrosine kinase. Mice with a loss-of-function mutation in the W/c-kit locus display defects in hemapoiesis, fertility, gut motility, spatial learning–memory, and nerve regeneration. Similar phenotypes are displayed in mice with mutations at the Steel ( Sl ) locus, which encodes the ligand for the Kit receptor, Steel factor (SLF). This article will review the phenotypes displayed by W mutant mice, the molecular basis of the mutations, the Kit–SLF signaling pathway, the isoforms of Kit, Kit mutations in human malignancies, and recent therapeutic strategies.