Function and evolution of the imprinted gene C15orf2 /NPAP1

Die chromosomale Region 15q11q13 enthält ein Cluster geprägter Gene, die entweder nur vom paternalen oder nur vom maternalen Chromosom exprimiert werden. Der Funktionsverlust paternal exprimierter Gene führt zum Prader-Willi-Syndrom. Obwohl der Funktionsverlust der SNORD116-Gene für die meisten Symptome des PWS verantwortlich zu sein scheint, könnten auch andere paternal exprimierte Gene eine Rolle spielen. Eines der geprägten Gene in der Region ist C15orf2, das im fetalen Gehirn ausschließlich vom paternalen Allel exprimiert wird und dessen monoallelische Expression im Rahmen dieser Arbeit auch im adulten Gehirn nachgewiesen wurde. Im Promotorbereich von C15orf2 befindet sich ein großes CpG-Island, von dem vermutet wurde, dass es an der Regulation der genomischen Prägung und Genexpression von C15orf2 beteiligt sei. Wie hier jedoch gezeigt wurde, ist das CpG-Island im Gehirn überwiegend methyliert und spielt für die Regulation der Expression vermutlich keine große Rolle. C15orf2 codiert für ein 1156 AS großes Protein mit sechs Kernlokalisationssignalen. Eine Protein-BLAST-Analyse sowie eine Analyse mit dem Signaturerkennungsprogramm InterProScan wiesen auf Sequenzhomologie mit dem Membrannukleoporin POM121 hin. Um herauszufinden, ob das C15orf2-Protein an den Kernporen lokalisiert ist, wurde eine stabile Zelllinie generiert, die FLAG-markiertes C15orf2 induzierbar exprimiert. In Immunfluoreszenzstudien an dieser Zelllinie wurde C15orf2 in der Zellkernperipherie detektiert, wo es mit NPCs und der Kernlamina co-lokalisiert war. Sehr hohe ektopische Expression führte in einigen Zellen zu einem Phänotyp mit Invaginationen der Zellkernhülle, die auf eine Störung der Kernhüllenintegrität bei unphysiologisch hohen C15orf2-Konzentrationen hinwiesen. Mit drei-dimensionaler strukturierter Illuminationsmikroskopie wurde die Kernhülle lichtmikroskopisch noch besser aufgelöst und eine spezifische Lokalisation von C15orf2 auf der nukleären Seite der NPCs beobachtet. Die NPC-Assoziation wurde zusätzlich mit einer Kernhüllen-Fraktionierungs-Methode biochemisch bestätigt. Im Rahmen dieser Arbeit wurde zum ersten Mal gezeigt, dass C15orf2 Teil des NPCs oder der NPC-assoziierten molekularen Netzwerke ist. Auf diesen Erkenntnissen basierend wurde vom „HUGO Gene Nomenclature Commitee“ der neue Name „Nuclear pore associated protein 1“ (NPAP1) für C15orf2 festgelegt. Das C15orf2-Gen besitzt kein murines Ortholog, war aber während der Primatenevolution einer starken positiven Selektion unterlegen und könnte daher wichtige primatenspezifische Funktionen besitzen. Im evolutionsbiologischen Teil dieser Arbeit wurde gezeigt, dassC15orf2 erst während der Primatenevolution in die chromosomale Region 15q11q13 integriert ist. In anderen Säugetieren, aber nicht in Nagetieren, wurden dagegen C15orf2-homologe Sequenzen gefunden, die hier NPAP1L genannt werden. Die NPAP1L-Gene in Säugetieren teilen Syntänie mit zwei humanen Pseudogenen auf Chromosom 9. Eine phylogenetische Analyse offenbarte die Existenz einer Genfamilie, die von dem vertebratenspezifischen Membrannukleoporin-Gen POM121 abstammt. Anders als POM121 sind die anderen Mitglieder der Familie, NPAP1L, NPAP1 und UPF0607, intronlos oder besitzen kleine, sekundär gebildete Introns. Daher ist ihr gemeinsamer Vorfahre vermutlich durch Retrotransposition von POM121 während einer frühen Phase der Säugetierevolution entstanden. NPAP1L unterlief in einigen Säugetierlinien segmentalen Duplikationen und ist in Nagetieren sekundär verloren gegangen. In der Primatenlinie führten vermutlich zwei weitere Retrotranspositionsereignisse zu den Schwestergenen C15orf2 und UPF0607, während NPAP1L hier zu einem Pseudogen wurde. Diese Ergebnisse zeigen, dass C15orf2 von dem Nukleoporin-Gen POM121 abstammt und zu einer Familie von säuger- und primatenspezifischen Retrogenen gehört.The chromosomal region 15q11q13 contains a cluster of imprinted genes expressed from the paternal or maternal chromosome only. The loss of function of paternally expressed genes leads to Prader-Willi syndrome. Although the loss of function of the SNORD116 snoRNA cluster seems to be responsible for most clinical signs, other paternally expressed genes may also contribute to Prader-Willi syndrome. One of the imprinted genes in the region is C15orf2, which is expressed from the paternal chromosome only in fetal brain. In the course of this study, the monoallelic expression of C15orf2 was also shown in adult brain. However, the associated promoter CpG island was found to be heavily methylated on both alleles in the brain and therefore is unlikely to mediate the monoallelic expression. C15orf2 encodes an 1156 amino acid protein with six nuclear localization signals. Bioinformatic analyses showed significant sequence similarity with the transmembrane nucleoporin POM121. To investigate whether the C15orf2 protein is localized at the nuclear pore complex (NPC), a cell line was generated that expresses FLAG-tagged C15orf2 upon induction with doxycycline. In this cell line, immunofluorescence studies revealed the localization of C15orf2 at the nuclear periphery, where it co-localized with NPCs and the nuclear lamina. To further refine the subnuclear localization of C15orf2, super resolution microscopy with the 3D-SIM technology was applied. This technique revealed that the protein specifically localizes at the nucleoplasmic side of nuclear pore complexes, roughly in one layer with the nuclear lamina. The NPC association of C15orf2 was confirmed biochemically by a nuclear envelope fractionation approach. In the course of this study it was shown for the first time that C15orf2 is part of the NPC or its associated molecular networks. Based on these results, C15orf2 was renamed to ”Nuclear pore-associated protein 1” (NPAP1). The C15orf2 gene does not have an orthologue in the mouse, but it appears to have undergone strong positive selection in the primate lineage. In the evolutionary part of this work, it was shown that C15orf2 integrated into the chromosomal region 15q11q13 during primate evolution. In other mammals, but not in rodents, C15orf2-homologous sequences were identified, which were named NPAP1L. This group of orthologous genes share synteny with two human pseudogenes on chromosome 9. A phylogenetic analysis revealed the existence of a gene family with the three members NPAP1L, C15orf2, and UPF0607 that originated from the vertebrate-specific nucleoporin gene POM121, most likely by retrotransposition. These results for the first time show the relationship of C15orf2 and POM121 and introduce a new family of primate- and mammal-specific POM121-related retrogenes

Posttraumatic Stress Disorder Symptoms Contribute to Staff Perceived Irritability, Anger, and Aggression After TBI in a Longitudinal Veteran Cohort: A VA TBI Model Systems Study

Objective To examine the relationship between staff perceived irritability, anger, and aggression and posttraumatic stress disorder (PTSD) in veterans with traumatic brain injury (TBI) of all severity levels. Design Longitudinal cohort design. Setting Veterans Affairs Polytrauma Transitional Rehabilitation Programs. Participants Veterans and service members with TBI of all severity levels enrolled in the Veterans Affairs Polytrauma Rehabilitation Centers’ Traumatic Brain Injury Model System national database (N=240). Interventions Not applicable. Main Outcome Measure Univariable and multivariable logistic regression modeling was used to examine the association between irritability, anger, and aggression and potential risk factors, including PTSD symptoms. Irritability, anger, and aggression was measured as a single construct using an item from the Mayo-Portland Adaptability Inventory-4 that was rated by program staff at admission and discharge from the inpatient rehabilitation program. PTSD symptoms were assessed using the PTSD Checklist–Civilian Version. Results PTSD symptoms uniquely predicted program staff-rated irritability, anger, and aggression at discharge even after controlling for severity of TBI, age, male sex, education, and annual earnings. The model explained 19% of the variance in irritability, anger, and aggression. Conclusions When TBI severity and PTSD symptoms were considered simultaneously in a sample of veterans, only PTSD symptoms predicted staff-rated irritability, anger, and aggression. Given the negative outcomes linked with irritability, anger, and aggression, veterans may benefit from assessment and treatment of PTSD symptoms within rehabilitation settings

Dry Eye Diseases and Ocular Surgery: Practical Guidelines for Canadian Eye Care Practitioners

In 2014, the Canadian Dry Eye Disease Consensus Panel published Guidelines for screening, diagnosis and management of dry eye diseases (DED). These did not address the implications of DED for individuals who are being considered for or have recently undergone ocular surgery. DED is common in certain surgical cohorts, and the perisurgical setting poses specific challenges, both because surgery can complicate preexisting DED and because symptomatic and non-symptomatic DED place the patient at risk of poor surgical outcomes. The Consensus Panel has developed this Addendum to the 2014 Guidelines to offer guidance on DED care before and after ocular surgery

Asymmetric synthesis of propargylamines as amino acid surrogates in peptidomimetics

Wünsch M, Schröder DC, Fröhr T, et al. Asymmetric synthesis of propargylamines as amino acid surrogates in peptidomimetics. Beilstein Journal of Organic Chemistry. 2017;13:2428-2441.The amide moiety of peptides can be replaced for example by a triazole moiety, which is considered to be bioisosteric. Therefore, the carbonyl moiety of an amino acid has to be replaced by an alkyne in order to provide a precursor of such peptidomimetics. As most amino acids have a chiral center at C-alpha, such amide bond surrogates need a chiral moiety. Here the asymmetric synthesis of a set of 24 N-sulfinyl propargylamines is presented. The condensation of various aldehydes with Ellman's chiral sulfinamide provides chiral N-sulfinylimines, which were reacted with (trimethylsilyl) ethynyllithium to afford diastereomerically pure N-sulfinyl propargylamines. Diverse functional groups present in the propargylic position resemble the side chain present at the Ca of amino acids. Whereas propargylamines with (cyclo) alkyl substituents can be prepared in a direct manner, residues with polar functional groups require suitable protective groups. The presence of particular functional groups in the side chain in some cases leads to remarkable side reactions of the alkyne moiety. Thus, electron-withdrawing substituents in the C-alpha-position facilitate a base induced rearrangement to alpha, beta-unsaturated imines, while azide-substituted propargylamines form triazoles under surprisingly mild conditions. A panel of propargylamines bearing fluoro or chloro substituents, polar functional groups, or basic and acidic functional groups is accessible for the use as precursors of peptidomimetics

Folyóirat vagy gyűjteményes kötet? (Csokonai Diétai Magyar Múzsája)

BACKGROUND: The complex interplay between viral replication and host immune response during infection remains poorly understood. While many viruses are known to employ anti-immune strategies to facilitate their replication, highly pathogenic virus infections can also cause an excessive immune response that exacerbates, rather than reduces pathogenicity. To investigate this dichotomy in severe acute respiratory syndrome coronavirus (SARS-CoV), we developed a transcriptional network model of SARS-CoV infection in mice and used the model to prioritize candidate regulatory targets for further investigation. RESULTS: We validated our predictions in 18 different knockout (KO) mouse strains, showing that network topology provides significant predictive power to identify genes that are important for viral infection. We identified a novel player in the immune response to virus infection, Kepi, an inhibitory subunit of the protein phosphatase 1 (PP1) complex, which protects against SARS-CoV pathogenesis. We also found that receptors for the proinflammatory cytokine tumor necrosis factor alpha (TNFα) promote pathogenesis, presumably through excessive inflammation. CONCLUSIONS: The current study provides validation of network modeling approaches for identifying important players in virus infection pathogenesis, and a step forward in understanding the host response to an important infectious disease. The results presented here suggest the role of Kepi in the host response to SARS-CoV, as well as inflammatory activity driving pathogenesis through TNFα signaling in SARS-CoV infections. Though we have reported the utility of this approach in bacterial and cell culture studies previously, this is the first comprehensive study to confirm that network topology can be used to predict phenotypes in mice with experimental validation

ATRT-02. Neuropsychological function in infant atypical teratoid/rhabdoid tumor versus low-grade glioma survivors reflects tumor malignancy and multimodal treatment [Abstract]

BACKGROUND: Therapy of infants with brain tumors predisposes these patients to increased risks for cognitive sequelae, especially following radiotherapy. Neuropsychological outcome gains importance for those 40-60% of patients with an atypical teratoid/rhabdoid tumor (ATRT) who survive beyond 2 years. Still, reports on cognitive late-effects in children with ATRT are scarce compared to other pediatric brain tumor groups. We analyzed neuropsychological outcome for long-term ATRT-survivors registered in EU-RHAB and infant low-grade glioma (LGG) survivors from the SIOP-LGG 2004-study and LGG-registry. PATIENTS+METHODS: Age at diagnosis of both cohorts was 0-36 months. ATRT-patients (n=13) treated with up to 54Gy radiotherapy (median age 22 months (±7.1)) were evaluated with the “ATRT-Neuropsychology” tool based on SIOPE-BTG QoS-Group recommendations at median 6.8 years (±2.8) after diagnosis. LGG-patients (n=15) treated without radiotherapy (4/15 with chemotherapy) were analyzed with the German “Neuropsychological-Basic-Diagnostic” tool 5.2 years (±0.6) post-diagnosis. RESULTS: The ATRT- vs. LGG-cohorts were comparable for median age at diagnosis, sex-ratio and tumor-localization, though they differed slightly in median age at assessment (9.5/7.2 years (±2.5/1.1)). Results of age-appropriate tests showed increased impairments for ATRT-patients in fluid intelligence (FI) (p=.006, d=1.214) and in visual-spatial processing (VSP) (p<.001, d=2.233) compared to LGG-patients. The median for neuropsychological test results of ATRT-patients spanned from considerably below the normal to the lower normal range (median=65-90), while results of LGG-patients were mostly in the lower normal range (median=83-103). Results for psychomotor speed abilities (PMS) were distinctly below the norm for both patient groups (p=.002-.007). CONCLUSION: Infant ATRT- and LGG-patients develop significant impairments in PMS abilities following multimodal treatment. Long-term survivors of ATRT suffer from additional FI and VSP deficits. Our data suggest that high malignancy requiring multimodal treatment determines the inferior cognitive outcome for the ATRT-cohort. Long-term neuropsychological monitoring (and treatment options) should be implemented as standard of care in ATRT- and LGG-trials

Lignes directrices pratiques pour les professionnels canadiens des soins oculovisuels concernant la sécheresse oculaire et la chirurgie de l’œil

En 2014, le Groupe de consensus canadien sur la sécheresse oculaire a publié un document intitulé Dépistage, diagnostic et prise en charge de la sécher-esse oculaire : guide pratique à l’intention des optométristes canadiens. Ce guide pratique ne traitait pas des répercussions de la sécheresse oculaire chez les personnes en voie de subir une intervention chirurgicale de l’œil ou ayant récemment subi ce genre d’intervention. La sécheresse oculaire est courante dans certaines cohortes ayant subi une intervention chirurgicale, et le contexte périopératoire pose des problèmes précis; d’une part parce qu’une intervention chirurgicale peut compliquer une sécheresse oculaire préexistante et, d’autre part, parce la sécheresse oculaire symptomatique et asymptomatique expose le patient au risque d’obtenir des résultats chirur-gicaux médiocres. Le groupe de consensus a élaboré cet addenda au guide pratique de 2014 pour offrir des conseils sur les soins relatifs à la sécheresse oculaire avant et après une intervention chirurgicale aux yeux

Experimental evidence for temporal uncoupling of brain Aβ deposition and neurodegenerative sequelae

Brain A beta deposition is a key early event in the pathogenesis of Alzheimer ' s disease (AD), but the long presymptomatic phase and poor correlation between A beta deposition and clinical symptoms remain puzzling. To elucidate the dependency of downstream pathologies on A beta, we analyzed the trajectories of cerebral A beta accumulation, A beta seeding activity, and neurofilament light chain (NfL) in the CSF (a biomarker of neurodegeneration) in A beta-precursor protein transgenic mice. We find that A beta deposition increases linearly until it reaches an apparent plateau at a late age, while A beta seeding activity increases more rapidly and reaches a plateau earlier, coinciding with the onset of a robust increase of CSF NfL. Short-term inhibition of A beta generation in amyloid-laden mice reduced A beta deposition and associated glial changes, but failed to reduce A beta seeding activity, and CSF NfL continued to increase although at a slower pace. When short-term or long-term inhibition of A beta generation was started at pre-amyloid stages, CSF NfL did not increase despite some A beta deposition, microglial activation, and robust brain A beta seeding activity. A dissociation of A beta load and CSF NfL trajectories was also found in familial AD, consistent with the view that A beta aggregation is not kinetically coupled to neurotoxicity. Rather, neurodegeneration starts when A beta seeding activity is saturated and before A beta deposition reaches critical (half-maximal) levels, a phenomenon reminiscent of the two pathogenic phases in prion disease. The poor correlation between brain A beta deposition and clinical symptoms in Alzheimer ' s disease remains puzzling. Here, the authors show a temporal dissociation of A beta deposition and neurodegeneration

Orbital effects of a monochromatic plane gravitational wave with ultra-low frequency incident on a gravitationally bound two-body system

We analytically compute the long-term orbital variations of a test particle orbiting a central body acted upon by an incident monochromatic plane gravitational wave. We assume that the characteristic size of the perturbed two-body system is much smaller than the wavelength of the wave. Moreover, we also suppose that the wave's frequency is much smaller than the particle's orbital one. We make neither a priori assumptions about the direction of the wavevector nor on the orbital geometry of the planet. We find that, while the semi-major axis is left unaffected, the eccentricity, the inclination, the longitude of the ascending node, the longitude of pericenter and the mean anomaly undergo non-vanishing long-term changes. They are not secular trends because of the slow modulation introduced by the tidal matrix coefficients and by the orbital elements themselves. They could be useful to indepenedently constrain the ultra-low frequency waves which may have been indirectly detected in the BICEP2 experiment. Our calculation holds, in general, for any gravitationally bound two-body system whose characteristic frequency is much larger than the frequency of the external wave. It is also valid for a generic perturbation of tidal type with constant coefficients over timescales of the order of the orbital period of the perturbed particle.Comment: LaTex2e, 24 pages, no figures, no tables. Changes suggested by the referees include

Pathogenic Influenza Viruses and Coronaviruses Utilize Similar and Contrasting Approaches To Control Interferon-Stimulated Gene Responses

ABSTRACT The broad range and diversity of interferon-stimulated genes (ISGs) function to induce an antiviral state within the host, impeding viral pathogenesis. While successful respiratory viruses overcome individual ISG effectors, analysis of the global ISG response and subsequent viral antagonism has yet to be examined. Employing models of the human airway, transcriptomics and proteomics datasets were used to compare ISG response patterns following highly pathogenic H5N1 avian influenza (HPAI) A virus, 2009 pandemic H1N1, severe acute respiratory syndrome coronavirus (SARS-CoV), and Middle East respiratory syndrome CoV (MERS-CoV) infection. The results illustrated distinct approaches utilized by each virus to antagonize the global ISG response. In addition, the data revealed that highly virulent HPAI virus and MERS-CoV induce repressive histone modifications, which downregulate expression of ISG subsets. Notably, influenza A virus NS1 appears to play a central role in this histone-mediated downregulation in highly pathogenic influenza strains. Together, the work demonstrates the existence of unique and common viral strategies for controlling the global ISG response and provides a novel avenue for viral antagonism via altered histone modifications.IMPORTANCEThis work combines systems biology and experimental validation to identify and confirm strategies used by viruses to control the immune response. Using a novel screening approach, specific comparison between highly pathogenic influenza viruses and coronaviruses revealed similarities and differences in strategies to control the interferon and innate immune response. These findings were subsequently confirmed and explored, revealing both a common pathway of antagonism via type I interferon (IFN) delay as well as a novel avenue for control by altered histone modification. Together, the data highlight how comparative systems biology analysis can be combined with experimental validation to derive novel insights into viral pathogenesis