Proteomic Shifts in Embryonic Stem Cells with Gene Dose Modifications Suggest the Presence of Balancer Proteins in Protein Regulatory Networks

Large numbers of protein expression changes are usually observed in mouse models for neurodegenerative diseases, even when only a single gene was mutated in each case. To study the effect of gene dose alterations on the cellular proteome, we carried out a proteomic investigation on murine embryonic stem cells that either overexpressed individual genes or displayed aneuploidy over a genomic region encompassing 14 genes. The number of variant proteins detected per cell line ranged between 70 and 110, and did not correlate with the number of modified genes. In cell lines with single gene mutations, up and down-regulated proteins were always in balance in comparison to parental cell lines regarding number as well as concentration of differentially expressed proteins. In contrast, dose alteration of 14 genes resulted in an unequal number of up and down-regulated proteins, though the balance was kept at the level of protein concentration. We propose that the observed protein changes might partially be explained by a proteomic network response. Hence, we hypothesize the existence of a class of “balancer” proteins within the proteomic network, defined as proteins that buffer or cushion a system, and thus oppose multiple system disturbances. Through database queries and resilience analysis of the protein interaction network, we found that potential balancer proteins are of high cellular abundance, possess a low number of direct interaction partners, and show great allelic variation. Moreover, balancer proteins contribute more heavily to the network entropy, and thus are of high importance in terms of system resilience. We propose that the “elasticity” of the proteomic regulatory network mediated by balancer proteins may compensate for changes that occur under diseased conditions

Integration fluktuierender erneuerbarer Energien durch konvergente Nutzung von Strom- und Gasnetzen - Konvergenz Strom- und Gasnetze (KonStGas) - Abschlussbericht

Für die Energiewende in Deutschland ist zeitnah ein nennenswerter Ausbau der Stromnetze auf Transport- und Verteilnetzebene erforderlich. Mittel- bis langfristig werden für die Umstellung der Strom- und Energieversorgung auf erneuerbaren Energien (EE) zusätzlich große Speicherkapazitäten benötigt. Dabei sind kostengünstige und mit minimalen Energieverlusten verbundene Speicher- und Erzeugungstechnologien anzustreben. Lösungsansätze dafür werden bisher überwiegend auf der Stromseite diskutiert. Chancen, die sich aus der Kopplung von Strom- und Gasnetzen ergeben, werden kaum wahrgenommen. Das erhebliche Lösungspotential der vorhandenen Gasinfrastruktur und -Anwendungstechnologien mittels Power-to-Gas sowie die damit verbundenen Auswirkungen auf eine nachhaltige Gestaltung der Energiewende finden zu wenig Beachtung. Vor diesem Hintergrund hatte das Forschungsvorhaben "Integration fluktuierender erneuerbarer Energien durch konvergente Nutzung von Strom und Gasnetzen - Konvergenz Strom- und Gasnetze" zum Ziel, unter Berücksichtigung der Kopplung von Strom- und Gasnetzen, (1) die Potenziale zur Aufnahme, Speicherung und Verteilung von EE zu bestimmen, (2) die dynamischen Energieströme aus Angebot und Nachfrage in der gesamten Energieversorgungsstruktur zu modellieren, (3) die Kopplung volkswirtschaftlich zu analysieren und (4) Handlungsempfehlungen für den Ausbau der Netzinfrastrukturen und die Entwicklung eines zukünftigen Energiemarktes abzuleiten

Use of a genetically introduced cross-linker to identify interaction sites of acidic activators within native transcription factor IID and SAGA

An important goal is to identify the direct activation domain (AD)-interacting components of the transcriptional machinery within the context of native complexes. Toward this end, we first demonstrate that the multisubunit TFIID, SAGA, mediator, and Swi/Snf coactivator complexes from transcriptionally competent whole-cell yeast extracts were all capable of specifically interacting with the prototypic acidic ADs of Gal4 and VP16. We then used hexahistidine tags as genetically introduced activation domain-localized cross-linking receptors. In combination with immunological reagents against all subunits of TFIID and SAGA, we systematically identified the direct AD-interacting subunits within the AD-TFIID and AD-SAGA coactivator complexes enriched from whole-cell extracts and confirmed these results using purified TFIID and partially purified SAGA. Both ADs directly cross-linked to TBP and to a subset of TFIID and SAGA subunits that carry histone-fold motifs

Cloning of mouse ojoplano, a reticular cytoplasmic protein expressed during embryonic development

6 páginas, 4 figuras, 1 tabla de sequencia de datos (NCBI accession number EU683438).Ojoplano (Opo) is a morphogenetic gene playing an important role during embryogenesis in medaka. This report focuses on the identification and characterization of the mouse Opo gene. We examined Opo expression by whole-mount in situ hybridization and in situ hybridization on sagittal sections during mouse embryogenesis. First expression in whole-mounts was detected at Theiler stages 15–17 (E 9.5–10.5 dpc) as a spotted specific staining in migrating neural crest cells and in placodal structures. A complex expression pattern was observed in Theiler stage 22–23 (E 14.5 dpc) in sagittal sections, including expression in skeletal structures (skull, vertebrae, ribs, bones of the locomotor system), in the nasal region, the heart and the eye. Fusion proteins revealed the localization of OPO within the cytoplasm with a reticular distribution that largely overlapped with the endoplasmic reticulum. Opo shows homology to human transcripts linked to a hereditary craniofacial malformation, orofacial cleft 1 (OFC1). The expression of mouse Opo in neural crest derivatives and skull elements further supports this link.This work was supported by the Max Planck Society.Peer reviewe

Determination of anandamide and other fatty acyl ethanolamides in human serum by electrospray tandem mass spectrometry.

We developed a new selective liquid chromatography-electrospray ionization-tandem mass spectrometry method for the identification and quantification of anandamide (AEA), an endogenous cannabinoid receptor ligand, and other bioactive fatty acid ethanolamides (FAEs) in biological samples. Detection limit (0.025 pmol for AEA and 0.1 pmol for palmitoylethanolamide (PEA) and oleoylethanolamide (OEA)) and quantification limit (0.2 pmol for AEA and 0.4 pmol for OEA and PEA) were in the high fmol to low pmol range for all analytes. Linear correlations (r(2)=0.99) were observed in the calibration curves for standard AEA over the range of 0.025-25 pmol and for standard PEA and OEA over the range of 0.1-500 pmol. This method provides a time-saving and sensitive alternative to existing methods for the analysis of FAEs in biological samples

Anandamide levels in cerebrospinal fluid of first-episode schizophrenic patients: impact of cannabis use.

BackgroundPrevious studies have shown that cerebrospinal fluid (CSF) from schizophrenic patients contains significantly higher levels of the endogenous cannabinoid anandamide than does CSF from healthy volunteers. Moreover, CSF anandamide levels correlated inversely with psychotic symptoms, suggesting that anandamide release in the central nervous system (CNS) may serve as an adaptive mechanism countering neurotransmitter abnormalities in acute psychoses. In the present study we examined whether cannabis use may alter such a mechanism.MethodsWe used liquid chromatography/mass spectrometry (LC/MS) to measure anandamide levels in serum and CSF from first-episode, antipsychotic-naïve schizophrenics (n=47) and healthy volunteers (n=81). Based on reported patterns of cannabis use and urine delta9-tetrahydrocannabinol (delta9-THC) tests, each subject group was further divided into two subgroups: 'low-frequency' and 'high-frequency' cannabis users (lifetime use < or = 5 times and > 20 times, respectively). Serum delta9-THC was investigated to determine acute use and three patients were excluded from the analysis due to detectable delta9-THC levels in serum.ResultsSchizophrenic low-frequency cannabis users (n=25) exhibited > 10-fold higher CSF anandamide levels than did schizophrenic high-frequency users (n=19, p=0.008), healthy low-frequency (n=55, p<0.001) or high-frequency users (n=26, p<0.001). In contrast, no significant differences in serum anandamide levels were found among the four subgroups. CSF anandamide levels and disease symptoms were negatively correlated in both user groups.ConclusionsThe results indicate that frequent cannabis exposure may down-regulate anandamide signaling in the CNS of schizophrenic patients, but not of healthy individuals. Thus, our findings suggest that alterations in endocannabinoid signaling might be an important component of the mechanism through which cannabis impacts mental health

Current and future electron spectroscopy experiments in relativistic storage rings

Storage rings as the ESR and the future NESR in the FAIR project are unique tools to study the dynamics of electron-ion and ion-atom collisions in the realm of strong perturbations and short interaction times. A telling sign of the character of such collisions are the electrons emitted into the continuum. For high Z projectiles and low Z targets the projectile centred continuum is dominating. Precision studies of these electrons emitted in relativistic collisions thus are of paramount importance for an understanding of the ionization mechanisms active in transferring electrons into the continua. Forward electron spectroscopy thus appears to be the tool of choice. For high precision studies in collision spectroscopy of high Z projectiles we have implemented an imaging forward electron spectrometer into the ESR supersonic jet target zone. In combination with a reaction microscope to be implemented next this enables investigations of several fundamental processes ranging from kinematically complete studies of multiple ionization and (e, 2e) on ions to radiative and non-radiative electron transfer processes to the projectile continuum and for the first time kinematically complete measurements of the short-wavelength limit of the electron nucleus Bremsstrahlung. We report first results

Integration fluktuierender erneuerbarer Energien durch konvergente Nutzung von Strom- und Gasnetzen - Konvergenz Strom- und Gasnetze (KonStGas) : Abschlussbericht

Für die Energiewende in Deutschland ist zeitnah ein nennenswerter Ausbau der Stromnetze auf Transport- und Verteilnetzebene erforderlich. Mittel- bis langfristig werden für die Umstellung der Strom- und Energieversorgung auf erneuerbaren Energien (EE) zusätzlich große Speicherkapazitäten benötigt. Dabei sind kostengünstige und mit minimalen Energieverlusten verbundene Speicher- und Erzeugungstechnologien anzustreben. Lösungsansätze dafür werden bisher überwiegend auf der Stromseite diskutiert. Chancen, die sich aus der Kopplung von Strom- und Gasnetzen ergeben, werden kaum wahrgenommen. Das erhebliche Lösungspotential der vorhandenen Gasinfrastruktur und -Anwendungstechnologien mittels Power-to-Gas sowie die damit verbundenen Auswirkungen auf eine nachhaltige Gestaltung der Energiewende finden zu wenig Beachtung. Vor diesem Hintergrund hatte das Forschungsvorhaben "Integration fluktuierender erneuerbarer Energien durch konvergente Nutzung von Strom und Gasnetzen - Konvergenz Strom- und Gasnetze" zum Ziel, unter Berücksichtigung der Kopplung von Strom- und Gasnetzen, (1) die Potenziale zur Aufnahme, Speicherung und Verteilung von EE zu bestimmen, (2) die dynamischen Energieströme aus Angebot und Nachfrage in der gesamten Energieversorgungsstruktur zu modellieren, (3) die Kopplung volkswirtschaftlich zu analysieren und (4) Handlungsempfehlungen für den Ausbau der Netzinfrastrukturen und die Entwicklung eines zukünftigen Energiemarktes abzuleiten