36 research outputs found
Revision der Gattung Dichodontium (Musci, Dicranaceae)
The eight species so far comprised in the genus Dichodondium are reduced to three. Dichodontium verrucosum Card. is regarded as conspecific with D. pellucidum ( Hedw.) Schimp. Dichodontium opacifolium Dix. is regarded as conspecific with D. brasiliense Broth. The placement of this species in the genus Dichodontium is doubtful. Dichodontium nelsonii Kindb. proved to be Bartramia pomiformis Hedw. Dichodontium debile Broth. and D. integrum Sak. remain dubious species because of a lack of type material and references. Dichodontium pellucidum (Hedw.) Schimp. is lectotypified.Die 8 bisher in der Gattung Dichodontium eingeschlossenen Arten werden auf 3 reduziert. Dichodontium verrucosum Card. ist synonym mit D. pellucidum (Hedw.) Schimp. Dichodontium opacifolium Dix. ist synonym mit D. brasiliense Broth., wobei die Zugehörigkeit dieser Art zur Gattung Dichodontium nicht vollkommen geklärt ist. Dichodontium nelsonii Kindb. stellte sich als Bartramia pomiformis Hedw. heraus. Dichodontium debile Broth. und D. integrum Sak. bleiben aufgrund von fehlendem Typusmaterial unrevidiert. Dichodontium pellucidum (Hedw.) Schimp. wird lektotypifiziert
The MECP2‐TRD domain interacts with the DNMT3A‐ADD domain at the H3‐tail binding site
The DNMT3A DNA methyltransferase and MECP2 methylation reader are highly expressed in neurons. Both proteins interact via their DNMT3A‐ADD and MECP2‐TRD domains, and the MECP2 interaction regulates the activity and subnuclear localization of DNMT3A. Here, we mapped the interface of both domains using peptide SPOT array binding, protein pull‐down, equilibrium peptide binding assays, and structural analyses. The region D529‐D531 on the surface of the ADD domain was identified as interaction point with the TRD domain. This includes important residues of the histone H3 N‐terminal tail binding site to the ADD domain, explaining why TRD and H3 binding to the ADD domain is competitive. On the TRD domain, residues 214-228 containing K219 and K223 were found to be essential for the ADD interaction. This part represents a folded patch within the otherwise largely disordered TRD domain. A crystal structure analysis of ADD revealed that the identified H3/TDR lysine binding pocket is occupied by an arginine residue from a crystallographic neighbor in the ADD apoprotein structure. Finally, we show that mutations in the interface of ADD and TRD domains disrupt the cellular interaction of both proteins in NIH3T3 cells. In summary, our data show that the H3 peptide binding cleft of the ADD domain also mediates the interaction with the MECP2‐TRD domain suggesting that this binding site may have a broader role also in the interaction of DNMT3A with other proteins leading to complex regulation options by competitive and PTM specific binding.Helmholtz‐Zentrum BerlinDeutsche ForschungsgemeinschaftProjekt DEA
Occurrence and conversion of progestogens and androgens are conserved in land plants
Summary Progestogens and androgens have been found in many plants, but little is known about their biosynthesis and the evolution of steroidogenesis in these organisms. Here, we show that the occurrence and biosynthesis of progestogens and androgens are conserved across the viridiplantae lineage. An UHPLC‐ESI‐MS/MS method allowed high‐throughput analysis of the occurrence and chemical conversion of progestogens and androgens in 41 species across the green plant lineage. Dehydroepiandrosterone, testosterone, and 5α‐dihydrotestosterone are plants' most abundant mammalian‐like steroids. Progestogens are converted into 17α‐hydroxyprogesterone and 5α‐pregnane‐3,20‐dione. Androgens are converted into testosterone and 5α‐dihydrotestosterone. 17,20‐Lyases, essential for converting progestogens to androgens, seem to be most effective in monocot species. Our data suggest that the occurrence of progestogens and androgens is highly conserved in plants, and their biosynthesis might favor a route using the Δ4 pathway. </p
SETDB1 Is Involved in Postembryonic DNA Methylation and Gene Silencing in Drosophila
DNA methylation is fundamental for the stability and activity of genomes. Drosophila melanogaster and vertebrates establish a global DNA methylation pattern of their genome during early embryogenesis. Large-scale analyses of DNA methylation patterns have uncovered revealed that DNA methylation patterns are dynamic rather than static and change in a gene-specific fashion during development and in diseased cells. However, the factors and mechanisms involved in dynamic, postembryonic DNA methylation remain unclear. Methylation of lysine 9 in histone H3 (H3-K9) by members of the Su(var)3–9 family of histone methyltransferases (HMTs) triggers embryonic DNA methylation in Arthropods and Chordates. Here, we demonstrate that Drosophila SETDB1 (dSETDB1) can mediate DNA methylation and silencing of genes and retrotransposons. We found that dSETDB1 tri-methylates H3-K9 and binds methylated CpA motifs. Tri-methylation of H3-K9 by dSETDB1 mediates recruitment of DNA methyltransferase 2 (Dnmt2) and Su(var)205, the Drosophila ortholog of mammalian “Heterochromatin Protein 1”, to target genes for dSETDB1. By enlisting Dnmt2 and Su(var)205, dSETDB1 triggers DNA methylation and silencing of genes and retrotransposons in Drosophila cells. DSETDB1 is involved in postembryonic DNA methylation and silencing of Rt1b{} retrotransposons and the tumor suppressor gene retinoblastoma family protein 1 (Rb) in imaginal discs. Collectively, our findings implicate dSETDB1 in postembryonic DNA methylation, provide a model for silencing of the tumor suppressor Rb, and uncover a role for cell type-specific DNA methylation in Drosophila development
Mobility in a Globalised World 2012
The term mobility has different meanings in the following science disciplines. In economics,
mobility is the ability of an individual or a group to improve their economic status in relation
to income and wealth within their lifetime or between generations. In information systems and
computer science, mobility is used for the concept of mobile computing, in which a computer
is transported by a person during normal use. By designing logistics networks, logistics creates
the infrastructure for the mobility of people and goods. Electric mobility is one of today’s
solutions from an engineering perspective to the problem of reducing the need for energy resources
and environmental impact. Finally, for urban planning, mobility is the crunch question
as to how to optimise the different needs for mobility and how to link different transportation
systems. In this publication we have collected the ideas of practitioners, researchers, and government officials about the different modes of mobility in a globalised world, focusing on both domestic and international issues
Risk governance in organizations
Dieses Buch dokumentiert 10 Jahre Risk-Governance-Forschung an der Universität Siegen. In 50 Beiträgen reflektieren Forscher und Praktiker Risk Governance vor dem Hintergrund ihrer eigenen Forschungen und/oder Erfahrungen und geben jeweils einen Entwicklungsimpuls für die Zukunft der Risk Governance. Das Buch zeigt die große Bandbreite und Tiefe des Forschungsgebietes auf und diskutiert Grundannahmen, Implementierungsfragen, die Rolle der Risk Governance als Transformationsmotor, ihre Wirkung in den verschiedenen betrieblichen Funktionen, Entwicklungsperspektiven und den Beitrag der Risk Governance zu einer nachhaltigen Ausrichtung von Unternehmen.This book documents 10 years of risk governance research at the University of Siegen. In 50 contributions, researchers and practitioners reflect on risk governance against the background of their own research and/or experience and provide a development impetus for the future of risk governance. The book shows the wide range and depth of the research field and discusses basic assumptions, implementation issues, the role of risk governance as transformation engine, its impact in the various operational functions, development perspectives, and the contribution of risk governance to a sustainable orientation of companies
DNA methylation and methyl-CpG binding proteins: developmental requirements and function
DNA methylation is a major epigenetic modification in the genomes of higher eukaryotes. In vertebrates, DNA methylation occurs predominantly on the CpG dinucleotide, and approximately 60% to 90% of these dinucleotides are modified. Distinct DNA methylation patterns, which can vary between different tissues and developmental stages, exist on specific loci. Sites of DNA methylation are occupied by various proteins, including methyl-CpG binding domain (MBD) proteins which recruit the enzymatic machinery to establish silent chromatin. Mutations in the MBD family member MeCP2 are the cause of Rett syndrome, a severe neurodevelopmental disorder, whereas other MBDs are known to bind sites of hypermethylation in human cancer cell lines. Here, we review the advances in our understanding of the function of DNA methylation, DNA methyltransferases, and methyl-CpG binding proteins in vertebrate embryonic development. MBDs function in transcriptional repression and long-range interactions in chromatin and also appear to play a role in genomic stability, neural signaling, and transcriptional activation. DNA methylation makes an essential and versatile epigenetic contribution to genome integrity and function
Design and solution of insular solar system for family house for condition of Czech republic
Bakalářská práce se zaměřuje na čerpání energie z obnovitelných zdrojů, konkrétně na energii ze slunečního záření. V práci je přiblížen způsob získávání této energie a její přeměny na energii elektrickou. Následně je navržena fotovoltaická elektrárna pro rodinný dům v České republice. Jedná se o OFF GRID hybridní elektrárnu s využitím přebytků pro ohřev vody a vytápění elektrickým bojlerem. Obsahuje elektroinstalační schéma a zabývá se možností dotace.The bachelor thesis is focused on getting energy from renewable sources, specifically on the extraction energy from sunshine. The work describes the metod how is the energy obtained and converted into electrical energy. Then, a photovoltaic power plant for family house in the Czech Republic is designed. It is OFF GRID hybrid power plant with the use of surpluses for watter heating and heating using elecrical boiler. It contains an electrical installation diagram and deals with the possibility of a grant.