Künstlerisches Forschen im Rahmen dreier Installationen für den Workshop Vom Seelengefährt zum Glorienleib

Wenn Licht auf einen Gegenstand trifft, hängt es von der Beschaffenheit des Gegenstands ab, wie sich das Licht verhält, ob es sich bricht, reflektiert wird oder durch den Gegenstand hindurchgeht. In philosophischen Zusammenhängen wird die Wirkweise des Lichts häufig in metaphorischer Weise dafür herangezogen, Erkenntnisprozesse zu beschreiben. Antike und neuzeitliche Vorstellungen davon, wie Seele und Körper zusammenhängen, bei denen es u. a. darum geht, wie Erkennen und Wahrnehmen zusammenhängen, nehmen häufig Analogie und Bilder der Wirkweise von Licht auf. Die Thematik der Beschaffenheit von Licht, wie sie in den Installationen verarbeitet wurde, sollte ein anderes Nachdenken über die Rolle des Seelenleibs, der zwischen Materialität und Immaterialität steht, anregen und ermöglichen. Der Prozess der Auseinandersetzung mit der Thematik von Seelen-leib und Lichttheorien in der Antike, der in der Vorbereitung der Installationen geleistet wurde, wie auch die Installationen selbst sind dabei Beispiele für künstlerisches Forschen

FC2 stabilizes POR and suppresses ALA formation in the tetrapyrrole biosynthesis pathway

During photoperiodic growth, the light-dependent nature of chlorophyll synthesis in angiosperms necessitates robust control of the production of 5-aminolevulinic acid (ALA), the rate-limiting step in the initial stage of tetrapyrrole biosynthesis (TBS). We are interested in dissecting the post-translational control of this process, which suppresses ALA synthesis for chlorophyll synthesis in dark-grown plants. Using biochemical approaches for analysis of Arabidopsis wild-type (WT) and mutant lines as well as complementation lines, we show that the heme-synthesizing ferrochelatase 2 (FC2) interacts with protochlorophyllide oxidoreductase and the regulator FLU which both promote the feedback-controlled suppression of ALA synthesis by inactivation of glutamyl-tRNA reductase, thus preventing excessive accumulation of potentially deleterious tetrapyrrole intermediates. Thereby, FC2 stabilizes POR by physical interaction. When the interaction between FC2 and POR is perturbed, suppression of ALA synthesis is attenuated and photoreactive protochlorophyllide accumulates. FC2 is anchored in the thylakoid membrane via its membrane-spanning CAB (chlorophyll-a-binding) domain. FC2 is one of the two isoforms of ferrochelatase catalyzing the last step of heme synthesis. Although FC2 belongs to the heme-synthesizing branch of TBS, its interaction with POR potentiates the effects of the GluTR-inactivation complex on the chlorophyll-synthesizing branch and ensures reciprocal control of chlorophyll and heme synthesis.Chinese Scholarship CouncilDeutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Peer Reviewe

The WD40-Protein PfWLP1 Ensures Stability of the PfCCp-Based Adhesion Protein Complex in Plasmodium falciparum Gametocytes

Members of the WD40-repeat protein family can be found in all eukaryotic proteomes where they usually serve as interaction platforms for the assembly of large protein complexes and are therefore essential for the integrity of these complexes. In the malaria parasite Plasmodium falciparum, the WD40-repeat protein PfWLP1 has been shown to interact with members of distinct adhesion protein complexes in the asexual blood stages and gametocyte stages. In this study, we demonstrate that the presence of PfWLP1 is crucial for both the stability of these gametocyte-specific adhesion complexes as well as for gametocyte maturation and gametogenesis. Using reverse genetics, we generated a PfWLP1-knockdown parasite line for functional characterization of the protein. Knockdown of PfWLP1 resulted in a slight reduction of gametocyte numbers and significantly the impaired ability of the gametocytes to exflagellate. PfWLP1-knockdown further led to reduced protein levels of the Limulus coagulation factor C-like (LCCL)-domain proteins PfCCp1 and PfCCp2, which are key components of the adhesion complexes. These findings suggest that the interaction of PfWLP1 with members of the PfCCp-based adhesion complex ensures complex stability and thereby contributes to gametocyte viability and exflagellation

Investigating the importance of exported proteins for survival and host cell modification in asexual blood stages of Plasmodium falciparum

The malaria parasite Plasmodium falciparum has a unique, complex life cycle and exports a variety of proteins into the erythrocyte to alter the physiological properties of its host cell. These modifications are crucial for survival and render the parasite a master of immune evasion, which is one of the main reasons why there has not been developed an efficient vaccine to eradicate this devastating disease. Many exported proteins are thought to play a crucial role in protein export and host cell modifications. However, scientific breakthroughs in this field were hampered due to a lack of efficient genetic systems for the blood stages of the parasite. Over the last years, several new genetic tools were established for P. falciparum that allow the investigation of essential genes. In this study, four predicted essential proteins were analyzed using the glmS ribozyme system, an inducible knockdown method on mRNA level that is activated by glucosamine-6-phosphate. Coupled with selection-linked integration (SLI), it allows faster generation of transgenic cell lines than conventional subcloning methods. The glmS system worked efficiently in all cell lines studied with significant downregulation of the proteins of interest with 2.5 mM glucosamine. Concerning the development and morphology of the parasites, there was no growth defect observed via microscopy or SybrGreen-based growth assays. PF3D7_0220300 and PF3D7_0220600 are predicted to be membrane-bound proteins partly co-localizing with the Maurer’s clefts marker SBP1, and the erythrocyte membrane, respectively. PF3D7_0113300 and PF3D7_0301600 are predicted to be soluble proteins with the second partly co-localizing with SBP1. Using an in vitro static cytoadherence assay, I could show that binding to chondroitin sulfate A was significantly reduced in all cell lines except CS2PF3D7_0113300glmS with the strongest effect observed upon downregulation of PF3D7_0301600 and PF3D7_0220300. Quantification of the mean fluorescence intensities of PfEMP1 VAR2CSA via flow cytometry only showed significantly less signal after downregulation of PF3D7_0220300, further demonstrating the importance of the studied exported proteins in host cell modification, specifically cytoadherence and presentation of PfEMP1 on knobs. These results should be further investigated to get a more comprehensive understanding of the parasites’ biology. Moreover, inducible knockout systems using a dimerizable Cre recombinase could circumvent some disadvantages of the glmS system resulting from remaining protein levels or the cytotoxicity of glucosamine and should be considered in further studies

A cis-regulatory sequence from a short intergenic region gives rise to a strong microbe-associated molecular pattern-responsive synthetic promoter.

The high gene density in Arabidopsis thaliana leaves only relatively short intergenic regions for potential cis-regulatory sequences. To learn more about the regulation of genes harbouring only very short upstream intergenic regions, this study investigates a recently identified novel microbe-associated molecular pattern (MAMP)-responsive cis-sequence located within the 101 bp long intergenic region upstream of the At1g13990 gene. It is shown that the cis-regulatory sequence is sufficient for MAMP-responsive reporter gene activity in the context of its native promoter. The 3' UTR of the upstream gene has a quantitative effect on gene expression. In context of a synthetic promoter, the cis-sequence is shown to achieve a strong increase in reporter gene activity as a monomer, dimer and tetramer. Mutation analysis of the cis-sequence determined the specific nucleotides required for gene expression activation. In transgenic A. thaliana the synthetic promoter harbouring a tetramer of the cis-sequence not only drives strong pathogen-responsive reporter gene expression but also shows a high background activity. The results of this study contribute to our understanding how genes with very short upstream intergenic regions are regulated and how these regions can serve as a source for MAMP-responsive cis-sequences for synthetic promoter design

Influence of patients’ preoperative expectations on postoperative outcomes after total knee or hip arthroplasty: a systematic review

Purpose: The association between preoperative expectations and treatment outcomes in total hip arthroplasty (THA) or total knee arthroplasty (TKA) is still unclear. Therefore the aim is to examine the association between preoperative outcome expectations, process expectations, and self-efficacy, and the postoperative outcomes overall outcome, pain, function, stiffness, satisfaction, and quality of life following THA/TKA. Methods: A systematic review with narrative synthesis was conducted. PubMed, EMBASE, PsycINFO, CINAHL and Cochrane Library were searched from inception to October 17, 2022. Included were prospective longitudinal cohort studies published in English, German, or Dutch, with an adult population undergoing THA/TKA, and including at least one measure of preoperative expectations and the postoperative outcomes mentioned earlier. Two independent reviewers screened the retrieved articles for eligibility, a third solved disagreements. Risk of bias (RoB) was assessed using the QUIPS tool. Results: Of the 50 included studies, 38 had high RoB and 12 moderate RoB. Unadjusted results suggest a positive association between preoperative outcome expectations and overall outcome in the medium and long term, and between self-efficacy and change in ‘overall outcome’ in the long term. Adjusted results suggest positive associations between outcome expectations and function and between self-efficacy and overall outcome in the medium term, and for outcome expectations with pain and change in pain, respectively, and self-efficacy and stiffness in the long term. Conclusions: Preoperative expectations show a possible positive association with specific outcome measures, such as pain or function. For future research, it is advised to link matching specific expectations with specific outcomes

Vom Seelengefährt zum Glorienleib

Das Konzept des Seelengefährts, das bereits von Platon und zuvor von Parmenides konzipiert wurde, ist für die philosophische Selbstverständigung von der Antike bis in die frühe Auklärung und darüber hinaus die moderne Esoterik von zentraler Bedeutung. Sein veranschaulichendes Potenzial reicht von der Erkundung der Möglichkeiten der Kommunikation zwischen eigentlich klar voneinander geschiedenen ontologischen Räumen – dem des Unstofflich-Göttlichen einerseits und dem des Stofflich-Irdischen bzw. menschlich Seelischen andererseits – bis hin zu naturphilosophischen Entwürfen zur Erklärung des Phänomens der Elektrizität. Immer wieder wurde es von so unterschiedlichen Denkern wie z. B. Plutarch, Bernardus Silvestris, Kepler, Suarez oder Christian Wolf herangezogen, um das Problem der Einwirkung des Intelligiblen und Göttlichen auf die menschliche Seele oder die irdische Natur zu erklären. Es motivierte Dichter wie Traherne oder Donne zu literarischen Inszenierungen sympathetisch-aitherischer Leiblichkeit und deren eschatologischen Implikationen. Diesem zentralen und spannungsvollen Themenspektrum in seiner historischen wie thematischen Kontinuität nähern sich die Autor*innen dieses Bandes aus interdisziplinär verschränkter Perspektive, die zudem eine innovative, künstlerische Auseinandersetzung mit den verschiedenen Aspekten des Licht(-leib)es umfasst