Suche
Anzeige der Dokumente 1-10 von 16
Dissertation
Biochemical Characterization of Microtubule-Associated Serine/Threonine Kinases
(2023)
The association of human microtubule-associated serine/threonine (MAST) kinases with different diseases, such as neurodevelopmental disorders and cancer, leads to hight interest in understanding the function of these understudied kinases. This PhD thesis provides the first consolidated biochemical analysis of three different human MAST kinases (MAST1-3) and the Drosophila melanogaster homologue drop out protein (DOP).
Dissertation
Functional Analysis of Src42A in embryonic epithelial morphogenesis of Drosophila melanogaster
(2023)
Src42A is one of the Src family kinases (SFKs) present in Drosophila melanogaster. In mammals there are 8 SFKs and so far, a loss of function analysis of SFKs were difficult to conduct due to their functional redundancy. In Drosophila, there are only two SFKs namely Src42A and Src64B, the former is essential for embryonic development and the latter is a non-essential gene. Since Src42A is supplied as a maternal component, the zygotic mutant were showing defects in later developmental stages, because the contribution ...
Dissertation
![Open Access](/themes/Mirage2/images/Open_Access_logo_PLoS_transparent.svg)
Ash dieback : the pathogen Hymenoscyphus fraxineus and other fungi associated with stem collar necroses of common ash
(2024)
The ascomycete Hymenoscyphus fraxineus has caused devastating damage to the common ash (Fraxinus excelsior) in Europe in recent decades, resulting in considerable economic and ecological losses. The ash dieback pathogen is native to Asia, where it lives mainly as a saprobiont in peaceful coexistence with the Asian ash species Fraxinus mandshurica. Symptoms of the fungus in common ash include wilting of the leaves with subsequent dieback of shoots, twigs and branches, as well as damage to the stem base. These stem ...
Dissertation
Einfluss verschiedener Lipidstoffwechselwege auf die Entwicklung von Dictyostelium discoideum
(2024)
In den meisten Organismen spielen Lipid Droplets (LDs) eine positive Rolle beim Überleben einiger Stress-Bedingungen wie Nahrungsmangel. Axenisch wachsende D. discoideum haben keine LDs, sie sind „lean cells“, aber nach der Zugabe von 200 μM Palmitinsäure (PA) zum Kulturmedium synthetisieren die Zellen nach 3 h hunderte von LDs und werden zu „fat cells“. Überraschenderweise sterben die fat cells während der Nahrungsmangel-induzierten Entwicklung ab und bilden daher kaum Sporen. Neben dem Hauptneutrallipid Triacylglycerol ...
Dissertation
Regulatory mechanisms of Protein kinase A - Isoform mediated fine-tuning
(2023)
cAMP-dependent protein kinase (PKA) is a crucial part in eukaryotic signal transduction and controls biological processes. With a multitude of substrates, a great variety of cellular functions are regulated by PKA. Regulation of metabolism, cell growth and -differentiation, conductivity of ion channels, movement of sperm cells, embryonic development, neuroplasticity as well as conversion of short- to long-term memory are just examples for the many tasks of the kinase. To achieve and coordinate these diverse functions, ...
Dissertation
Pathogenic Mutations in Catalytic Subunit Isoforms of the cAMP-Dependent Protein Kinase
(2023)
Protein kinase A (PKA) is an integral part in a myriad of cellular pathways and a main effector of the second messenger cAMP. Since its discovery in the late 1960s, PKA has become one of the best-studied eukaryotic protein kinases in terms of enzymatic and structural features. Pathological implications of PKA have just started to emerge. There are three main isoforms (α, β, γ) of the catalytic subunit of PKA (PKA-C) which constitute a holoenzyme (R2C2) by association with a regulatory subunit (PKA-R) dimer. While ...
Dissertation
Functional analyses of Dph1•Dph2 in synthesis of diphthamide, a clinically relevant modification on eEF2
(2024)
Diphthamide is a unique post-translational modification of a conserved histidine on the eukaryotic translation elongation factor 2 (eEF2). During translation elongation, eEF2 induces translocation of codon-anticodon duplexes across the ribosomal decoding center. Diphthamide is involved in fine-tuning of this process by stabilizing the codon-anticodon duplex and maintaining reading frame accuracy. Initially, diphthamide was identified as the target for diphtheria toxin, enabling ADP-ribosylation of eEF2 and resulting ...
Dissertation
Nachweis und Analyse BamA-assoziierter Faltungsintermediate des OmpA durch ortsgerichtete Fluoreszenzspektroskopie
(2020-05)
Die Faltung und Insertion von Außenmembranproteinen (OMPs) in die Außenmembran von Gram negativen Bakterien ist für das Leben der Zellen essentiell und erfordert den konservierten β-barrel assembly machinery (BAM) Komplex. Zahlreiche Studien befassen sich mit der Aufklärung des dahinterstehenden Faltungsmechanismus von OMPs, doch bislang ist nur sehr wenig darüber bekannt. Daher steht der Faltungsmechanismus der spontanen Faltung und Insertion von OMPs wie OmpA und der Einfluss der BAM Hauptkomponente BamA darauf, ...
Dissertation
Association of neighboring β-Strands to form the β-barrel structure of the voltage-dependent anion channel, human isoform 1 (hVDAC1) precedes membrane insertion and is largely driven by polar interactions between basic and acidic amino acid side-chains
(2020)
To date, all biophysical folding studies on β-barrel membrane proteins from outer membranes (OMPs) indicated a coupled mechanism of folding and membrane insertion. Most of these studies were performed with smaller OMPs from bacteria. Here we have investigated folding and insertion of a mitochondrial OMP, the voltage-dependent anion-selective channel (VDAC), human isoform 1 (hVDAC1). To examine whether folding and insertion are coupled for hVDAC1, the association of neighboring β-strands of the 19-stranded β-barrel ...
Dissertation
Investigation of the functional synergy and involvement of different tRNA modifications in translational control
(2020-07-02)
Transfer RNAs are essential adapter molecules employed in the translational process and are highly modified all over their structure. Specific modification of the four canonical ribonucleotides (A, U, C, G) is accomplished by various proteins and/or protein complexes, ranging from simple isomerisations (e.g. Ψ) and methylations (e.g. m5C) up to complex chemical structures (e.g. mcm5s2U, ct6A). The functions of tRNA modifications are linked to the specific position and may influence translation by supporting the native ...