Peter Lanzerstorfer

• PhD
• Junior Group Leader | PostDoc Position at University of Applied Sciences Upper Austria

T cell receptor (TCR) clustering and formation of an immune synapse are crucial for TCR signaling. However, limited information is available about these dynamic assemblies and their connection to transmembrane signaling. In this work, TCR clustering is controlled via plug‐and‐play nanotools based on an engineered irreversible conjugation pair and a...

Mutations in the male germline are a driving force behind rare genetic diseases. Driver mutations enjoying a selective advantage expand to mutant clusters within the aged testis, and are thus overrepresented in sperm with age. Other kinds of driver mutations, occurring pre-pubescently, are the focus of recent attention given their high occurrence i...

The nanoscale arrangement of ligands can have a major effect on the activation of membrane receptor proteins and thus cellular communication mechanisms. Here we report on the technological development and use of tailored DNA origami-based molecular rulers to fabricate “Multiscale Origami Structures As Interface for Cells” (MOSAIC), to enable the sy...

Micropatterning in living cells is used for the analysis of protein-protein interactions. The quantitative analysis of images produced within this process is time-consuming and non-trivial task. For the simplification and speedup of such analyses, we describe a method for fully automated analysis of micro-patterned cells in fluorescence microscopy...

Membrane receptor clustering is fundamental to cell-cell communication; however, the physiological function of receptor clustering in cell signaling remains enigmatic. Here, we developed a dynamic platform to induce cluster formation of neuropeptide Y2 hormone receptors (Y2R) in situ by a chelator nanotool. The multivalent interaction enabled a dyn...

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. Abstract The incretin hormones: glucose-dependent insulinotropic po...

Polymeric materials play an emerging role in biosensing interfaces. Within this regard, polymers can serve as a superior surface for binding and printing of biomolecules. In this study, we characterized 11 different polymer foils [cyclic olefin polymer (COP), cyclic olefin copolymer (COC), polymethylmethacrylate (PMMA), DI-Acetate, Lumirror 4001, M...

News from an old acquaintance: The streptavidin (STV)‐biotin binding system is frequently used for the decoration of DNA origami nanostructures (DON) to study biological systems. Here, a surprisingly high dynamic of the STV/DON interaction is reported, which is affected by the structure of the DNA linker system. Analysis of different mono‐ or bi‐de...

At the plasma membrane of mammalian cells, major histocompatibility complex class I molecules (MHC-I) present antigenic peptides to cytotoxic T cells. Following the loss of the peptide and the light chain beta-2 microglobulin (β2m), the resulting free heavy chains (FHCs) can associate into homotypic complexes in the plasma membrane. Here, we invest...

Depositing biomolecule micropatterns on solid substrates via microcontact printing (µCP) usually requires complex chemical substrate modifications to initially create reactive surface groups. Here, we present a simplified activation procedure for untreated solid substrates based on a commercial polymer metal ion coating (AnteoBindTM Biosensor reage...

Postprandial insulin-stimulated glucose uptake into target tissue is crucial for the maintenance of normal blood glucose homeostasis. This step is rate-limited by the number of facilitative glucose transporters type 4 (GLUT4) present in the plasma membrane. Since insulin resistance and impaired GLUT4 translocation are associated with the developmen...

Membrane receptors are central to cell-cell communication. Receptor clustering at the plasma membrane modulates physiological responses, and microscale receptor organization is critical for downstream signaling. Spatially restricted cluster formation of the neuropeptide Y 2 hormone receptor (Y 2 R) was observed in vivo ; however, the relevance of t...

Analysis of protein–protein interactions in living cells by protein micropatterning is currently limited to the spatial arrangement of transmembrane proteins and their corresponding downstream molecules. Here, we present a robust and straightforward method for dynamic immunopatterning of cytosolic protein complexes by use of an artificial transmemb...

Bioactive plant compounds and extracts are of special interest for the development of pharmaceuticals. Here, we describe the screening of more than 1100 aqueous plant extracts and synthetic reference compounds for their ability to stimulate or inhibit insulin secretion. To quantify insulin secretion in living MIN6 β cells, an insulin-Gaussia lucife...

Previously, we demonstrated that major histocompatibility complex class I molecules (MHC-I) that lose the antigenic peptide and the light chain beta-2 microglobulin (β 2 m) to become free heavy chains (FHCs) associate to form dimers or higher-order oligomers in the plasma membrane (Dirscherl et al., 2018). Here, we investigate this homotypic intera...

Analysis of protein-protein interactions in living cells by protein micropatterning is currently limited to the spatial arrangement of transmembrane proteins and their corresponding downstream molecules. Here we present a robust method for visual immunoprecipitation of cytosolic protein complexes by use of an artificial transmembrane bait construct...

For probing small distances in living cells, methods of super-resolution microscopy and molecular sensing are reported. A main requirement is low light exposure to maintain cell viability and to avoid photobleaching of relevant fluorophores. From this point of view, Structured Illumination Microscopy (SIM), Axial Tomography, Total Internal Reflecti...

Major histocompatibility complex class I molecules (MHC I) that lose the antigenic peptide and the light chain beta-2 microglobulin (β2m) to become free heavy chains at the cell surface are known to associate, forming oligomers on the plasma membrane that are insufficiently understood. Here, we investigate the homotypic interaction of MHC I free he...

Essential oils (EOs) have attracted increased interest for different applications such as food preservatives, feed additives and ingredients in cosmetics. Due to their reported variable composition of components, they might be acutely toxic to humans and animals in small amounts. Despite the necessity, rigorous toxicity testing in terms of safety e...

Due to the global rise of type 2 diabetes mellitus (T2DM) in combination with insulin resistance, novel compounds to efficiently treat this pandemic disease are needed. Screening for compounds that induce the translocation of glucose transporter 4 (GLUT4) from the intracellular compartments to the plasma membrane in insulin-sensitive tissues is an...

Here, we present a simple and robust experimental setup for the super-resolution live cell microscopy of membrane-proximal fluorophores, which is comparably easy to perform and to implement. The method is based on Structured Illumination Microscopy (SIM) with a switchable spatial light modulator (SLM) and exchangeable objective lenses for epi-illum...

This study was conducted to examine putative correlations between weather parameters during April-September and the amounts of nutrients, minerals and bioactive compounds in the juices of 16 apple varieties from four harvest years in Lower Austria. For most sugar-parameters, negative correlations were found with the total precipitation (r between -...

Protein micropatterning is a powerful tool for spatial arrangement of transmembrane and intracellular proteins in living cells. The restriction of one interaction partner (the bait, e.g., the receptor) in regular micropatterns within the plasma membrane and the monitoring of the lateral distribution of the bait’s interaction partner (the prey, e.g....

The transport of hydrophobic compounds to recipient cells is a critical step in nutrient supplementation. Here, we tested the effect of phospholipid-based emulsification on the uptake of hydrophobic compounds into various tissue culture cell lines. In particular, the uptake of ω-3 fatty acids from micellar or nonmicellar algae oil into cell models...

An increase in adipose tissue is caused by the increased size and number of adipocytes. Lipids accumulate in intracellular stores, known as lipid droplets (LDs). Recent studies suggest that parameters such as LD size, shape and dynamics are closely related to the development of obesity. Berberine (BBR), a natural plant alkaloid, has been demonstrat...

Guava (Psidium guajava) fruit extract prepared by supercritical CO2 extraction inhibits intestinal glucose resorption in a double-blind, randomized clinical study

Pharmaceutical agents or drugs often have some pronounced impact on protein-protein interactions in cells and, in particular, cell membranes. Changes of molecular conformations as well as of intermolecular interactions may affect dipole-dipole interaction between chromophoric groups, which can be proven by measurements of Förster Resonance Energy T...

Mol. Nutr. Food Res. 2018, 62, 1701012 DOI: 10.1002/mnfr.201701012 Phytochemicals can directly affect intestinal glucose uptake by competitive inhibition of sugar transporters. Anti‐hyperglycemic properties have been so far reported for guava leaves, but there is little understanding of guava fruit extracts in this context. Therefore, the effects o...

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Abstract: Scope: Known pharmacological activities of guava (Psidium guajava) include modulation of blood glucose levels. However, mechanistic details remain unclear in many cases. Methods and results: This study investigated the effects of different guava leaf and fruit extracts on intestinal glucose transport in vitro and on postprandial glucose l...

Elevated blood glucose levels in type 2 diabetes mellitus (T2DM), a complex and multifactorial metabolic disease, are caused by insulin resistance and β-cell failure. Various strategies, including the injection of insulin or the usage of insulin-sensitizing drugs, were pursued to treat T2DM or at least reduce the symptoms. In addition, the applicat...

Insulin-like growth factor-I receptor (IGF-IR) preferentially regulates the long-term IGF activities including growth and metabolisms. Kinetics of ligand-dependent IGF-IR endocytosis determines how IGF induces such downstream signaling outputs. Here we find that the insulin receptor substrate (IRS)-1 modulates how long ligand-activated IGF-IR remai...

Postprandial hyperglycemia is a serious risk factor for cardiovascular disease and type 2 diabetes mellitus (T2DM). As diet is a cornerstone of both T2DM prevention and therapy, we investigated the effects of various commercially available breads on postprandial glucose response and glycemic index. Furthermore, the impact of oilseed- and protein-en...

Characterization, especially quantification, of protein interactions in live cells is usually not an easy endeavor. Here, we describe a straightforward method to identify and quantify the interaction of a membrane protein (“bait”) and a fluorescently labeled interaction partner (“prey”) (membrane-bound or cytosolic) in live cells using Total Intern...

Receptor-PI3K-mTORC1 signaling and fatty acid synthase (FASN)-regulated lipid biosynthesis harbor numerous drug targets and are molecularly connected. We hypothesize that unraveling the mechanisms of pathway cross-talk will be useful for designing novel co-targeting strategies for ovarian cancer (OC). The impact of receptor-PI3K-mTORC1 onto FASN is...

Background: Dietary inorganic nitrate (NO3−) and its reduced forms nitrite (NO2−) and nitric oxide (NO), respectively, are of critical importance for host defense in the oral cavity. High concentrations of salivary nitrate are linked to a lower prevalence of caries due to growth inhibition of cariogenic bacteria. Objective: In-vitro studies sugges...

Membrane-localized proteins are essential to transmit signals into the cell. An important issue is the interaction of these proteins with cytosolic proteins. To quantify such often short-lived interactions we have introduced a method based on the combination of micro-structured surfaces and TIRF microscopy (1,2).We have used the assay to validate t...

Induction of GLUT4 translocation in the absence of insulin is considered a key concept to decrease elevated blood glucose levels in diabetics. Due to the lack of pharmaceuticals that specifically increase the uptake of glucose from the blood circuit, application of natural compounds might be an alternative strategy. However, the effects and mechani...

Specificity of GFP-signal increase upon PP60 treatment. (A) CHO-K1 GPI-GFP cells were seeded in 96-well plates (35,000 cells/well), grown over night, and starved for 3 hours in HBSS buffer. Fluorescence intensity was measured before and after 10 minutes of stimulation with PP60 in the same cells (n > 200 cells). Scale bar = 20 μm. (B) Increase of G...

Effects of herbal compounds on actin remodeling. CHO-K1 hIR/GLUT4-myc-GFP cells were transiently transfected with the F-actin marker Lifeact-tdTomato, seeded in 96-well plates (100,000 cells/well), grown over night, and then starved for 3 hours in HBSS buffer. GLUT4-GFP and Lifeact-tdTomato signals recorded at 488 and 561 nm before and after stimul...

Background: Polyphenols are chemical compounds of the secondary plant metabolism. High concentrations can be found in various fruits including apples, berries and grapes. Polyphenols are associated with numerous health beneficial effects including a reduced risk for cardiovascular disease or diabetes. The human body cannot synthesize or store poly...

Background: Polyphenols are chemical compounds of the secondary plant metabolism. High concentrations can be found in various fruits including apples, berries and grapes. Polyphenols are associated with numerous health beneficial effects including a reduced risk for cardiovascular disease or diabetes. The human body cannot synthesize or store polyp...

Heuristic algorithms are used for solving numerous modern research questions in biomedical informatics. We here summarize ongoing research done in this context and focus on approaches used in the analysis of microscopic images of biological samples. On the one hand we discuss the use of evolutionary algorithms for detecting and classifying structur...

Beta vulgaris L. (beetroot) contains high amounts of biologically active substances including betalains and inorganic nitrate. We determined the amounts of various compounds (minerals, betalains, oxalic acid, phenolic acids, and sugars) in juice prepared from seven different beetroot varieties cultivated in Upper Austria. Large differences were fou...

Recent evidence suggests that activation of G protein-coupled receptors (GPCR), e.g. the β-adrenergic receptor (βAR), leads to transactivation of adjacent membrane receptors such as the epidermal growth factor receptor (EGFR) [1]. The process of GPCR-mediated receptor tyrosine kinase (RTK) transactivation is highly complex and appears to depend on...

Originally developed for application in micro-electronics, micro-patterning has spread over most areas of science, including biology. Micro-patterning allows for the specific design of cell micro-environment and now covers a large number of cell biology applications, from stem cell culture and differentiation to printing of purified proteins or oth...

Insulin receptor substrates (IRSs) are phosphorylated by activated insulin/insulin-like growth factor I receptor (IR/IGF-IR) tyrosine kinases, which is an initial key event for downstream signaling and bioactivities. Despite the structural similarities, increasing evidences show that IRS family proteins have non-redundant functions. Although the sp...

Background And Purpose: Insulin stimulates the transport of glucose in target tissues by triggering the translocation of glucose transporter 4 (GLUT4) to the plasma membrane. Resistance to insulin, the major abnormality in type 2 diabetes, results in a decreased GLUT4 translocation efficiency. Thus, special attention is drawn on the search for comp...

The identification of the epidermal growth factor receptor (EGFR) as an oncogene has led to the development of several anticancer therapeutics directed against this receptor tyrosine kinase. However, drug resistance and low efficacy remain a severe challenge, and have led to a demand for novel systems for an efficient identification and characteriz...

The compositional characteristics of untreated pure juice prepared from 88 apple varieties grown in the region of Eferding/Upper Austria were determined. Many of the analyzed varieties are non-commercial, old varieties not present in market. The aim of the study was to quantitate the mineral, phosphate, trace elements and polyphenolic content in or...

β-adrenergic (βAR) receptors belong to the class of G protein-coupled receptors (GPCRs) and generally administrate the physiological response of adrenaline and noradrenaline. They can be classified into three receptor subtypes (β1, β2, β3) which are major drug targets for some of the most commonly prescribed drugs in the history of medicine. The va...

Receptor tyrosine kinases (RTK)s are high-affinity cell surface receptors known to have a critical role in the development of many types of cancer. So far, approximately 20 different RTK classes have been identified. Among them the RTK class I (EGF receptor) and class I (Insulin receptor).We used an assay combining TIRF microscopy and micro-pattern...

The plasma-membrane of living cells is the major organelle for cellular signaling cascades. To warrant the diverse functions of a cell, communication between the cytoplasm and its organelles and the extracellular space is crucial. Thus, membrane-localized protein receptors activated by various messengers are key to transmit signals into the cell. D...