@article{TzonevaStoyanovaPetrichetal.2020, author = {Tzoneva, Rumiana and Stoyanova, Tihomira and Petrich, Annett and Popova, Desislava and Uzunova, Veselina and Momchilova, Albena and Chiantia, Salvatore}, title = {Effect of Erufosine on Membrane Lipid Order in Breast Cancer Cell Models}, series = {Biomolecules}, volume = {10}, journal = {Biomolecules}, number = {5}, publisher = {MDPI}, address = {Basel}, issn = {2218-273X}, doi = {10.3390/biom10050802}, pages = {17}, year = {2020}, abstract = {Alkylphospholipids are a novel class of antineoplastic drugs showing remarkable therapeutic potential. Among them, erufosine (EPC3) is a promising drug for the treatment of several types of tumors. While EPC3 is supposed to exert its function by interacting with lipid membranes, the exact molecular mechanisms involved are not known yet. In this work, we applied a combination of several fluorescence microscopy and analytical chemistry approaches (i.e., scanning fluorescence correlation spectroscopy, line-scan fluorescence correlation spectroscopy, generalized polarization imaging, as well as thin layer and gas chromatography) to quantify the effect of EPC3 in biophysical models of the plasma membrane, as well as in cancer cell lines. Our results indicate that EPC3 affects lipid-lipid interactions in cellular membranes by decreasing lipid packing and increasing membrane disorder and fluidity. As a consequence of these alterations in the lateral organization of lipid bilayers, the diffusive dynamics of membrane proteins are also significantly increased. Taken together, these findings suggest that the mechanism of action of EPC3 could be linked to its effects on fundamental biophysical properties of lipid membranes, as well as on lipid metabolism in cancer cells.}, language = {en} } @article{PetrichDunsingBoboneetal.2021, author = {Petrich, Annett and Dunsing, Valentin and Bobone, Sara and Chiantia, Salvatore}, title = {Influenza A M2 recruits M1 to the plasma membrane}, series = {Biophysical journal : BJ / ed. by the Biophysical Society}, volume = {120}, journal = {Biophysical journal : BJ / ed. by the Biophysical Society}, number = {24}, publisher = {Cell Press}, address = {Cambridge}, issn = {0006-3495}, doi = {10.1016/j.bpj.2021.11.023}, pages = {5478 -- 5490}, year = {2021}, abstract = {Influenza A virus (IAV) is a respiratory pathogen that causes seasonal epidemics with significant mortality. One of the most abundant proteins in IAV particles is the matrix protein 1 (M1), which is essential for the virus structural stability. M1 organizes virion assembly and budding at the plasma membrane (PM), where it interacts with other viral components. The recruitment of M1 to the PM as well as its interaction with the other viral envelope proteins (hemagglutinin [HA], neuraminidase, matrix protein 2 [M2]) is controversially discussed in previous studies. Therefore, we used fluorescence fluctuation microscopy techniques (i.e., scanning fluorescence cross-correlation spectroscopy and number and brightness) to quantify the oligomeric state of M1 and its interactions with other viral proteins in co-transfected as well as infected cells. Our results indicate that M1 is recruited to the PM by M2, as a consequence of the strong interaction between the two proteins. In contrast, only a weak interaction between M1 and HA was observed. M1-HA interaction occurred only in the event that M1 was already bound to the PM. We therefore conclude that M2 initiates the assembly of IAV by recruiting M1 to the PM, possibly allowing its further interaction with other viral proteins.}, language = {en} } @article{FangHolzmuellerMatulaitisetal.2016, author = {Fang, Lijia and Holzmueller, Felix and Matulaitis, Tomas and Baasner, Anne and Hauenstein, Christoph and Benduhn, Johannes and Schwarze, Martin and Petrich, Annett and Piersimoni, Fortunato and Scholz, Reinhard and Zeika, Olaf and Koerner, Christian and Neher, Dieter and Vandewal, Koen and Leo, Karl}, title = {Fluorine-containing low-energy-gap organic dyes with low voltage losses for organic solar cells}, series = {Synthetic metals : the journal of electronic polymers and electronic molecular materials}, volume = {222}, journal = {Synthetic metals : the journal of electronic polymers and electronic molecular materials}, publisher = {Elsevier}, address = {Lausanne}, issn = {0379-6779}, doi = {10.1016/j.synthmet.2016.10.025}, pages = {232 -- 239}, year = {2016}, abstract = {Fluorine-containing donor molecules TFTF, CNTF and PRTF are designed and isomer selectively synthesized for application in vacuum-deposited organic solar cells. These molecules comprise a donor acceptor molecular architecture incorporating thiophene and benzothiadiazole derivatives as the electron-donating and electron-withdrawing moieties, respectively. As opposed to previously reported materials from this class, PRTF can be purified by vacuum sublimation at moderate to high yields because of its higher volatility and better stabilization due to a stronger intramolecular hydrogen bond, as compared to TFTF and CNTF. The UV-vis absorption spectra of the three donors show an intense broadband absorption between 500 nm and 800 nm with, similar positions of their frontier energy levels. The photophysical properties of the three donor molecules are thoroughly tested and optimized in bulk heterojunction solar cells with C-60 as acceptor. PRTF shows the best performance, yielding power conversion efficiencies of up to 3.8\%. Moreover, the voltage loss for the PRTF device due to the non radiative recombination of free charge carriers is exceptionally low (0.26 V) as compared to typical values for organic solar cells (>0.34V). (C) 2016 Published by Elsevier B.V.}, language = {en} } @article{DunsingPetrichChiantia2021, author = {Dunsing, Valentin and Petrich, Annett and Chiantia, Salvatore}, title = {Multicolor fluorescence fluctuation spectroscopy in living cells via spectral detection}, series = {eLife}, volume = {10}, journal = {eLife}, publisher = {eLife Sciences Publications}, address = {Cambridge}, issn = {2050-084X}, doi = {10.7554/eLife.69687}, pages = {33}, year = {2021}, abstract = {Signaling pathways in biological systems rely on specific interactions between multiple biomolecules. Fluorescence fluctuation spectroscopy provides a powerful toolbox to quantify such interactions directly in living cells. Cross-correlation analysis of spectrally separated fluctuations provides information about intermolecular interactions but is usually limited to two fluorophore species. Here, we present scanning fluorescence spectral correlation spectroscopy (SFSCS), a versatile approach that can be implemented on commercial confocal microscopes, allowing the investigation of interactions between multiple protein species at the plasma membrane. We demonstrate that SFSCS enables cross-talk-free cross-correlation, diffusion, and oligomerization analysis of up to four protein species labeled with strongly overlapping fluorophores. As an example, we investigate the interactions of influenza A virus (IAV) matrix protein 2 with two cellular host factors simultaneously. We furthermore apply raster spectral image correlation spectroscopy for the simultaneous analysis of up to four species and determine the stoichiometry of ternary IAV polymerase complexes in the cell nucleus.}, language = {en} }