Publications by authors named "Olesya Shpironok"

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an endoplasmic reticulum (ER)-located protein with cytoprotective effects in neurons and pancreatic β cells in vitro and in models of neurodegeneration and diabetes in vivo. However, the exact mode of MANF action has remained elusive. Here, we show that MANF directly interacts with the ER transmembrane unfolded protein response (UPR) sensor IRE1α, and we identify the binding interface between MANF and IRE1α.

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In this work, we put forward a hypothesis about the decisive role of multivalent nonspecific interactions in the early stages of PML body formation. Our analysis of the PML isoform sequences showed that some of the PML isoforms, primarily PML-II, are prone to phase separation due to their polyampholytic properties and the disordered structure of their C-terminal domains. The similarity of the charge properties of the C-terminal domains of PML-II and PML-VI isoforms made it possible for the first time to detect migration of PML-VI from PML bodies to the periphery of the cell nucleus, similar to the migration of PML-II isoforms.

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Plant photobodies are the membrane-less organelles (MLOs) that can be generated by protein-protein interactions between active form of phytochrome B (phyB) and phytochrome-interacting factors (PIFs). These organelles regulate plant photomorphogenesis. In this study, we developed two chimeric proteins with fluorescent proteins, phyB fused to EGFP and PIF6 fused to mCherry, and investigated their exogenous expression in mammalian cells by confocal fluorescence microscopy.

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Biomarkers engineered on the basis of bacterial phytochromes with biliverdin IXα (BV) cofactor as a chromophore are increasingly used in cell biology and biomedicine, since their absorption and fluorescence spectra lie within the so-called optical "transparency window" of biological tissues. However, the quantum yield of BV fluorescence in these biomarkers does not exceed 0.145.

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Transcriptional regulation is a critical facet of cellular development controlled by numerous transcription factors, among which are E-proteins (E2A, HEB, and E2-2) that play important roles in lymphopoiesis. For example, primary hematopoietic cells immortalisation is promoted by interaction of the conserved PCET motif consisting of the Leu-X-X-Leu-Leu (LXXLL) and Leu-Asp-Phe-Ser (LDFS) sequences of the transactivation domains (AD1) of E-proteins with the KIX domain of CBP/p300 transcriptional co-activators. Earlier, it was shown that the LXXLL motif is essential for the PCET-KIX interaction driven by the PCET helical transition.

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