Stephan, Milena

[["dc.bibliographiccitation.firstpage","E2042"],["dc.bibliographiccitation.issue","30"],["dc.bibliographiccitation.journal","Proceedings of the National Academy of Sciences of the United States of America"],["dc.bibliographiccitation.lastpage","E2049"],["dc.bibliographiccitation.volume","109"],["dc.contributor.author","Krick, Roswitha"],["dc.contributor.author","Busse, Ricarda A."],["dc.contributor.author","Scacioc, Andreea"],["dc.contributor.author","Stephan, Milena"],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Thumm, Michael"],["dc.contributor.author","Kuehnel, Karin"],["dc.date.accessioned","2018-11-07T09:08:09Z"],["dc.date.available","2018-11-07T09:08:09Z"],["dc.date.issued","2012"],["dc.description.abstract","beta-propellers that bind polyphosphoinositides (PROPPINs), a eukaryotic WD-40 motif-containing protein family, bind via their predicted beta-propeller fold the polyphosphoinositides PtdIns3P and PtdIns(3,5) P-2 using a conserved FRRG motif. PROPPINs play a key role in macroautophagy in addition to other functions. We present the 3.0-angstrom crystal structure of Kluyveromyces lactis Hsv2, which shares significant sequence homologies with its three Saccharomyces cerevisiae homologs Atg18, Atg21, and Hsv2. It adopts a seven-bladed beta-propeller fold with a rare nonvelcro propeller closure. Remarkably, in the crystal structure, the two arginines of the FRRG motif are part of two distinct basic pockets formed by a set of highly conserved residues. In comprehensive in vivo and in vitro studies of ScAtg18 and ScHsv2, we define within the two pockets a set of conserved residues essential for normal membrane association, phosphoinositide binding, and biological activities. Our experiments show that PROPPINs contain two individual phosphoinositide binding sites. Based on docking studies, we propose a model for phosphoinositide binding of PROPPINs."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [SFB860]"],["dc.identifier.doi","10.1073/pnas.1205128109"],["dc.identifier.isi","000306992700006"],["dc.identifier.pmid","22753491"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/25961"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Natl Acad Sciences"],["dc.relation.issn","0027-8424"],["dc.title","Structural and functional characterization of the two phosphoinositide binding sites of PROPPINs, a beta-propeller protein family"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","770"],["dc.bibliographiccitation.issue","5"],["dc.bibliographiccitation.journal","Autophagy"],["dc.bibliographiccitation.lastpage","777"],["dc.bibliographiccitation.volume","9"],["dc.contributor.author","Busse, Ricarda A."],["dc.contributor.author","Scacioc, Andreea"],["dc.contributor.author","Hernandez, Javier M."],["dc.contributor.author","Krick, Roswitha"],["dc.contributor.author","Stephan, Milena"],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Thumm, Michael"],["dc.contributor.author","Kuehnel, Karin"],["dc.date.accessioned","2018-11-07T09:24:51Z"],["dc.date.available","2018-11-07T09:24:51Z"],["dc.date.issued","2013"],["dc.description.abstract","We characterized phosphoinositide binding of the S. cerevisiae PROPPIN Hsv2 qualitatively with density flotation assays and quantitatively through isothermal titration calorimetry (ITC) measurements using liposomes. We discuss the design of these experiments and show with liposome flotation assays that Hsv2 binds with high specificity to both PtdIns3P and PtdIns(3,5)P-2. We propose liposome flotation assays as a more accurate alternative to the commonly used PIP strips for the characterization of phosphoinositide-binding specificities of proteins. We further quantitatively characterized PtdIns3P binding of Hsv2 with ITC measurements and determined a dissociation constant of 0.67 mu M and a stoichiometry of 2:1 for PtdIns3P binding to Hsv2. PtdIns3P is crucial for the biogenesis of autophagosomes and their precursors. Besides the PROPPINs there are other PtdIns3P binding proteins with a link to autophagy, which includes the FYVE-domain containing proteins ZFYVE1/DFCP1 and WDFY3/ALFY and the PX-domain containing proteins Atg20 and Snx4/Atg24. The methods described could be useful tools for the characterization of these and other phosphoinositide-binding proteins."],["dc.description.sponsorship","[SFB860]"],["dc.identifier.doi","10.4161/auto.23978"],["dc.identifier.isi","000323174100012"],["dc.identifier.pmid","23445924"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/29929"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Landes Bioscience"],["dc.relation.issn","1554-8627"],["dc.title","Qualitative and quantitative characterization of protein-phosphoinositide interactions with liposome-based methods"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","106"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Autophagy"],["dc.bibliographiccitation.lastpage","107"],["dc.bibliographiccitation.volume","9"],["dc.contributor.author","Thumm, Michael"],["dc.contributor.author","Busse, Ricarda A."],["dc.contributor.author","Scacioc, Andreea"],["dc.contributor.author","Stephan, Milena"],["dc.contributor.author","Janshoff, Andreas"],["dc.contributor.author","Kuehnel, Karin"],["dc.contributor.author","Krick, Roswitha"],["dc.date.accessioned","2018-11-07T09:30:44Z"],["dc.date.available","2018-11-07T09:30:44Z"],["dc.date.issued","2013"],["dc.description.abstract","PROPPINs are a family of PtdIns3P and PtdIns(3,5) P-2-binding proteins. The crystal structure now unravels the presence of two distinct phosphoinositide-binding sites at the circumference of the seven bladed beta-propeller. Mutagenesis analysis of the binding sites shows that both are required for normal membrane association and autophagic activities. We identified a set of evolutionarily conserved basic and polar residues within both binding pockets, which are crucial for phosphoinositide binding. We expect that membrane association of PROPPINs is further stabilized by membrane insertions and interactions with other proteins."],["dc.identifier.doi","10.4161/auto.22400"],["dc.identifier.isi","000313077900012"],["dc.identifier.pmid","23069643"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/31376"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Landes Bioscience"],["dc.relation.issn","1554-8627"],["dc.title","It takes two to tango PROPPINs use two phosphoinositide-binding sites"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.subtype","letter_note"],["dspace.entity.type","Publication"]]