A5069661962- Autophagy in Disease and Therapy
- Endoplasmic Reticulum Stress and Disease
- Cellular transport and secretion
- Fungal and yeast genetics research
- Ubiquitin and proteasome pathways
- Polyamine Metabolism and Applications
- Studies on Chitinases and Chitosanases
- RNA Interference and Gene Delivery
- Metabolism, Diabetes, and Cancer
- Lysosomal Storage Disorders Research
- Nuclear Structure and Function
- Peptidase Inhibition and Analysis
- RNA modifications and cancer
- Plant responses to water stress
- Toxoplasma gondii Research Studies
- Cannabis and Cannabinoid Research
- Signaling Pathways in Disease
- Peroxisome Proliferator-Activated Receptors
- Mitochondrial Function and Pathology
- Lipid Membrane Structure and Behavior
- Lipid metabolism and biosynthesis
- Biochemical and Molecular Research
- Cancer, Hypoxia, and Metabolism
- RNA and protein synthesis mechanisms
- Enzyme function and inhibition
University of Göttingen
2011-2024
Universitätsmedizin Göttingen
2016-2021
University of Michigan
2012
UiT The Arctic University of Norway
2012
Washtenaw Community College
2012
Nephrologisches Zentrum Goettingen
2011
Biologie Labor
2011
University of Stuttgart
1995-2008
University of Tübingen
2008
Friedrich-Alexander-Universität Erlangen-Nürnberg
1993
Protein degradation in the vacuole (lysosome) is an important event cellular regulation. In yeast, as mammalian cells, a major route of protein uptake for into has been found to be autophagocytosis. The discovery this process yeast enables elucidation its mechanisms via genetic and molecular biological investigations. Here we report isolation mutants defective autophagocytosis ( aut mutants), using rapid colony screening procedure.
The study of autophagy is rapidly expanding, and our knowledge the molecular mechanism its connections to a wide range physiological processes has increased substantially in past decade. vocabulary associated with grown concomitantly. In fact, it difficult for readers--even those who work field--to keep up ever-expanding terminology various autophagy-related processes. Accordingly, we have developed comprehensive glossary terms that meant provide quick reference researchers need brief...
We have explored the phenotypic and genetic overlap between autophagocytosis cytoplasm to vacuole targeting in yeast Saccharomyces cerevisiae. Complementation analysis was performed with mutants each of these groups (aut cvt, respectively), three complementation were found overlap. Also, most unique aut accumulated precursor aminopeptidase I cytoplasm, while maintaining wild type kinetics maturation proteins targeted via secretory pathway. The majority non-overlapping cvt be at least...
ABSTRACT Selective disintegration of membrane-enclosed autophagic bodies is a feature eukaryotic cells not studied in detail. Using Saccharomyces cerevisiae mutant defective autophagic-body breakdown, we identified and characterized Aut5p, glycosylated integral membrane protein. Site-directed mutagenesis demonstrated the relevance its putative lipase active-site motif for breakdown. aut5 Δ show reduced protein turnover during starvation are maturation proaminopeptidase I. Most recently, by...
Autophagy is a diverse family of processes that transport cytoplasm and organelles into the lysosome/vacuole lumen for degradation. During macroautophagy cargo packaged in autophagosomes fuse with lysosome/vacuole. microautophagy directly engulfed by membrane. Piecemeal nucleus (PMN) occurs Saccharomyces cerevisiae at nucleus-vacuole (NV) junctions results pinching-off release vacuole nonessential portions nucleus. Previous studies concluded ATG genes are not absolutely required PMN. Here we...
AbstractAutophagy is a rapidly expanding field in the sense that our knowledge about molecular mechanism and its connections to wide range of physiological processes has increased substantially past decade. Similarly, vocabulary associated with autophagy grown concomitantly. This fact makes it difficult for readers, even those who work field, keep up ever-expanding terminology various autophagy-related processes. Accordingly, we have developed comprehensive glossary terms meant provide quick...
β-propellers that bind polyphosphoinositides (PROPPINs), a eukaryotic WD-40 motif-containing protein family, via their predicted β-propeller fold the PtdIns3P and PtdIns(3,5)P 2 using conserved FRRG motif. PROPPINs play key role in macroautophagy addition to other functions. We present 3.0-Å crystal structure of Kluyveromyces lactis Hsv2, which shares significant sequence homologies with its three Saccharomyces cerevisiae homologs Atg18, Atg21, Hsv2. It adopts seven-bladed rare nonvelcro...
Glucose-dependent regulation of carbon metabolism is a subject intensive studies. We have previously shown that the switch from gluconeogenesis to glycolysis associated with ubiquitin-proteasome linked elimination key enzyme fructose-1,6-bisphosphatase. Seven glucose induced degradation deficient (Gid)-proteins found in genomic screen were form complex binds FBPase. One subunits, Gid2/Rmd5, contains degenerated RING finger domain. In an vitro assay, heterologous expression GST-Gid2 leads...
The molecular details of the biogenesis double-membraned autophagosomes are poorly understood. We identify Saccharomyces cerevisiae AAA–adenosine triphosphatase Cdc48 and its substrate-recruiting cofactor Shp1/Ubx1 as novel components needed for autophagosome biogenesis. In mammals, homologue p97/VCP Shp1 p47 mediate Golgi reassembly by extracting an unknown monoubiquitinated fusion regulator from a complex. find no requirement ubiquitination or proteasome system but detect interaction with...
Metabolic adaptation of Saccharomyces cerevisiaecells from a nonfermentable carbon source to glucose induces selective, rapid breakdown the gluconeogenetic key enzyme fructose-1,6-bisphosphatase (FBPase), process called catabolite degradation. Herein, we identify eight novel GID genes required for proteasome-dependent degradation FBPase. Four yeast proteins contain CTLH domain unknown function. All them are Gid proteins. The site has been controversial until now. Two FBPase pathways have...
AbstractAtg18p and Atg21p are two highly homologous yeast autophagy proteins. Atg18p functions in both the selective Cvt-pathway, while function of is restricted to Cvt-pathway. The genome encodes with Ygr223cp (Hsv2p) a third member this protein family. So far no has been assigned Ygr223cp. By colocalization endosomal marker Snf7-RFP an RFP-tagged FYVE domain, we here identify localization pool Atg18p, at endosomes. Endosomal recruitment all three proteins depends on PtdIns3P generated by...
Perhaps the most complex step of macroautophagy is formation double-membrane autophagosome. The majority autophagy-related (Atg) proteins are thought to participate in nucleation and expansion phagophore, and/or completion this compartment. Monitoring part process difficult, typically involves electron microscopy analysis; however, unless three-dimensional tomography performed, even method cannot be used easily determine if phagophore completely enclosed. Accordingly, a complementary...
We here report the identification of AUT10 as a novel gene required for both cytoplasm to vacuole targeting proaminopeptidase I and starvation‐induced autophagy. aut10 Δ cells are impaired in maturation under starvation non‐starvation conditions. A lack Aut10p causes defect autophagy prior vacuolar uptake autophagosomes. Homozygous diploids do not sporulate. Vacuolar acidification indicated by accumulation quinacrine is normal mature proteinases present. biologically active Ha‐tagged Aut10p,...
Autophagocytosis is a starvation-induced process, carrying proteins destined for degradation to the lysosome. In yeast Saccharomyces cerevisiae, autophagic process visualized by appearance of vesicles in vacuoles proteinase yscB-deficient strains during starvation. aut3-1 mutant cells which exhibit block have been isolated previously. By using drastically reduced sporulation frequency homozygous diploid cells, AUT3 gene was cloned complementation. The Aut3 protein consists 897 amino acids....
Catabolite inactivation of fructose-1,6-bisphosphatase (FBPase), a key enzyme in gluconeogenesis, is due to phosphorylation and subsequent degradation the yeast Saccharomyces cerevisiae. The process had been shown depend on action proteasome. Here we report that components ubiquitin pathway target FBPase proteolysis. Upon glucose addition cells cultured nonfermentable carbon sources ubiquitinated vivo. A multiubiquitin chain containing isopeptide linkages at Lys48 attached FBPase. Formation...
Atg18 and Atg21 are homologous S. cerevisiae autophagy proteins. is essential for biogenesis of Cvt vesicles autophagosomes, while only vesicle formation. We found that mutated Atg18‐(FTTGT), which lost almost completely its binding to PtdIns3P PtdIns(3,5)P 2 , non‐functional during the pathway but active pexophagy. Since does not depend on we conclude requires PtdIns3P. Mutated Atg21‐(FTTGT) inactive showed partly reduced PtdIns‐phosphates, suggesting further lipid domains in Atg21....
Addition of glucose to cells the yeast<i>Saccharomyces cerevisiae</i> growing on a non-fermentable carbon source leads selective and rapid degradation fructose-1,6-bisphosphatase. This so called catabolite inactivation enzyme is brought about by ubiquitin-proteasome system. To identify additional components machinery, we isolated three mutant strains, <i>gid1</i>, <i>gid2</i>, <i>gid3</i>, defective in glucose-induced fructose-1,6-bisphospha-tase. All strains show addition defect other...
Autophagosomes and Cvt vesicles are limited by two membrane layers. The biogenesis of these unconventional the origin their membranes hardly understood. Here we identify in Saccharomyces cerevisiae Trs85, a nonessential component TRAPP complexes, to be required for vesicles. complexes function endoplasmic reticulum-to-Golgi Golgi trafficking. Growing trs85Δ cells show defect organization preautophagosomal structure. Although proaminopeptidase I is normally recruited structure, recruitment...
Rapid estimation of the macroautophagi crate has become great importance over past few years. A variety methods to follow autophagy were established both in S. cerevisiae and mammalian system. In yeast,measuring breakdown GFP-Atg8,and cells counting increase LC3 puncta, have most commonly used assays quantify autophagy. Here, we provide degradation Pgk1-GFP followed immunoblots as a new convenient tool nonselective bulk yeast.
Nucleophagy, the mechanism for autophagic degradation of nuclear material, occurs in both a macro- and micronucleophagic manner. Upon nitrogen deprivation, we observed, an in-depth fluorescence microscopy study, formation micronuclei: small parts superfluous components surrounded by perinuclear ER. We identified two types micronuclei associated with corresponding mode. Our results showed that macronucleophagy degraded these smaller micronuclei. Engulfed Atg8-positive phagophores containing...
The yeast PROPPIN Atg18 folds as a β-propeller with two binding sites for phosphatidylinositol-3-phosphate (PtdIns3P) and PtdIns(3,5)P2 at its circumference. Membrane insertion of an amphipathic loop leads to membrane tubulation fission. has known functions the PAS during macroautophagy, but functional relevance endosomal vacuolar pool is not well understood. Here we show in proximity-dependent labeling approach by co-immunoprecipitations that interacts Vps35, central component retromer...