A5083200637- Cellular transport and secretion
- Retinal Development and Disorders
- Microtubule and mitosis dynamics
- PI3K/AKT/mTOR signaling in cancer
- Calcium signaling and nucleotide metabolism
- Pancreatic function and diabetes
- Biochemical and Molecular Research
- Cell Adhesion Molecules Research
- Erythrocyte Function and Pathophysiology
- Caveolin-1 and cellular processes
- Ubiquitin and proteasome pathways
- NF-κB Signaling Pathways
- Adenosine and Purinergic Signaling
- Mass Spectrometry Techniques and Applications
- Polysaccharides and Plant Cell Walls
- Folate and B Vitamins Research
- Lung Cancer Treatments and Mutations
- Cancer-related Molecular Pathways
- Genomics and Phylogenetic Studies
- Histone Deacetylase Inhibitors Research
- Plant Reproductive Biology
- RNA and protein synthesis mechanisms
- RNA Interference and Gene Delivery
- Protein Degradation and Inhibitors
- Protein Kinase Regulation and GTPase Signaling
University of Ioannina
2012-2024
Shree Krishna Hospital
2021
Indian Institute of Technology Hyderabad
2021
Foundation for Research and Technology Hellas
2005-2019
FORTH Institute of Molecular Biology and Biotechnology
2012-2016
Institute of Molecular Biology and Biotechnology
2016
Max Planck Institute of Molecular Cell Biology and Genetics
1999-2004
Max Planck Society
2001
European Molecular Biology Laboratory
1999-2000
European Molecular Biology Organization
1998
Generation and turnover of phosphoinositides (PIs) must be coordinated in a spatial- temporal-restricted manner. The small GTPase Rab5 interacts with two PI 3-kinases, Vps34 PI3Kβ, suggesting that it regulates the production 3-PIs at various stages early endocytic pathway. Here, we discovered also directly 5- 4-phosphatases stimulates their activity. phosphatidylinositol 3-phosphate (PtdIns[3]P) through dual mechanism, by phosphorylating via hierarchical enzymatic cascade...
Rab5 regulates endocytic membrane traffic by specifically recruiting cytosolic effector proteins to their site of action on early endosomal membranes. We have characterized a new complex involved in fusion events. This includes novel protein, Rabenosyn-5, which, like the previously endosome antigen 1 (EEA1), contains an FYVE finger domain and is recruited phosphatidylinositol-3-kinase–dependent fashion endosomes. Rabenosyn-5 complexed Sec1-like protein hVPS45. hVPS45 does not interact...
The small GTPase Rab5 is a key regulator of clathrin-mediated endocytosis. On early endosomes, within spatially restricted domain enriched in phosphatydilinositol-3-phosphate [PI(3)P], coordinates complex network effectors that functionally cooperate membrane tethering, fusion, and organelle motility. Here we discovered novel PI(3)P-binding effector, Rabankyrin-5, which localises to endosomes stimulates their fusion activity. In addition however, Rabankyrin-5 large vacuolar structures...
ABSTRACT Endocytosis plays a crucial role in receptor signalling. VEGFR2 (also known as KDR) and its ligand VEGFA are fundamental neovascularisation. However, our understanding of the endocytosis signalling remains limited. Despite existence diverse internalisation routes, only endocytic pathway for is clathrin-mediated pathway. Here, we show that this predominant route absence ligand. Intriguingly, induces new itinerary VEGFR2, macropinocytosis, which becomes prevalent presence ligand,...
Localized translation is vital to polarized cells and requires precise robust distribution of different mRNAs ribosomes across the cell. However, underlying molecular mechanisms are poorly understood important players lacking. Here, we discovered a Rab5 effector, five-subunit endosomal RNA/ribosome intermediary (FERRY) complex, that recruits early endosomes through direct mRNA-interaction. FERRY displays preferential binding certain groups transcripts, including encoding mitochondrial...
The PIK3CA gene is one of the most frequently mutated oncogenes in human cancers. It encodes p110α, catalytic subunit phosphatidylinositol 3-kinase alpha (PI3Kα), which activates signaling cascades leading to cell proliferation, survival, and growth. frequent mutation H1047R, results enzymatic overactivation. Understanding how H1047R causes enhanced activity protein atomic detail central developing mutant-specific therapeutics for cancer. To this end, Surface Plasmon Resonance (SPR)...
Weibel-Palade bodies (WPBs) are endothelial-specific organelles, which, upon fusion with the plasma membrane, release cargo molecules that essential in critical blood vessel functions such as thrombosis, inflammation and angiogenesis. Despite importance of WPBs, basic mechanisms mediate their secretion only poorly understood. Rab GTPases play fundamental role trafficking intracellular organelles. Yet, known WPB-associated Rabs Rab27a Rab3d. Here, to determine full spectrum WPB-Rabs we...
Filamentous fungi provide excellent systems for investigating the role of AP-2 complex in polar growth. Using Aspergillus nidulans, we show that has a clathrin-independent essential polarity maintenance and This is line with sequence analysis showing β subunit (β2) higher lacks clathrin-binding domain, experiments does not co-localize clathrin. We genetic cellular evidence interacts endocytic markers SlaBEnd4 SagAEnd3 lipid flippases DnfA DnfB sub-apical collar region hyphae. The proper...
CD39 (ecto-nucleoside triphosphate diphosphohydrolase-1; E-NTPDase1) is a plasma membrane ecto-enzyme that regulates purinergic receptor signaling by controlling the levels of extracellular nucleotides. In blood vessels this enzyme exhibits thromboregulatory role through control platelet aggregation. localized in caveolae, which are invaginations with distinct lipid composition, similar to dynamic microdomains, called rafts. Cholesterol enriched together sphingolipids both rafts and as well...
ATP diphosphohydrolase activity (ATP‐DPH) has been previously identified in the paniculate fraction of human term placenta [Papamarcaki, T. & Tsolas, O. (1990) Mol. Cell. Biochem. 97 , 1–8]. In present study we have purified to homogeneity and characterized this activity. A 260‐fold purification obtained by solubilization particulate subsequent chromatography on DEAE Sepharose CL‐6B 5′‐AMP 4B. The preparation shown be free alkaline phosphatase even though placental extract is rich enzyme...
Abstract VEGFR2 is a critical angiogenic receptor playing key role in vascular homeostasis. Upon activation by VEGF, becomes endocytosed. Internalisation of facilitated, part, through clathrin mediated endocytosis (CME), the which function debated. Here, we confirm contribution CME uptake. However, curiously, find that different approaches inhibition exert contradictory effects on VEGF signalling; knockdown clathrin, or dynamin, overexpression dynamin K44A, do not affect VEGF-induced...
Prothymosin alpha (ProTalpha) is a histone H1-binding protein that interacts with the transcription coactivator CREB-binding and potentiates transcription. Based on coimmunoprecipitation mammalian two-hybrid assays, we show here ProTalpha forms complex oncoprotein SET. efficiently decondenses human sperm chromatin, while overexpression of GFP-ProTalpha in cells results global chromatin decondensation. These indicate decondensation compacted fibers an important step mechanism function.
Allosteric modulators offer a novel approach for kinase inhibition because they target less conserved binding sites compared to the active site; thus, higher selectivity may be obtained. PIK-108, known pan phosphoinositide 3-kinase (PI3K) inhibitor, was recently detected occupy non-ATP site in PI3Kα C-lobe. This newly identified pocket is located close residue 1047, which frequently mutated human cancers (H1047R). In order assess interactions, stability, and any possible allosteric effects...
Despite the progress in genomic DNA sequencing de novo of peptides is still required a biological research environment since many experiments are done organisms whose genomes not sequenced. A way to unambiguously retrieve peptide sequence from tandem mass spectrum assign correct ion type fragments. Here we describe method which improves specificity y-ion assignment throughout spectrum. The differential scanning technique requires that partially 18O labelled at their C-terminus and two...