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Publication Metadata only Advances in template-based protein docking by utilizing interfaces towards completing structural interactome(Current Biology Ltd, 2015) N/A; N/A; N/A; Department of Chemical and Biological Engineering; Department of Computer Engineering; Muratçıoğlu, Serena; Maiorov, Emine Güven; Keskin, Özlem; Gürsoy, Attila; PhD Student; PhD Student; Faculty Member; Faculty Member; Department of Chemical and Biological Engineering; Department of Computer Engineering; The Center for Computational Biology and Bioinformatics (CCBB); Graduate School of Sciences and Engineering; Graduate School of Sciences and Engineering; College of Engineering; College of Engineering; N/A; N/A; 26605; 8745The increase in the number of structurally determined protein complexes strengthens template-based docking (TBD) methods for modelling protein-protein interactions (PPIs). These methods utilize the known structures of protein complexes as templates to predict the quaternary structure of the target proteins. The templates may be partial or complete structures. Interface based (partial) methods have recently gained interest due in part to the observation that the interface regions are reusable. We describe how available template interfaces can be used to obtain the structural models of protein interactions. Despite the agreement that a majority of the protein complexes can be modelled using the available Protein Data Bank (PDB) structures, a handful of studies argue that we need more template proteins to increase the structural coverage of PPIs. We also discuss the performance of the interface TBD methods at large scale, and the significance of capturing multiple conformations for improving accuracy.Publication Open Access Androgen receptor-mediated transcription in prostate cancer(Multidisciplinary Digital Publishing Institute (MDPI), 2022) Morova, Tunç; Department of Computer Engineering; Department of Chemical and Biological Engineering; Lack, Nathan Alan; Özturan, Doğancan; Faculty Member; PhD Student; Department of Computer Engineering; Department of Chemical and Biological Engineering; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; 120842; N/AAndrogen receptor (AR)-mediated transcription is critical in almost all stages of prostate cancer (PCa) growth and differentiation. This process involves a complex interplay of coregulatory proteins, chromatin remodeling complexes, and other transcription factors that work with AR at cis-regulatory enhancer regions to induce the spatiotemporal transcription of target genes. This enhancer-driven mechanism is remarkably dynamic and undergoes significant alterations during PCa progression. In this review, we discuss the AR mechanism of action in PCa with a focus on how cis-regulatory elements modulate gene expression. We explore emerging evidence of genetic variants that can impact AR regulatory regions and alter gene transcription in PCa. Finally, we highlight several outstanding questions and discuss potential mechanisms of this critical transcription factor.Publication Metadata only Comparative biological network analysis for differentially expressed proteins as a function of bacilysin biosynthesis in Bacillus subtilis(2022) Kutnu, Meltem; İşlerel, Elif Tekin; Özcengiz, Gülay; Department of Chemical and Biological Engineering; Tunçbağ, Nurcan; Faculty Member; Department of Chemical and Biological Engineering; College of Engineering; 245513The Gram-positive bacterium Bacillus subtilis produces a diverse range of secondary metabolites with different structures and activities. Among them, bacilysin is an enzymatically synthesized dipeptide that consists of L-alanine and L-anticapsin. Previous research by our group has suggested bacilysin’s role as a pleiotropic molecule in its producer, B. subtilis PY79. However, the nature of protein interactions in the absence of bacilysin has not been defined. In the present work, we constructed a protein–protein interaction subnetwork by using Omics Integrator based on our recent comparative proteomics data obtained from a bacilysin-silenced strain, OGU1. Functional enrichment analyses on the resulting networks pointed to certain putatively perturbed pathways such as citrate cycle, quorum sensing and secondary metabolite biosynthesis. Various molecules, which were absent from the experimental data, were included in the final network. We believe that this study can guide further experiments in the identification and confirmation of protein–protein interactions in B. subtilis.Publication Metadata only Conservation of migratory species(Cell Press, 2018) Horns, Joshua J.; Department of Molecular Biology and Genetics; Şekercioğlu, Çağan Hakkı; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; 327589N/APublication Metadata only Covid-19 under spotlight: a close look at the origin, transmission, diagnosis, and treatment of the 2019-nCoV disease(Wiley, 2020) Sheervalilou, Roghayeh; Shirvaliloo, Milad; Dadashzadeh, Nahid; Shirvalilou, Sakine; Shahraki, Omolbanin; Pilehvar-Soltanahmadi, Younes; Ghaznavi, Habib; Khoei, Samideh; N/A; Nazarlou, Ziba; PhD Student; Graduate School of Sciences and Engineering; N/AMonths after the outbreak of a new flu-like disease in China, the entire world is now in a state of caution. The subsequent less-anticipated propagation of the novel coronavirus disease, formally known as COVID-19, not only made it to headlines by an overwhelmingly high transmission rate and fatality reports, but also raised an alarm for the medical community all around the globe. Since the causative agent, SARS-CoV-2, is a recently discovered species, there is no specific medicine for downright treatment of the infection. This has led to an unprecedented societal fear of the newly born disease, adding a psychological aspect to the physical manifestation of the virus. Herein, the COVID-19 structure, epidemiology, pathogenesis, etiology, diagnosis, and therapy have been reviewed.Publication Open Access Development, characterization, and hematopoietic differentiation of Griscelli syndrome type 2 induced pluripotent stem cells(BioMed Central, 2021) Güney-Esken, Gülen; Erol, Özgür Doğuş; Pervin, Burcu; Korkusuz, Petek; Günel-Özcan, Ayşen; Uçkan-Çetinkaya, Duygu; Aerts-Kaya, Fatima; Sevinç, Gülben Gürhan; Önder, Tamer Tevfik; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); Graduate School of Health Sciences; School of Medicine; N/A; 42946Background: Griscelli syndrome type 2 (GS-2) is a rare, autosomal recessive immune deficiency syndrome caused by a mutation in the RAB27A gene, which results in the absence of a protein involved in vesicle trafficking and consequent loss of function of in particular cytotoxic T and NK cells. Induced pluripotent stem cells (iPSC) express genes associated with pluripotency, have the capacity for infinite expansion, and can differentiate into cells from all three germ layers. They can be induced using integrative or non-integrative systems for transfer of the Oct4, Sox2, Klf4, and cMyc (OSKM) transcription factors. To better understand the pathophysiology of GS-2 and to test novel treatment options, there is a need for an in vitro model of GS-2. Methods: here, we generated iPSCs from 3 different GS-2 patients using lentiviral vectors. The iPSCs were characterized using flow cytometry and RT-PCR and tested for the expression of pluripotency markers. In vivo differentiation to cells from all three germlines was tested using a teratoma assay. In vitro differentiation of GS-2 iPSCs into hematopoietic stem and progenitor cells was done using Op9 feeder layers and specified media. Results: all GS-2 iPSC clones displayed a normal karyotype (46XX or 46XY) and were shown to express the same RAB27A gene mutation that was present in the original somatic donor cells. GS-2 iPSCs expressed SSEA1, SSEA4, TRA-1-60, TRA-1-81, and OCT4 proteins, and SOX2, NANOG, and OCT4 expression were confirmed by RT-PCR. Differentiation capacity into cells from all three germ layers was confirmed using the teratoma assay. GS-2 iPSCs showed the capacity to differentiate into cells of the hematopoietic lineage. Conclusions: using the lentiviral transfer of OSKM, we were able to generate different iPSC clones from 3 GS-2 patients. These cells can be used in future studies for the development of novel treatment options and to study the pathophysiology of GS-2 disease.Publication Metadata only Extracellular glucose level regulates dependence on 78 for cell surface localization of multipass transmembrane proteins in HeLa cells(Wiley, 2018) Toyoda, Yusuke; Sarov, Mihail; Saitoh, Shigeaki; Department of Molecular Biology and Genetics; Akarlar, Büşra; Other; Faculty Member; Department of Molecular Biology and Genetics; College of Sciences; N/A; 105301Publication Metadata only Genome-wide chromatin state transitions associated with developmental and environmental cues(CELL PRESS, 2013) Zhu, Jiang; Adli, Mazhar; Zou, James Y.; Verstappen, Griet; Coyne, Michael; Zhang, Xiaolan; Durham, Timothy; Miri, Mohammad; Deshpande, Vikram; De Jager, Philip L.; Bennett, David A.; Houmard, Joseph A.; Muoio, Deborah M.; Camahort, Ray; Cowan, Chad A.; Meissner, Alexander; Epstein, Charles B.; Shoresh, Noam; Bernstein, Bradley E.; N/A; Önder, Tamer Tevfik; Faculty Member; School of Medicine; 42946Differences in chromatin organization are key to the multiplicity of cell states that arise from a single genetic background, yet the landscapes of in vivo tissues remain largely uncharted. Here, we mapped chromatin genome-wide in a large and diverse collection of human tissues and stem cells. The maps yield unprecedented annotations of functional genomic elements and their regulation across developmental stages, lineages, and cellular environments. They also reveal global features of the epigenome, related to nuclear architecture, that also vary across cellular phenotypes. Specifically, developmental specification is accompanied by progressive chromatin restriction as the default state transitions from dynamic remodeling to generalized compaction. Exposure to serum in vitro triggers a distinct transition that involves de novo establishment of domains with features of constitutive heterochromatin. We describe how these global chromatin state transitions relate to chromosome and nuclear architecture, and discuss their implications for lineage fidelity, cellular senescence, and reprogramming.Publication Metadata only In-depth review: is hepcidin a marker for the heart and the kidney?(Springer, 2021) Afsar, Rengin Elsurer; Ibis, Avsin; Afsar, Baris; N/A; Kanbay, Mehmet; Faculty Member; School of Medicine; 110580Iron is an essential trace element involved in oxidation-reduction reactions, oxygen transport and storage, and energy metabolism. Iron in excess can be toxic for cells, since iron produces reactive oxygen species and is important for survival of pathogenic microbes. There is a fine-tuning in the regulation of serum iron levels, determined by intestinal absorption, macrophage iron recycling, and mobilization of hepatocyte stores versus iron utilization, primarily by erythroid cells in the bone marrow. Hepcidin is the major regulatory hormone of systemic iron homeostasis and is upregulated during inflammation. Hepcidin metabolism is altered in chronic kidney disease. Ferroportin is an iron export protein and mediates iron release into the circulation from duodenal enterocytes, splenic reticuloendothelial macrophages, and hepatocytes. Systemic iron homeostasis is controlled by the hepcidin-ferroportin axis at the sites of iron entry into the circulation. Hepcidin binds to ferroportin, induces its internalization and intracellular degradation, and thus inhibits iron absorption from enterocytes, and iron release from macrophages and hepatocytes. Recent data suggest that hepcidin, by slowing or preventing the mobilization of iron from macrophages, may promote atherosclerosis and may be associated with increased cardiovascular disease risk. This article reviews the current data regarding the molecular and cellular pathways of systemic and autocrine hepcidin production and seeks the answer to the question whether changes in hepcidin translate into clinical outcomes of all-cause and cardiovascular mortality, and cardiovascular and renal end-points.Publication Open Access Intraductal tubulopapillary neoplasm (ITPN) of the pancreas: a distinct entity among pancreatic tumors(Wiley, 2022) Paolino, G.; Esposito, I.; Hong, S.-M.; Baştürk, O.; Mattiolo, P.; Kaneko, T.; Veronese, N.; Scarpa, A.; Luchini, C.; Adsay, Nazmi Volkan; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; Koç University Hospital; 286248Aims: intraductal tubulopapillary neoplasm (ITPN)of the pancreas is a recently recognized pancreatictumor entity. Here we aimed to determine the mostimportant features with a systematic review coupledwith an integrated statistical approach.Methods and results: PubMed, SCOPUS, and Embasewere searched for studies reporting data on pancreaticITPN. The clinicopathological, immunohistochemical,and molecular data were summarized. Then a compre-hensive survival analysis and a comparative analysis ofthe molecular alterations of ITPN with those of pancre-atic ductal adenocarcinoma (PDAC) and intraductalpapillary mucinous neoplasm (IPMN) from referencecohorts (including the International Cancer GenomeConsortium- ICGC dataset and The Cancer GenomeAtlas, TCGA program) were conducted. The core find-ings of 128 patients were as follows: (i) Clinicopathologi-cal parameters: pancreatic head is the most commonsite; presence of an associated adenocarcinoma wasreported in 60% of cases, but with rare nodal metastasis.(ii) Immunohistochemistry: MUC1 (>90%) and MUC6(70%) were the most frequently expressed mucins. ITPNlacked the intestinal marker MUC2; unlike IPMN, it didnot express MUC5AC. (iii) Molecular landscape: Com-pared with PDAC/IPMN, the classic pancreatic driversKRAS,TP53,CDKN2A,SMAD4,GNAS,andRNF43were less altered in ITPN (P<0.001), whereasMCLamplifications,FGFR2fusions, andPI3KCAmutationswere commonly altered (P<0.001). (iv) Survival anal-ysis: ITPN with a “pure” branch duct involvementshowed the lowest risk of recurrence.Conclusion: ITPN is a distinct pancreatic neoplasmwith specific clinicopathological and molecular char-acteristics. Its recognition is fundamental for its clini-cal/prognostic implications and for the enrichment ofpotential targets for precision oncology.