Genos Ltd

Zagreb, Croatia

Genos Ltd

Zagreb, Croatia
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Genos Corporation and Shambrowest Corporation | Date: 2012-12-11

Remote control devices for computers, internet-enabled televisions, smart mobile phones, game consoles, disc players, home theater systems, audio systems, and set-top-boxes, and instruction manuals for use therewith sold as a unit; keyboards and instruction manuals for use therewith sold as a unit.

Bakovic M.P.,Genos Ltd. | Selman M.H.J.,Leiden University | Hoffmann M.,Leiden University | Hoffmann M.,Max Planck Institute for Dynamics of Complex Technical Systems | And 6 more authors.
Journal of Proteome Research | Year: 2013

Age and sex dependence of subclass specific immunoglobulin G (IgG) Fc N-glycosylation was evaluated for 1709 individuals from two isolated human populations. IgGs were obtained from plasma by affinity purification using 96-well protein G monolithic plates and digested with trypsin. Fc N-glycopeptides were purified and analyzed by negative-mode MALDI-TOF-MS with 4-chloro-α-cyanocinnamic acid (Cl-CCA) matrix. Age-associated glycosylation changes were more pronounced in younger individuals (<57 years) than in older individuals (>57 years) and in females than in males. Galactosylation and sialylation decreased with increasing age and showed significant sex dependence. Interestingly, the most prominent drop in the levels of galactosylated and sialylated glycoforms in females was observed around the age of 45 to 60 years when females usually enter menopause. The incidence of bisecting N-acetylglucosamine increased in younger individuals and reached a plateau at older age. Furthermore, we compared the results to the total IgG N-glycosylation of the same populations recently analyzed by hydrophilic interaction liquid chromatography (HILIC). Significant differences were observed in the levels of galactosylation, bisecting N-acetylglucosamine and particularly sialylation, which were shown to be higher in HILIC analysis. Age and sex association of glycosylation features was, to a large extent, comparable between MALDI-TOF-MS and HILIC IgG glycosylation profiling. © 2013 American Chemical Society.

Lauc G.,University of Zagreb | Lauc G.,Genos Ltd. | Rudan I.,Gen Information Ltd. | Rudan I.,University of Split | And 3 more authors.
Molecular BioSystems | Year: 2010

One hundred years have passed since Archibald Garrod postulated the one gene/one enzyme hypothesis. Since then, science has made significant progress and geneticists are now tackling an overwhelming complexity of gene regulation networks that underlie the genetics of complex human diseases. A particularly complex element in the biology of higher organisms is the genetics of protein glycosylation. Nearly all proteins that appeared after the emergence of multicellular life are glycosylated, but instead of being molded by a single gene, glycan structures are encoded within a network of several hundred glycosyltransferases, glycosidases, transporters, transcription factors and other proteins. In addition, in contrast to the linear structures of DNA and proteins, glycans have multiple branches that make their analysis significantly more challenging. However, recent developments in high throughput HPLC analysis have advanced glycan analysis significantly and it is now possible to address questions about the complex genetics of protein glycosylation. In this review we present some preliminary insights into this fascinating field. © 2010 The Royal Society of Chemistry.

Lauc G.,Genos Ltd | Lauc G.,University of Zagreb | Zoldo V.,University of Zagreb
Molecular BioSystems | Year: 2010

The majority of molecular processes in higher organisms are performed by various proteins and are thus determined by genes that encode these proteins. However, a significant structural component of at least half of all cellular proteins is not a polypeptide encoded by a single gene, but an oligosaccharide (glycan) synthesized by a network of proteins, resulting from the expression of hundreds of different genes. Relationships between hundreds of individual proteins that participate in glycan biosynthesis are very complex which enables the influence of environmental factors on the final structure of glycans, either by direct effects on individual enzymatic processes, or by induction of epigenetic changes that modify gene expression patterns. Until recently, the complexity of glycan structures prevented large scale studies of protein glycosylation, but recent advances in both glycan analysis and genotyping technologies, enabled the first insights into the intricate field of complex genetics of protein glycosylation. Mutations which inactivate genes involved in the synthesis of common N-glycan precursors are embryonically lethal. However, mutations in genes involved in modifications of glycan antennas are common and apparently contribute largely to individual phenotypic variations that exist in humans and other higher organisms. Some of these variations can be recognized as specific glyco-phenotypes that might represent specific evolutionary advantages or disadvantages. They are however, amenable to environmental influences and are thus less pre-determined than classical Mendelian mutations. © 2010 The Royal Society of Chemistry.

Gornik O.,University of Zagreb | Pavic T.,Genos Ltd. | Lauc G.,University of Zagreb | Lauc G.,Genos Ltd.
Biochimica et Biophysica Acta - General Subjects | Year: 2012

Background: Nearly all membrane and secreted proteins, as well as numerous intracellular proteins are glycosylated. However, contrary to proteins which are defined by their individual genetic templates, glycans are encoded in a complex dynamic network of hundreds of genes which participate in the complex biosynthetic pathway of protein glycosylation. Scope of review: This review summarizes present knowledge about the importance of alternative glycosylation of IgG and other proteins. Major conclusions: Numerous proteins depend on correct glycosylation for proper function. Very good example for this is the alternative glycosylation of IgG whose effector functions can be completely changed by the addition or removal of a single monosaccharide residue from its glycans. General significance: The change in the structure of a protein requires mutations in DNA and subsequent selection in the next generation, while even slight alterations in activity or intracellular localization of one or more biosynthetic enzymes are sufficient for the creation of novel glycan structures, which can then perform new functions. Glycome composition varies significantly between individuals, which makes them slightly or even significantly different in their ability to execute specific molecular pathways with numerous implications for development and progression of various diseases. This article is part of a Special Issue entitled Glycoproteomics. © 2011 Elsevier B.V. All rights reserved.

Horvat T.,University of Zagreb | Muzinic A.,Genos Ltd. | Barisic D.,University of Zagreb | Bosnar M.H.,Ruder Boskovic Institute | Zoldos V.,University of Zagreb
Biochimica et Biophysica Acta - General Subjects | Year: 2012

Background: Epigenetic changes play a role in all major events during tumorigenesis and changes in glycan structures are hallmarks of virtually every cancer. Also, proper N-glycosylation of membrane receptors is important in cell to cell and cell-environment communication. To study how modulation of epigenetic information can affect N-glycan expression we analyzed effects of epigenetic inhibitors on HeLa cell membrane N-glycome. Methods: HeLa cells were treated with DNA methylation (zebularin and 5-aza-2-deoxycytidine) and histone deacetylation (trichostatin A and Na-butyrate) inhibitors. The effects on HeLa cell membrane N-glycome were analyzed by hydrophilic interaction high performance liquid chromatography (HILIC). Results: Each of the four epigenetic inhibitors induced changes in the expression of HeLa cell membrane N-glycans that were seen either as an increase or a decrease of individual glycans in the total N-glycome. Compared to DNA methylation inhibitors, histone deacetylation inhibitors showed more moderate changes, probably due to their higher gene target selectivity. Conclusions: The results clearly show that composition of HeLa cell membrane N-glycome can be specifically altered by epigenetic inhibitors. General significance: Glycans on the cell membrane are essential elements of tumor cell's metastatic potential and are also an entry point for nearly all pathogenic microorganisms. Since epigenetic inhibitors used in this work are registered drugs, our results provide a new line of research in the application of these drugs as anticancer and antimicrobial agents. This article is part of a Special Issue entitled Glycoproteomics. © 2011 Elsevier B.V. All rights reserved.

ZoldoS V.,University of Zagreb | Horvat T.,University of Zagreb | Lauc G.,University of Zagreb | Lauc G.,Genos Ltd
Current Opinion in Chemical Biology | Year: 2013

Majority of eukaryotic proteins are glycosylated and their glycan moieties have numerous important structural, functional and regulatory roles. Because of structural complexity of glycans and technological limitations glycomics, and particularly glycoproteomics was not able to follow rapid progress in genomics and proteomics over last 30 years. However, the field of glycan has been progressing rapidly and first large-scale studies of the glycome have been completed recently. These studies have revealed significant differences in glycome composition between individuals, which may contribute to the human phenotypic variability. The current state-of-the-art in high-throughput glycomics and its integration with genomics, epigenomics and lipidomics is reviewed in this article. © 2012 Elsevier Ltd.

Zoldos V.,University of Zagreb | Novokmet M.,Genos Ltd | Beceheli I.,Genos Ltd | Lauc G.,Genos Ltd | Lauc G.,University of Zagreb
Glycoconjugate Journal | Year: 2013

The majority of all proteins are glycosylated and glycans have numerous important structural, functional and regulatory roles in various physiological processes. While structure of the polypeptide part of a glycoprotein is defined by the sequence of nucleotides in the corresponding gene, structure of a glycan part results from dynamic interactions between hundreds of genes, their protein products and environmental factors. The composition of the glycome attached to an individual protein, or to a complex mixture of proteins, like human plasma, is stable within an individual, but very variable between individuals. This variability stems from numerous common genetic polymorphisms reflecting in changes in the complex biosynthetic pathway of glycans, but also from the interaction with the environment. Environment can affect glycan biosynthesis at the level of substrate availability, regulation of enzyme activity and/or hormonal signals, but also through gene-environment interactions. Epigenetics provides a molecular basis how the environment can modify phenotype of an individual. The epigenetic information (DNA methylation pattern and histone code) is especially vulnerable to environmental effects in the early intrauterine and neo-natal development and many common late-onset diseases take root already at that time. The evidences showing the link between epigenetics and glycosylation are accumulating. Recent progress in high-throughput glycomics, genomics and epigenomics enabled first epidemiological and genome-wide association studies of the glycome, which are presented in this mini-review. © 2012 Springer Science+Business Media, LLC.

Over half of all proteins are glycosylated, and alterations in glycosylation have been observed in numerous physiological and pathological processes. Attached glycans significantly affect protein function; but, contrary to polypeptides, they are not directly encoded by genes, and the complex processes that regulate their assembly are poorly understood. A novel approach combining genome-wide association and high-throughput glycomics analysis of 2,705 individuals in three population cohorts showed that common variants in the Hepatocyte Nuclear Factor 1α (HNF1α) and fucosyltransferase genes FUT6 and FUT8 influence N-glycan levels in human plasma. We show that HNF1α and its downstream target HNF4α regulate the expression of key fucosyltransferase and fucose biosynthesis genes. Moreover, we show that HNF1α is both necessary and sufficient to drive the expression of these genes in hepatic cells. These results reveal a new role for HNF1α as a master transcriptional regulator of multiple stages in the fucosylation process. This mechanism has implications for the regulation of immunity, embryonic development, and protein folding, as well as for our understanding of the molecular mechanisms underlying cancer, coronary heart disease, and metabolic and inflammatory disorders.

All immunoglobulin G molecules carry N-glycans, which modulate their biological activity. Changes in N-glycosylation of IgG associate with various diseases and affect the activity of therapeutic antibodies and intravenous immunoglobulins. We have developed a novel 96-well protein G monolithic plate and used it to rapidly isolate IgG from plasma of 2298 individuals from three isolated human populations. N-glycans were released by PNGase F, labeled with 2-aminobenzamide and analyzed by hydrophilic interaction chromatography with fluorescence detection. The majority of the structural features of the IgG glycome were consistent with previous studies, but sialylation was somewhat higher than reported previously. Sialylation was particularly prominent in core fucosylated glycans containing two galactose residues and bisecting GlcNAc where median sialylation level was nearly 80%. Very high variability between individuals was observed, approximately three times higher than in the total plasma glycome. For example, neutral IgG glycans without core fucose varied between 1.3 and 19%, a difference that significantly affects the effector functions of natural antibodies, predisposing or protecting individuals from particular diseases. Heritability of IgG glycans was generally between 30 and 50%. The individual's age was associated with a significant decrease in galactose and increase of bisecting GlcNAc, whereas other functional elements of IgG glycosylation did not change much with age. Gender was not an important predictor for any IgG glycan. An important observation is that competition between glycosyltransferases, which occurs in vitro, did not appear to be relevant in vivo, indicating that the final glycan structures are not a simple result of competing enzymatic activities, but a carefully regulated outcome designed to meet the prevailing physiological needs.

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