Synergistic sequence contributions bias glycation outcomes

AbstractThe methylglyoxal-derived hydroimidazolone isomer, MGH-1, is an abundant advanced glycation end-product (AGE) associated with disease and age-related disorders. As AGE formation occurs spontaneously and without an enzyme, it remains unknown why certain sites on distinct proteins become modified with specific AGEs. Here, we use a combinatorial peptide library to determine the chemical features that favor MGH-1. When properly positioned, tyrosine is found to play an active mechanistic role that facilitates MGH-1 formation. This work offers mechanistic insight connecting multiple AGEs, including MGH-1 and carboxyethylarginine (CEA), and reconciles the role of negative charge in influencing glycation outcomes. Further, this study provides clear evidence that glycation outcomes can be influenced through long- or medium-range cooperative interactions. This work demonstrates that these chemical features also predictably template selective glycation on full-length protein targets expressed in mammalian cells. This information is vital for developing methods that control glycation in living cells and will enable the study of glycation as a functional post-translational modification.

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Pathogenesis of Age-related Cataract: a systematic review of proteomic studies

Current Proteomics ◽

10.2174/1570164617999201020205100 ◽

2020 ◽

Vol 17 ◽

Author(s):

Christina Karakosta ◽

Argyrios Tzamalis ◽

Michalis Aivaliotis ◽

Ioannis Tsinopoulos

Keyword(s):

Systematic Review ◽

Oxidant Stress ◽

Critical Role ◽

Human Lens ◽

Nuclear Cataract ◽

Cataract Formation ◽

Post Translational Modification ◽

Ability To Act ◽

Age Related

Background/Objective:: The aim of this systematic review is to identify all the available data on human lens proteomics with a critical role to age-related cataract formation in order to elucidate the physiopathology of the aging lens. Materials and Methods:: We searched on Medline and Cochrane databases. The search generated 328 manuscripts. We included nine original proteomic studies that investigated human cataractous lenses. Results:: Deamidation was the major age-related post-translational modification. There was a significant increase in the amount of αA-crystallin D-isoAsp58 present at all ages, while an increase in the extent of Trp oxidation was apparent in cataract lenses when compared to aged normal lenses. During aging, enzymes with oxidized cysteine at critical sites included GAPDH, glutathione synthase, aldehyde dehydrogenase, sorbitol dehydrogenase, and PARK7. Conclusion:: D-isoAsp in αA crystallin could be associated with the development of age-related cataract in human, by contributing to the denaturation of a crystallin, and decreasing its ability to act as a chaperone. Oxidation of Trp may be associated with nuclear cataract formation in human, while the role of oxidant stress in age-related cataract formation is dominant.

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Role of Protein Glycosylation in Interactions of Medically Relevant Fungi with the Host

Journal of Fungi ◽

10.3390/jof7100875 ◽

2021 ◽

Vol 7 (10) ◽

pp. 875

Author(s):

Manuela Gómez-Gaviria ◽

Ana P. Vargas-Macías ◽

Laura C. García-Carnero ◽

Iván Martínez-Duncker ◽

Héctor M. Mora-Montes

Keyword(s):

Protein Trafficking ◽

Mammalian Cells ◽

Fungal Infections ◽

Fungal Species ◽

Protein Glycosylation ◽

Amino Acid Side Chain ◽

Post Translational Modification ◽

Fungal Cell ◽

The Relationship

Protein glycosylation is a highly conserved post-translational modification among organisms. It plays fundamental roles in many biological processes, ranging from protein trafficking and cell adhesion to host–pathogen interactions. According to the amino acid side chain atoms to which glycans are linked, protein glycosylation can be divided into two major categories: N-glycosylation and O-glycosylation. However, there are other types of modifications such as the addition of GPI to the C-terminal end of the protein. Besides the importance of glycoproteins in biological functions, they are a major component of the fungal cell wall and plasma membrane and contribute to pathogenicity, virulence, and recognition by the host immunity. Given that this structure is absent in host mammalian cells, it stands as an attractive target for developing selective compounds for the treatment of fungal infections. This review focuses on describing the relationship between protein glycosylation and the host–immune interaction in medically relevant fungal species.

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Hydrogen Sulfide Biochemistry and Interplay with Other Gaseous Mediators in Mammalian Physiology

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/6290931 ◽

2018 ◽

Vol 2018 ◽

pp. 1-31 ◽

Cited By ~ 36

Author(s):

Alessandro Giuffrè ◽

João B. Vicente

Keyword(s):

Hydrogen Sulfide ◽

Mammalian Cells ◽

Protein Targets ◽

Metal Centers ◽

Cellular Processes ◽

Signaling Function ◽

Enzymatic Systems ◽

Bona Fide ◽

Different Levels

Hydrogen sulfide (H2S) has emerged as a relevant signaling molecule in physiology, taking its seat as a bona fide gasotransmitter akin to nitric oxide (NO) and carbon monoxide (CO). After being merely regarded as a toxic poisonous molecule, it is now recognized that mammalian cells are equipped with sophisticated enzymatic systems for H2S production and breakdown. The signaling role of H2S is mainly related to its ability to modify different protein targets, particularly by promoting persulfidation of protein cysteine residues and by interacting with metal centers, mostly hemes. H2S has been shown to regulate a myriad of cellular processes with multiple physiological consequences. As such, dysfunctional H2S metabolism is increasingly implicated in different pathologies, from cardiovascular and neurodegenerative diseases to cancer. As a highly diffusible reactive species, the intra- and extracellular levels of H2S have to be kept under tight control and, accordingly, regulation of H2S metabolism occurs at different levels. Interestingly, even though H2S, NO, and CO have similar modes of action and parallel regulatory targets or precisely because of that, there is increasing evidence of a crosstalk between the three gasotransmitters. Herein are reviewed the biochemistry, metabolism, and signaling function of hydrogen sulfide, as well as its interplay with the other gasotransmitters, NO and CO.

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O-GlcNAc cycling and the regulation of nucleocytoplasmic dynamics

Biochemical Society Transactions ◽

10.1042/bst20160171 ◽

2017 ◽

Vol 45 (2) ◽

pp. 427-436 ◽

Cited By ~ 15

Author(s):

Moriah Eustice ◽

Michelle R. Bond ◽

John A. Hanover

Keyword(s):

Structural Integrity ◽

Complex Structure ◽

Nutrient Sensing ◽

Nuclear Pore ◽

Post Translational Modification ◽

Nucleocytoplasmic Trafficking ◽

Protein Targets ◽

Multifunctional Enzymes ◽

And Function

The dynamic carbohydrate post-translational modification (PTM) O-linked β-N-acetyl glucosamine (O-GlcNAc) is found on thousands of proteins throughout the nucleus and cytoplasm, and rivals phosphorylation in terms of the number of substrates and pathways influenced. O-GlcNAc is highly conserved and essential in most organisms, with disruption of O-GlcNAc cycling linked to diseases ranging from cancer to neurodegeneration. Nuclear pore proteins were the first identified O-GlcNAc-modified substrates, generating intense and ongoing interest in understanding the role of O-GlcNAc cycling in nuclear pore complex structure and function. Recent advances in detecting and altering O-GlcNAcylation levels have provided insights into many mechanisms by which O-GlcNAcylation influences the nucleocytoplasmic localization and stability of protein targets. The emerging view is that the multifunctional enzymes of O-GlcNAc cycling are critical nutrient-sensing components of a complex network of signaling cascades involving multiple PTMs. Furthermore, O-GlcNAc plays a role in maintaining the structural integrity of the nuclear pore and regulating its function as the gatekeeper of nucleocytoplasmic trafficking.

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Cataract in the human lens: a systematic review of proteomic studies

10.1101/19009035 ◽

2019 ◽

Author(s):

Christina Karakosta ◽

Argyrios Tzamalis ◽

Michalis Aivaliotis ◽

Ioannis Tsinopoulos

Keyword(s):

Systematic Review ◽

Oxidant Stress ◽

Critical Role ◽

Human Lens ◽

Cataract Formation ◽

Post Translational Modification ◽

Lens Crystallins ◽

Ability To Act ◽

Age Related

AbstractBackground/AimThe aim of this systematic review is to identify all the available data on human lens proteomics with a critical role to age-related cataract formation in order to elucidate the physiopathology of the aging lens.MethodsWe searched on Medline and Cochrane databases. The search generated 328 manuscripts. We included nine original proteomic studies that investigated human cataractous lenses.ResultsDeamidation was the major age-related post-translational modification. There was a significant increase in the amount of αA-crystallin D-isoAsp58 present at all ages, while an increase in the extent of Trp oxidation was apparent in cataract lenses when compared to aged normal lenses. During aging, enzymes with oxidized cysteine at critical sites included GAPDH, glutathione synthase, aldehyde dehydrogenase, sorbitol dehydrogenase, and PARK7.ConclusionD-isoAsp in αA crystallin could be associated with the development of age-related cataract in human, by contributing to the denaturation of a crystallin, and decreasing its ability to act as a chaperone. Oxidation of Trp may be associated with nuclear cataract formation in man, while the role of oxidant stress in age-related cataract formation is dominant.SynopsisThe oxidative stress and the post-translational modification of deamidation in lens crystallins seem to play a significant role in the formation of age-related cataract in human.

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Histone Variant H3.3 Mutations in Defining the Chromatin Function in Mammals

Cells ◽

10.3390/cells9122716 ◽

2020 ◽

Vol 9 (12) ◽

pp. 2716

Author(s):

Matteo Trovato ◽

Vibha Patil ◽

Maja Gehre ◽

Kyung Min Noh

Keyword(s):

Mammalian Cells ◽

Functional Role ◽

Histone Variant ◽

Model Organisms ◽

Post Translational Modification ◽

Mammalian Development ◽

Histone 3 ◽

Oncogenic Mutations ◽

Health And Disease

The systematic mutation of histone 3 (H3) genes in model organisms has proven to be a valuable tool to distinguish the functional role of histone residues. No system exists in mammalian cells to directly manipulate canonical histone H3 due to a large number of clustered and multi-loci histone genes. Over the years, oncogenic histone mutations in a subset of H3 have been identified in humans, and have advanced our understanding of the function of histone residues in health and disease. The oncogenic mutations are often found in one allele of the histone variant H3.3 genes, but they prompt severe changes in the epigenetic landscape of cells, and contribute to cancer development. Therefore, mutation approaches using H3.3 genes could be relevant to the determination of the functional role of histone residues in mammalian development without the replacement of canonical H3 genes. In this review, we describe the key findings from the H3 mutation studies in model organisms wherein the genetic replacement of canonical H3 is possible. We then turn our attention to H3.3 mutations in human cancers, and discuss H3.3 substitutions in the N-terminus, which were generated in order to explore the specific residue or associated post-translational modification.

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Proteostasis Dysfunction in Aged Mammalian Cells. The Stressful Role of Inflammation

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.658742 ◽

2021 ◽

Vol 8 ◽

Author(s):

Diego Ruano

Keyword(s):

Quality Control ◽

Control Systems ◽

Mammalian Cells ◽

Protein Quality ◽

Protein Quality Control ◽

Normal Aging ◽

Cellular Protein ◽

World Population ◽

Age Related

Aging is a biological and multifactorial process characterized by a progressive and irreversible deterioration of the physiological functions leading to a progressive increase in morbidity. In the next decades, the world population is expected to reach ten billion, and globally, elderly people over 80 are projected to triple in 2050. Consequently, it is also expected an increase in the incidence of age-related pathologies such as cancer, diabetes, or neurodegenerative disorders. Disturbance of cellular protein homeostasis (proteostasis) is a hallmark of normal aging that increases cell vulnerability and might be involved in the etiology of several age-related diseases. This review will focus on the molecular alterations occurring during normal aging in the most relevant protein quality control systems such as molecular chaperones, the UPS, and the ALS. Also, alterations in their functional cooperation will be analyzed. Finally, the role of inflammation, as a synergistic negative factor of the protein quality control systems during normal aging, will also be addressed. A better comprehension of the age-dependent modifications affecting the cellular proteostasis, as well as the knowledge of the mechanisms underlying these alterations, might be very helpful to identify relevant risk factors that could be responsible for or contribute to cell deterioration, a fundamental question still pending in biomedicine.

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Dicarbonyl derived post-translational modifications: chemistry bridging biology and aging-related disease

Essays in Biochemistry ◽

10.1042/ebc20190057 ◽

2020 ◽

Vol 64 (1) ◽

pp. 97-110

Author(s):

Christian Sibbersen ◽

Mogens Johannsen

Keyword(s):

Mass Spectrometry ◽

Future Research ◽

Amino Acid Residues ◽

Post Translational Modification ◽

Dicarbonyl Compounds ◽

Protein Targets ◽

Post Translational Modifications ◽

Reactive Protein ◽

Glycation End Products ◽

Direct Mass Spectrometry

Abstract In living systems, nucleophilic amino acid residues are prone to non-enzymatic post-translational modification by electrophiles. α-Dicarbonyl compounds are a special type of electrophiles that can react irreversibly with lysine, arginine, and cysteine residues via complex mechanisms to form post-translational modifications known as advanced glycation end-products (AGEs). Glyoxal, methylglyoxal, and 3-deoxyglucosone are the major endogenous dicarbonyls, with methylglyoxal being the most well-studied. There are several routes that lead to the formation of dicarbonyl compounds, most originating from glucose and glucose metabolism, such as the non-enzymatic decomposition of glycolytic intermediates and fructosyl amines. Although dicarbonyls are removed continuously mainly via the glyoxalase system, several conditions lead to an increase in dicarbonyl concentration and thereby AGE formation. AGEs have been implicated in diabetes and aging-related diseases, and for this reason the elucidation of their structure as well as protein targets is of great interest. Though the dicarbonyls and reactive protein side chains are of relatively simple nature, the structures of the adducts as well as their mechanism of formation are not that trivial. Furthermore, detection of sites of modification can be demanding and current best practices rely on either direct mass spectrometry or various methods of enrichment based on antibodies or click chemistry followed by mass spectrometry. Future research into the structure of these adducts and protein targets of dicarbonyl compounds may improve the understanding of how the mechanisms of diabetes and aging-related physiological damage occur.

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