scholarly journals Evolved, Selective Erasers of Distinct Lysine Acylations

2019 ◽  
Author(s):  
Martin Spinck ◽  
Maria Ecke ◽  
Raphael Gasper ◽  
Heinz Neumann

AbstractLysine acetylation, including related lysine modifications such as butyrylation and crotonylation, is a widespread post-translational modification with important roles in many important physiological processes. However, uncovering the regulatory mechanisms that govern the reverse process, deacylation, has been challenging to address, in great part because the small set of lysine deacetylases (KDACs) that remove the modifications are promiscuous in their substrate and acylation-type preference. This lack of selectivity hinders a broader understanding of how deacylation is regulated at the cellular level and how it is correlated with lysine deacylation-related diseases. To facilitate the dissection of KDACs with respect to substrate specificity and modification type, it would be beneficial to re-engineer KDACs to be selective towards a given substrate and/or modification. To dissect the differential contributions of various acylations to cell physiology, we developed a novel directed evolution approach to create selective KDAC variants that are up to 400-fold selective towards butyryl- over crotonyl-lysine substrates. Structural analyses of this non-promiscuous KDAC revealed unprecedented insights regarding the conformational changes mediating the gain in specificity. As a second case study to illustrate the power of this approach, we re-engineer the human SirT1 to increase its selectivity towards acetylated versus crotonylated substrates. These new enzymes, as well as the generic approach that we report here, will greatly facilitate the dissection of the differential roles of lysine acylation in cell physiology.Significance StatementAcetylation of lysine residues features numerous roles in diverse physiological processes and correlates with the manifestation of metabolic diseases, cancer and ageing. The already huge diversity of the acetylome is multiplied by variations in the types of acylation. This complexity is in stark contrast to the small set of lysine deacetylases (KDACs) present in human cells, anticipating a pronounced substrate promiscuity.We device a strategy to tackle this disarray by creating KDAC variants with increased selectivity towards particular types of lysine acylations using a novel selection system. The variants facilitate the dissection of the differential contributions of particular acylations to gene expression, development and disease. Our structural analyses shed light on the mechanism of substrate discrimination by Sirtuin-type KDACs.

2019 ◽  
Vol 23 (15) ◽  
pp. 1663-1670 ◽  
Author(s):  
Chunyan Ao ◽  
Shunshan Jin ◽  
Yuan Lin ◽  
Quan Zou

Protein methylation is an important and reversible post-translational modification that regulates many biological processes in cells. It occurs mainly on lysine and arginine residues and involves many important biological processes, including transcriptional activity, signal transduction, and the regulation of gene expression. Protein methylation and its regulatory enzymes are related to a variety of human diseases, so improved identification of methylation sites is useful for designing drugs for a variety of related diseases. In this review, we systematically summarize and analyze the tools used for the prediction of protein methylation sites on arginine and lysine residues over the last decade.


Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 244
Author(s):  
Seung Hee Eom ◽  
Tae Kyung Hyun

Histone deacetylases (HDACs) are known as erasers that remove acetyl groups from lysine residues in histones. Although plant HDACs play essential roles in physiological processes, including various stress responses, our knowledge concerning HDAC gene families and their evolutionary relationship remains limited. In Brassica rapa genome, we identified 20 HDAC genes, which are divided into three major groups: RPD3/HDA1, HD2, and SIR2 families. In addition, seven pairs of segmental duplicated paralogs and one pair of tandem duplicated paralogs were identified in the B. rapa HDAC (BraHDAC) family, indicating that segmental duplication is predominant for the expansion of the BraHDAC genes. The expression patterns of paralogous gene pairs suggest a divergence in the function of BraHDACs under various stress conditions. Furthermore, we suggested that BraHDA3 (homologous of Arabidopsis HDA14) encodes the functional HDAC enzyme, which can be inhibited by Class I/II HDAC inhibitor SAHA. As a first step toward understanding the epigenetic responses to environmental stresses in Chinese cabbage, our results provide a solid foundation for functional analysis of the BraHDAC family.


Encyclopedia ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 350-359
Author(s):  
Motomichi Fujita ◽  
Manabu Sasada ◽  
Takuya Iyoda ◽  
Satoshi Osada ◽  
Hiroaki Kodama ◽  
...  

Biofunctional peptide FNIII14, which is derived from the 14th fibronectin (FN) type III-like (FN-III) repeat of FN molecule, is capable of inhibiting cell adhesion to the extracellular matrix (ECM). This functional site is usually buried within the molecular structure of FN, but can be exposed by conformational changes and proteolytic cleavage. Peptide FNIII14 can induce a conformational change in β1-integrin from the active to the inactive form, causing functional inactivation. Based on this anti-adhesive activity, peptide FNIII14 exhibits therapeutic potential for several diseases such as metabolic diseases, organ fibrosis, and malignant tumors. Peptide FNIII14 blocks integrin-mediated signaling by a mechanism entirely distinct from that of conventional antagonisitic peptides, including Arg-Gly-Asp peptides that competitively inhibit the ECM binding of integrin.


2021 ◽  
Vol 22 (7) ◽  
pp. 3463
Author(s):  
Chia-Hung Lin ◽  
Chen-Chung Liao ◽  
Mei-Yu Chen ◽  
Teh-Ying Chou

Protein O-GlcNAcylation is a dynamic post-translational modification involving the attachment of N-acetylglucosamine (GlcNAc) to the hydroxyl groups of Ser/Thr residues on numerous nucleocytoplasmic proteins. Two enzymes are responsible for O-GlcNAc cycling on substrate proteins: O-GlcNAc transferase (OGT) catalyzes the addition while O-GlcNAcase (OGA) helps the removal of GlcNAc. O-GlcNAcylation modifies protein functions; therefore, dysregulation of O-GlcNAcylation affects cell physiology and contributes to pathogenesis. To maintain homeostasis of cellular O-GlcNAcylation, there exists feedback regulation of OGT and OGA expression responding to fluctuations of O-GlcNAc levels; yet, little is known about the molecular mechanisms involved. In this study, we investigated the O-GlcNAc-feedback regulation of OGT and OGA expression in lung cancer cells. Results suggest that, upon alterations in O-GlcNAcylation, the regulation of OGA expression occurs at the mRNA level and likely involves epigenetic mechanisms, while modulation of OGT expression is through translation control. Further analyses revealed that the eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) contributes to the downregulation of OGT induced by hyper-O-GlcNAcylation; the S5A/S6A O-GlcNAcylation-site mutant of 4E-BP1 cannot support this regulation, suggesting an important role of O-GlcNAcylation. The results provide additional insight into the molecular mechanisms through which cells may fine-tune intracellular O-GlcNAc levels to maintain homeostasis.


1995 ◽  
Vol 269 (3) ◽  
pp. C775-C784 ◽  
Author(s):  
K. D. Wu ◽  
W. S. Lee ◽  
J. Wey ◽  
D. Bungard ◽  
J. Lytton

The Ca(2+)-adenosinetriphosphatase pump of the sarcoplasmic or endoplasmic reticulum (SERCA) plays a critical role in Ca2+ signaling and homeostasis in all cells and is encoded by a family of homologous and alternatively spliced genes. To understand more clearly the role the different isoforms play in cell physiology, we have undertaken a quantitative and qualitative assessment of the tissue distribution of transcripts encoding each SERCA isoform. SERCA1 expression is restricted to fast-twitch striated muscles, SERCA2a to cardiac and slow-twitch striated muscles, whereas SERCA2b is ubiquitously expressed. SERCA3 is expressed most abundantly in large and small intestine, thymus, and cerebellum and at lower levels in spleen, lymph node, and lung. In situ hybridization analyses revealed SERCA3 transcripts in cells of the intestinal crypt, the thymic cortex, and Purkinje cells in cerebellum. In addition, SERCA3 was expressed abundantly in isolated rat spleen lymphocytes, in various murine lymphoid cell lines, and in primary cultured microvascular endothelial cells. This analysis demonstrates that SERCA3 is expressed selectively in cells in which Ca2+ signaling plays a critical and sensitive role in regulating physiological processes.


2020 ◽  
Vol 21 (22) ◽  
pp. 8746
Author(s):  
Julie Briot ◽  
Michel Simon ◽  
Marie-Claire Méchin

Deimination (or citrullination) is a post-translational modification catalyzed by a calcium-dependent enzyme family of five peptidylarginine deiminases (PADs). Deimination is involved in physiological processes (cell differentiation, embryogenesis, innate and adaptive immunity, etc.) and in autoimmune diseases (rheumatoid arthritis, multiple sclerosis and lupus), cancers and neurodegenerative diseases. Intermediate filaments (IF) and associated proteins (IFAP) are major substrates of PADs. Here, we focus on the effects of deimination on the polymerization and solubility properties of IF proteins and on the proteolysis and cross-linking of IFAP, to finally expose some features of interest and some limitations of citrullinomes.


1992 ◽  
Vol 285 (2) ◽  
pp. 419-425 ◽  
Author(s):  
U Christensen ◽  
L Mølgaard

The kinetics of a series of Glu-plasminogen ligand-binding processes were investigated at pH 7.8 and 25 degrees C (in 0.1 M-NaCl). The ligands include compounds analogous to C-terminal lysine residues and to normal lysine residues. Changes of the Glu-plasminogen protein fluorescence were measured in a stopped-flow instrument as a function of time after rapid mixing of Glu-plasminogen and ligand at various concentrations. Large positive fluorescence changes (approximately 10%) accompany the ligand-induced conformational changes of Glu-plasminogen resulting from binding at weak lysine-binding sites. Detailed studies of the concentration-dependencies of the equilibrium signals and the rate constants of the process induced by various ligands showed the conformational change to involve two sites in a concerted positive co-operative process with three steps: (i) binding of a ligand at a very weak lysine-binding site that preferentially, but not exclusively, binds C-terminal-type lysine ligands, (ii) the rate-determining actual-conformational-change step and (iii) binding of one more lysine ligand at a second weak lysine-binding site that then binds the ligand more tightly. Further, totally independent initial small negative fluorescence changes (approximately 2-4%) corresponding to binding at the strong lysine-binding site of kringle 1 [Sottrup-Jensen, Claeys, Zajdel, Petersen & Magnusson (1978) Prog. Chem. Fibrinolysis Thrombolysis 3, 191-209] were observed for the C-terminal-type ligands. The finding that the conformational change in Glu-plasminogen involves two weak lysine-binding sites indicates that the effect cannot be assigned to any single kringle and that the problem of whether kringle 4 or kringle 5 is responsible for the process resolves itself. Probably kringle 4 and 5 are both participating. The involvement of two lysine binding-sites further makes the high specificity of Glu-plasminogen effectors more conceivable.


Micromachines ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 562 ◽  
Author(s):  
Maria Savoca ◽  
Elisa Tonoli ◽  
Adeola Atobatele ◽  
Elisabetta Verderio

The biocatalytic activity of transglutaminases (TGs) leads to the synthesis of new covalent isopeptide bonds (crosslinks) between peptide-bound glutamine and lysine residues, but also the transamidation of primary amines to glutamine residues, which ultimately can result into protein polymerisation. Operating with a cysteine/histidine/aspartic acid (Cys/His/Asp) catalytic triad, TGs induce the post-translational modification of proteins at both physiological and pathological conditions (e.g., accumulation of matrices in tissue fibrosis). Because of the disparate biotechnological applications, this large family of protein-remodelling enzymes have stimulated an escalation of interest. In the past 50 years, both mammalian and microbial TGs polymerising activity has been exploited in the food industry for the improvement of aliments’ quality, texture, and nutritive value, other than to enhance the food appearance and increased marketability. At the same time, the ability of TGs to crosslink extracellular matrix proteins, like collagen, as well as synthetic biopolymers, has led to multiple applications in biomedicine, such as the production of biocompatible scaffolds and hydrogels for tissue engineering and drug delivery, or DNA-protein bio-conjugation and antibody functionalisation. Here, we summarise the most recent advances in the field, focusing on the utilisation of TGs-mediated protein multimerisation in biotechnological and bioengineering applications.


Diagnostics ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1836
Author(s):  
Dmitry Tikhonov ◽  
Liudmila Kulikova ◽  
Vladimir Rudnev ◽  
Arthur T. Kopylov ◽  
Amir Taldaev ◽  
...  

Post-translational modification (PTM) leads to conformational changes in protein structure, modulates the biological function of proteins, and, consequently, changes the signature of metabolic transformations and the immune response in the body. Common PTMs are reversible and serve as a mechanism for modulating metabolic trans-formations in cells. It is likely that dysregulation of post-translational cellular signaling leads to abnormal proliferation and oncogenesis. We examined protein PTMs in the blood samples from patients with kidney cancer. Conformational changes in proteins after modification were analyzed. The proteins were analyzed using ultra-high resolution HPLC-MS/MS and structural analysis was performed with the AMBER and GROMACS software packages. Fifteen proteins containing PTMs were identified in blood samples from patients with kidney cancer. For proteins with PDB structures, a comparative analysis of the structural changes accompanying the modifications was performed. Results revealed that PTMs are localized in stable and compact space protein globule motifs that are exposed to a solvent. The phenomenon of modification is accompanied, as a rule, by an increase in the area available for the solvent of the modified amino acid residue and its active environment.


2021 ◽  
Vol 134 (11) ◽  
Author(s):  
Shu-Heng Jiang ◽  
Ya-Hui Wang ◽  
Li-Peng Hu ◽  
Xu Wang ◽  
Jun Li ◽  
...  

ABSTRACT The classical neurotransmitter serotonin or 5-hydroxytryptamine (5-HT), synthesized from tryptophan, can be produced both centrally and peripherally. Through binding to functionally distinct receptors, serotonin is profoundly implicated in a number of fundamental physiological processes and pathogenic conditions. Recently, serotonin has been found covalently incorporated into proteins, a newly identified post-translational modification termed serotonylation. Transglutaminases (TGMs), especially TGM2, are responsible for catalyzing the transamidation reaction by transferring serotonin to the glutamine residues of target proteins. Small GTPases, extracellular matrix protein fibronectin, cytoskeletal proteins and histones are the most reported substrates for serotonylation, and their functions are triggered by this post-translational modification. This Review highlights the roles of serotonylation in physiology and diseases and provides perspectives for pharmacological interventions to ameliorate serotonylation for disease treatment.


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