1
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Zhang YW, Lin NP, Guo X, Szabo-Fresnais N, Ortoleva PJ, Chou DHC. Omniligase-1-Mediated Phage-Peptide Library Modification and Insulin Engineering. ACS Chem Biol 2024; 19:506-515. [PMID: 38266161 DOI: 10.1021/acschembio.3c00685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
Chemical and enzymatic modifications of peptide-displayed libraries have been successfully employed to expand the phage display library. However, the requirement of specific epitopes and scaffolds has limited the scope of protein engineering using phage display. In this study, we present a novel approach utilizing omniligase-1-mediated selective and specific ligation on the phage pIII protein, offering a high conversion rate and compatibility with commercially available phage libraries. We applied this method to perform high-throughput engineering of insulin analogues with randomized B chain C-terminal regions. Insulin analogues with different B chain C-terminal segments were selected and exhibited biological activity equivalent to that of human insulin. Molecular dynamics studies of insulin analogues revealed a novel interaction between the insulin B27 residue and insulin receptor L1 domain. In summary, our findings highlight the potential of omniligase-1-mediated phage display in the development and screening of disulfide-rich peptides and proteins. This approach holds promise for the creation of novel insulin analogues with enhanced therapeutic properties and exhibits potential for the development of other therapeutic compounds.
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Affiliation(s)
- Yi Wolf Zhang
- Department of Pediatrics, Division of Diabetes and Endocrinology, Stanford University, Palo Alto, California 94304, United States
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Nai-Pin Lin
- Department of Pediatrics, Division of Diabetes and Endocrinology, Stanford University, Palo Alto, California 94304, United States
| | - Xu Guo
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Nicolas Szabo-Fresnais
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Peter J Ortoleva
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Danny Hung-Chieh Chou
- Department of Pediatrics, Division of Diabetes and Endocrinology, Stanford University, Palo Alto, California 94304, United States
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2
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Zhang YW, Zheng N, Chou DHC. Serine-mediated hydrazone ligation displaying insulin-like peptides on M13 phage pIII. Org Biomol Chem 2023; 21:8902-8909. [PMID: 37905463 DOI: 10.1039/d3ob01487h] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Phage display has emerged as a tool for the discovery of therapeutic antibodies and proteins. However, the effective display and engineering of structurally complex proteins, such as insulin, pose significant challenges due to the sequence of insulin, which is composed of two peptide chains linked by three disulfide bonds. In this study, we developed a new approach for the display of insulin-like peptides on M13 phage pIII, employing N-terminal serine-mediated hydrazone ligation. The insulin-displaying phage retains the biological binding affinity of human insulin. To address the viability loss after ligation, we introduced a trypsin-cleavable spacer on pIII, enabling insulin-displayed phage library selection. This method offers a general pathway for the display of structurally complex proteins on pIII, enhancing the practicality of selecting chemically modified phage libraries and opening avenues for the engineering of new insulin analogs for the treatment of diabetes by using phage display.
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Affiliation(s)
- Yi Wolf Zhang
- Department of Pediatrics, Division of Diabetes and Endocrinology, Stanford University, Palo Alto, CA 94304, USA.
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - Nan Zheng
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - Danny Hung-Chieh Chou
- Department of Pediatrics, Division of Diabetes and Endocrinology, Stanford University, Palo Alto, CA 94304, USA.
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3
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Determinants of IGF-II influencing stability, receptor binding and activation. Sci Rep 2022; 12:4695. [PMID: 35304516 PMCID: PMC8933565 DOI: 10.1038/s41598-022-08467-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 02/28/2022] [Indexed: 11/28/2022] Open
Abstract
Insulin like growth factor II (IGF-II) is involved in metabolic and mitogenic signalling in mammalian cells and plays important roles in normal fetal development and postnatal growth. It is structurally similar to insulin and binds not only with high affinity to the type 1 insulin-like growth factor receptor (IGF-1R) but also to the insulin receptor isoform A (IR-A). As IGF-II expression is commonly upregulated in cancer and its signalling promotes cancer cell survival, an antagonist that blocks IGF-II action without perturbing insulin signalling would be invaluable. The high degree of structural homology between the IR and IGF-1R makes selectively targeting either receptor in the treatment of IGF-II-dependent cancers very challenging. However, there are sequence differences between insulin and IGF-II that convey receptor selectivity and influence binding affinity and signalling outcome. Insulin residue YB16 is a key residue involved in maintaining insulin stability, dimer formation and IR binding. Mutation of this residue to glutamine (as found in IGF-II) results in reduced binding affinity. In this study we sought to determine if the equivalent residue Q18 in IGF-II plays a similar role. We show through site-directed mutagenesis of Q18 that this residue contributes to IGF-II structural integrity, selectivity of IGF-1R/IR binding, but surprisingly does not influence IR-A signalling activation. These findings provide insights into a unique IGF-II residue that can influence receptor binding specificity whilst having little influence on signalling outcome.
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4
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Páníková T, Mitrová K, Halamová T, Mrzílková K, Pícha J, Chrudinová M, Kurochka A, Selicharová I, Žáková L, Jiráček J. Insulin Analogues with Altered Insulin Receptor Isoform Binding Specificities and Enhanced Aggregation Stabilities. J Med Chem 2021; 64:14848-14859. [PMID: 34591477 DOI: 10.1021/acs.jmedchem.1c01388] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Insulin is a lifesaver for millions of diabetic patients. There is a need for new insulin analogues with more physiological profiles and analogues that will be thermally more stable than human insulin. Here, we describe the chemical engineering of 48 insulin analogues that were designed to have changed binding specificities toward isoforms A and B of the insulin receptor (IR-A and IR-B). We systematically modified insulin at the C-terminus of the B-chain, at the N-terminus of the A-chain, and at A14 and A18 positions. We discovered an insulin analogue that has Cα-carboxyamidated Glu at B31 and Ala at B29 and that has a more than 3-fold-enhanced binding specificity in favor of the "metabolic" IR-B isoform. The analogue is more resistant to the formation of insulin fibrils at 37 °C and is also more efficient in mice than human insulin. Therefore, [AlaB29,GluB31,amideB31]-insulin may be interesting for further clinical evaluation.
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Affiliation(s)
- Terezie Páníková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
- Department of Biochemistry and Microbiology, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague, Czech Republic
| | - Katarína Mitrová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
| | - Tereza Halamová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
| | - Karolína Mrzílková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
| | - Jan Pícha
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
| | - Martina Chrudinová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
| | - Andrii Kurochka
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
| | - Irena Selicharová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 116 10 Prague 6, Czech Republic
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5
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Jiráček J, Žáková L, Marek A. Radiolabeled hormones in insulin research, a minireview. J Labelled Comp Radiopharm 2020; 63:576-581. [PMID: 32909277 DOI: 10.1002/jlcr.3881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/23/2020] [Accepted: 08/30/2020] [Indexed: 11/05/2022]
Abstract
Preparation of both 125 I-labeled insulin and insulin-like growth factor 1 (IGF-1) was critical because it enabled a detailed characterization of binding properties of these important hormones towards their cognate transmembrane receptors. Binding modes of hundreds of hormone derivatives were analyzed using competition radioligand binding assays. This effort has resulted in development of six insulin analogs that are today clinically used for the treatment of diabetes. Here, we will briefly summarize a history of insulin research employing iodinated hormones.
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Affiliation(s)
- Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Aleš Marek
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
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6
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Potalitsyn P, Selicharová I, Sršeň K, Radosavljević J, Marek A, Nováková K, Jiráček J, Žáková L. A radioligand binding assay for the insulin-like growth factor 2 receptor. PLoS One 2020; 15:e0238393. [PMID: 32877466 PMCID: PMC7467306 DOI: 10.1371/journal.pone.0238393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 08/14/2020] [Indexed: 01/04/2023] Open
Abstract
Insulin-like growth factors 2 and 1 (IGF2 and IGF1) and insulin are closely related hormones that are responsible for the regulation of metabolic homeostasis, development and growth of the organism. Physiological functions of insulin and IGF1 are relatively well-studied, but information about the role of IGF2 in the body is still sparse. Recent discoveries called attention to emerging functions of IGF2 in the brain, where it could be involved in processes of learning and memory consolidation. It was also proposed that these functions could be mediated by the receptor for IGF2 (IGF2R). Nevertheless, little is known about the mechanism of signal transduction through this receptor. Here we produced His-tagged domain 11 (D11), an IGF2-binding element of IGF2R; we immobilized it on the solid support through a well-defined sandwich, consisting of neutravidin, biotin and synthetic anti-His-tag antibodies. Next, we prepared specifically radiolabeled [125I]-monoiodotyrosyl-Tyr2-IGF2 and optimized a sensitive and robust competitive radioligand binding assay for determination of the nanomolar binding affinities of hormones for D11 of IGF2. The assay will be helpful for the characterization of new IGF2 mutants to study the functions of IGF2R and the development of new compounds for the treatment of neurological disorders.
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Affiliation(s)
- Pavlo Potalitsyn
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University, Prague, Czech Republic
| | - Irena Selicharová
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Kryštof Sršeň
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Jelena Radosavljević
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Aleš Marek
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Kateřina Nováková
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Prague, Czech Republic
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7
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Chrudinová M, Žáková L, Marek A, Socha O, Buděšínský M, Hubálek M, Pícha J, Macháčková K, Jiráček J, Selicharová I. A versatile insulin analog with high potency for both insulin and insulin-like growth factor 1 receptors: Structural implications for receptor binding. J Biol Chem 2018; 293:16818-16829. [PMID: 30213860 PMCID: PMC6204900 DOI: 10.1074/jbc.ra118.004852] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 09/05/2018] [Indexed: 12/02/2022] Open
Abstract
Insulin and insulin-like growth factor 1 (IGF-1) are closely related hormones involved in the regulation of metabolism and growth. They elicit their functions through activation of tyrosine kinase–type receptors: insulin receptors (IR-A and IR-B) and IGF-1 receptor (IGF-1R). Despite similarity in primary and three-dimensional structures, insulin and IGF-1 bind the noncognate receptor with substantially reduced affinity. We prepared [d-HisB24, GlyB31, TyrB32]-insulin, which binds all three receptors with high affinity (251 or 338% binding affinity to IR-A respectively to IR-B relative to insulin and 12.4% binding affinity to IGF-1R relative to IGF-1). We prepared other modified insulins with the aim of explaining the versatility of [d-HisB24, GlyB31, TyrB32]-insulin. Through structural, activity, and kinetic studies of these insulin analogs, we concluded that the ability of [d-HisB24, GlyB31, TyrB32]-insulin to stimulate all three receptors is provided by structural changes caused by a reversed chirality at the B24 combined with the extension of the C terminus of the B chain by two extra residues. We assume that the structural changes allow the directing of the B chain C terminus to some extra interactions with the receptors. These unusual interactions lead to a decrease of dissociation rate from the IR and conversely enable easier association with IGF-1R. All of the structural changes were made at the hormones' Site 1, which is thought to interact with the Site 1 of the receptors. The results of the study suggest that merely modifications of Site 1 of the hormone are sufficient to change the receptor specificity of insulin.
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Affiliation(s)
- Martina Chrudinová
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Lenka Žáková
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Aleš Marek
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Ondřej Socha
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Miloš Buděšínský
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Martin Hubálek
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Jan Pícha
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Kateřina Macháčková
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Jiří Jiráček
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Irena Selicharová
- From the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
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8
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Fabre B, Pícha J, Selicharová I, Žáková L, Chrudinová M, Hajduch J, Jiráček J. Probing Tripodal Peptide Scaffolds as Insulin and IGF-1 Receptor Ligands. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Benjamin Fabre
- Institute of Organic Chemistry and Biochemistry; Czech Academy of Sciences, v.v.i.; Flemingovo n. 2, 16610 6 Praha Czech Republic
| | - Jan Pícha
- Institute of Organic Chemistry and Biochemistry; Czech Academy of Sciences, v.v.i.; Flemingovo n. 2, 16610 6 Praha Czech Republic
| | - Irena Selicharová
- Institute of Organic Chemistry and Biochemistry; Czech Academy of Sciences, v.v.i.; Flemingovo n. 2, 16610 6 Praha Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry; Czech Academy of Sciences, v.v.i.; Flemingovo n. 2, 16610 6 Praha Czech Republic
| | - Martina Chrudinová
- Institute of Organic Chemistry and Biochemistry; Czech Academy of Sciences, v.v.i.; Flemingovo n. 2, 16610 6 Praha Czech Republic
| | - Jan Hajduch
- Institute of Organic Chemistry and Biochemistry; Czech Academy of Sciences, v.v.i.; Flemingovo n. 2, 16610 6 Praha Czech Republic
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry; Czech Academy of Sciences, v.v.i.; Flemingovo n. 2, 16610 6 Praha Czech Republic
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9
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Akbarian M, Ghasemi Y, Uversky VN, Yousefi R. Chemical modifications of insulin: Finding a compromise between stability and pharmaceutical performance. Int J Pharm 2018; 547:450-468. [DOI: 10.1016/j.ijpharm.2018.06.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 02/07/2023]
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10
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Ong SC, Belgi A, van Lierop B, Delaine C, Andrikopoulos S, MacRaild CA, Norton RS, Haworth NL, Robinson AJ, Forbes BE. Probing the correlation between insulin activity and structural stability through introduction of the rigid A6-A11 bond. J Biol Chem 2018; 293:11928-11943. [PMID: 29899115 DOI: 10.1074/jbc.ra118.002486] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 06/10/2018] [Indexed: 11/06/2022] Open
Abstract
The development of fast-acting and highly stable insulin analogues is challenging. Insulin undergoes structural transitions essential for binding and activation of the insulin receptor (IR), but these conformational changes can also affect insulin stability. Previously, we substituted the insulin A6-A11 cystine with a rigid, non-reducible C=C linkage ("dicarba" linkage). A cis-alkene permitted the conformational flexibility of the A-chain N-terminal helix necessary for high-affinity IR binding, resulting in surprisingly rapid activity in vivo Here, we show that, unlike the rapidly acting LysB28ProB29 insulin analogue (KP insulin), cis-dicarba insulin is not inherently monomeric. We also show that cis-dicarba KP insulin lowers blood glucose levels even more rapidly than KP insulin, suggesting that an inability to oligomerize is not responsible for the observed rapid activity onset of cis-dicarba analogues. Although rapid-acting, neither dicarba species is stable, as assessed by fibrillation and thermodynamics assays. MALDI analyses and molecular dynamics simulations of cis-dicarba insulin revealed a previously unidentified role of the A6-A11 linkage in insulin conformational dynamics. By controlling the conformational flexibility of the insulin B-chain helix, this linkage affects overall insulin structural stability. This effect is independent of its regulation of the A-chain N-terminal helix flexibility necessary for IR engagement. We conclude that high-affinity IR binding, rapid in vivo activity, and insulin stability can be regulated by the specific conformational arrangement of the A6-A11 linkage. This detailed understanding of insulin's structural dynamics may aid in the future design of rapid-acting insulin analogues with improved stability.
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Affiliation(s)
- Shee Chee Ong
- From the College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia
| | - Alessia Belgi
- the School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Bianca van Lierop
- the School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Carlie Delaine
- From the College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia
| | - Sofianos Andrikopoulos
- the Department of Medicine, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Christopher A MacRaild
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Naomi L Haworth
- the School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.,the Research School of Chemistry, Australian National University, Acton, Australian Capital Territory 2601, Australia, and.,the School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Victoria 3216, Australia
| | - Andrea J Robinson
- the School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Briony E Forbes
- From the College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia,
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11
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Computational study of the activity, dynamics, energetics and conformations of insulin analogues using molecular dynamics simulations: Application to hyperinsulinemia and the critical residue B26. Biochem Biophys Rep 2017; 11:182-190. [PMID: 28955783 PMCID: PMC5614686 DOI: 10.1016/j.bbrep.2017.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 04/13/2017] [Indexed: 12/15/2022] Open
Abstract
Due to the increasing prevalence of diabetes, finding therapeutic analogues for insulin has become an urgent issue. While many experimental studies have been performed towards this end, they have limited scope to examine all aspects of the effect of a mutation. Computational studies can help to overcome these limitations, however, relatively few studies that focus on insulin analogues have been performed to date. Here, we present a comprehensive computational study of insulin analogues-three mutant insulins that have been identified with hyperinsulinemia and three mutations on the critical B26 residue that exhibit similar binding affinity to the insulin receptor-using molecular dynamics simulations with the aim of predicting how mutations of insulin affect its activity, dynamics, energetics and conformations. The time evolution of the conformers is studied in long simulations. The probability density function and potential of mean force calculations are performed on each insulin analogue to unravel the effect of mutations on the dynamics and energetics of insulin activation. Our conformational study can decrypt the key features and molecular mechanisms that are responsible for an enhanced or reduced activity of an insulin analogue. We find two key results: 1) hyperinsulinemia may be due to the drastically reduced activity (and binding affinity) of the mutant insulins. 2) Y26BS and Y26BE are promising therapeutic candidates for insulin as they are more active than WT-insulin. The analysis in this work can be readily applied to any set of mutations on insulin to guide development of more effective therapeutic analogues.
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12
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Fabre B, Pícha J, Vaněk V, Selicharová I, Chrudinová M, Collinsová M, Žáková L, Buděšínský M, Jiráček J. Synthesis and Evaluation of a Library of Trifunctional Scaffold-Derived Compounds as Modulators of the Insulin Receptor. ACS COMBINATORIAL SCIENCE 2016; 18:710-722. [PMID: 27936668 DOI: 10.1021/acscombsci.6b00132] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We designed a combinatorial library of trifunctional scaffold-derived compounds, which were derivatized with 30 different in-house-made azides. The compounds were proposed to mimic insulin receptor (IR)-binding epitopes in the insulin molecule and bind to and activate this receptor. This work has enabled us to test our synthetic and biological methodology and to prove its robustness and reliability for the solid-phase synthesis and testing of combinatorial libraries of the trifunctional scaffold-derived compounds. Our effort resulted in the discovery of two compounds, which were able to weakly induce the autophosphorylation of IR and weakly bind to this receptor at a 0.1 mM concentration. Despite these modest biological results, which well document the well-known difficulty in modulating protein-protein interactions, this study represents a unique example of targeting the IR with a set of nonpeptide compounds that were specifically designed and synthesized for this purpose. We believe that this work can open new perspectives for the development of next-generation insulin mimetics based on the scaffold structure.
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Affiliation(s)
- Benjamin Fabre
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
| | - Jan Pícha
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
| | - Václav Vaněk
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
| | - Irena Selicharová
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
| | - Martina Chrudinová
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
| | - Michaela Collinsová
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
| | - Miloš Buděšínský
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
| | - Jiří Jiráček
- Institute of Organic Chemistry
and Biochemistry, Czech Academy of Sciences, Flemingovo n. 2, 16610 Praha 6, Czech Republic
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13
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Papaioannou A, Kuyucak S, Kuncic Z. Elucidating the Activation Mechanism of the Insulin-Family Proteins with Molecular Dynamics Simulations. PLoS One 2016; 11:e0161459. [PMID: 27548502 PMCID: PMC4993506 DOI: 10.1371/journal.pone.0161459] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Accepted: 08/05/2016] [Indexed: 12/27/2022] Open
Abstract
The insulin-family proteins bind to their own receptors, but insulin-like growth factor II (IGF-II) can also bind to the A isoform of the insulin receptor (IR-A), activating unique and alternative signaling pathways from those of insulin. Although extensive studies of insulin have revealed that its activation is associated with the opening of the B chain-C terminal (BC-CT), the activation mechanism of the insulin-like growth factors (IGFs) still remains unknown. Here, we present the first comprehensive study of the insulin-family proteins comparing their activation process and mechanism using molecular dynamics simulations to reveal new insights into their specificity to the insulin receptor. We have found that all the proteins appear to exhibit similar stochastic dynamics in their conformational change to an active state. For the IGFs, our simulations show that activation involves two opening locations: the opening of the BC-CT section away from the core, similar to insulin; and the additional opening of the BC-CT section away from the C domain. Furthermore, we have found that these two openings occur simultaneously in IGF-I, but not in IGF-II, where they can occur independently. This suggests that the BC-CT section and the C domain behave as a unified domain in IGF-I, but as two independent domains in IGF-II during the activation process, implying that the IGFs undergo different activation mechanisms for receptor binding. The probabilities of the active and inactive states of the proteins suggest that IGF-II is hyperactive compared to IGF-I. The hinge residue and the hydrophobic interactions in the core are found to play a critical role in the stability and activity of IGFs. Overall, our simulations have elucidated the crucial differences and similarities in the activation mechanisms of the insulin-family proteins, providing new insights into the molecular mechanisms responsible for the observed differences between IGF-I and IGF-II in receptor binding.
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Affiliation(s)
- Anastasios Papaioannou
- Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
- School of Physics, University of Sydney, Sydney, NSW, Australia
- * E-mail: (AP); (ZK)
| | - Serdar Kuyucak
- School of Physics, University of Sydney, Sydney, NSW, Australia
| | - Zdenka Kuncic
- Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
- School of Physics, University of Sydney, Sydney, NSW, Australia
- * E-mail: (AP); (ZK)
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14
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Křížková K, Chrudinová M, Povalová A, Selicharová I, Collinsová M, Vaněk V, Brzozowski AM, Jiráček J, Žáková L. Insulin–Insulin-like Growth Factors Hybrids as Molecular Probes of Hormone:Receptor Binding Specificity. Biochemistry 2016; 55:2903-13. [DOI: 10.1021/acs.biochem.6b00140] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Květoslava Křížková
- Institute
of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic v.v.i., Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
- Charles University in Prague, Faculty of Science,
Department of Biochemistry, Hlavova 8, 128 43 Praha 2, Czech Republic
| | - Martina Chrudinová
- Institute
of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic v.v.i., Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
- Charles University in Prague, Faculty of Science,
Department of Biochemistry, Hlavova 8, 128 43 Praha 2, Czech Republic
| | - Anna Povalová
- Institute
of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic v.v.i., Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
- Charles University in Prague, Faculty of Science,
Department of Biochemistry, Hlavova 8, 128 43 Praha 2, Czech Republic
| | - Irena Selicharová
- Institute
of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic v.v.i., Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
| | - Michaela Collinsová
- Institute
of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic v.v.i., Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
| | - Václav Vaněk
- Institute
of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic v.v.i., Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
| | - Andrzej M. Brzozowski
- York
Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Jiří Jiráček
- Institute
of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic v.v.i., Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
| | - Lenka Žáková
- Institute
of Organic Chemistry and Biochemistry, Academy of Science of the Czech Republic v.v.i., Flemingovo nám. 2, 166 10 Praha 6, Czech Republic
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15
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Pandyarajan V, Phillips NB, Rege N, Lawrence MC, Whittaker J, Weiss MA. Contribution of TyrB26 to the Function and Stability of Insulin: STRUCTURE-ACTIVITY RELATIONSHIPS AT A CONSERVED HORMONE-RECEPTOR INTERFACE. J Biol Chem 2016; 291:12978-90. [PMID: 27129279 DOI: 10.1074/jbc.m115.708347] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Indexed: 11/06/2022] Open
Abstract
Crystallographic studies of insulin bound to receptor domains have defined the primary hormone-receptor interface. We investigated the role of Tyr(B26), a conserved aromatic residue at this interface. To probe the evolutionary basis for such conservation, we constructed 18 variants at B26. Surprisingly, non-aromatic polar or charged side chains (such as Glu, Ser, or ornithine (Orn)) conferred high activity, whereas the weakest-binding analogs contained Val, Ile, and Leu substitutions. Modeling of variant complexes suggested that the B26 side chains pack within a shallow depression at the solvent-exposed periphery of the interface. This interface would disfavor large aliphatic side chains. The analogs with highest activity exhibited reduced thermodynamic stability and heightened susceptibility to fibrillation. Perturbed self-assembly was also demonstrated in studies of the charged variants (Orn and Glu); indeed, the Glu(B26) analog exhibited aberrant aggregation in either the presence or absence of zinc ions. Thus, although Tyr(B26) is part of insulin's receptor-binding surface, our results suggest that its conservation has been enjoined by the aromatic ring's contributions to native stability and self-assembly. We envisage that such classical structural relationships reflect the implicit threat of toxic misfolding (rather than hormonal function at the receptor level) as a general evolutionary determinant of extant protein sequences.
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Affiliation(s)
| | | | | | - Michael C Lawrence
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Victoria 3052, Australia, Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | | | - Michael A Weiss
- From the Departments of Biochemistry, Medicine, and Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106,
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16
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Viková J, Collinsová M, Kletvíková E, Buděšínský M, Kaplan V, Žáková L, Veverka V, Hexnerová R, Aviñó RJT, Straková J, Selicharová I, Vaněk V, Wright DW, Watson CJ, Turkenburg JP, Brzozowski AM, Jiráček J. Rational steering of insulin binding specificity by intra-chain chemical crosslinking. Sci Rep 2016; 6:19431. [PMID: 26792393 PMCID: PMC4726324 DOI: 10.1038/srep19431] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 12/11/2015] [Indexed: 12/14/2022] Open
Abstract
Insulin is a key hormone of human metabolism with major therapeutic importance for both types of diabetes. New insulin analogues with more physiological profiles and better glycemic control are needed, especially analogues that preferentially bind to the metabolic B-isoform of insulin receptor (IR-B). Here, we aimed to stabilize and modulate the receptor-compatible conformation of insulin by covalent intra-chain crosslinking within its B22-B30 segment, using the Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction of azides and alkynes. This approach resulted in 14 new, systematically crosslinked insulin analogues whose structures and functions were extensively characterized and correlated. One of the analogues, containing a B26-B29 triazole bridge, was highly active in binding to both IR isoforms, with a significant preference for IR-B. Our results demonstrate the potential of chemistry-driven modulation of insulin function, also shedding new light on the functional importance of hormone's B-chain C-terminus for its IR-B specificity.
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Affiliation(s)
- Jitka Viková
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Michaela Collinsová
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Emília Kletvíková
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Miloš Buděšínský
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Vojtěch Kaplan
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Václav Veverka
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Rozálie Hexnerová
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Roberto J. Tarazona Aviñó
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Jana Straková
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Irena Selicharová
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Václav Vaněk
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
| | - Daniel W. Wright
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Christopher J. Watson
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Johan P. Turkenburg
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Andrzej M. Brzozowski
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, the Czech Academy of Sciences, v.v.i., Flemingovo n. 2, 166 10 Praha 6, Czech Republic
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17
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Papaioannou A, Kuyucak S, Kuncic Z. Molecular Dynamics Simulations of Insulin: Elucidating the Conformational Changes that Enable Its Binding. PLoS One 2015; 10:e0144058. [PMID: 26629689 PMCID: PMC4668001 DOI: 10.1371/journal.pone.0144058] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 11/12/2015] [Indexed: 01/30/2023] Open
Abstract
A sequence of complex conformational changes is required for insulin to bind to the insulin receptor. Recent experimental evidence points to the B chain C-terminal (BC-CT) as the location of these changes in insulin. Here, we present molecular dynamics simulations of insulin that reveal new insights into the structural changes occurring in the BC-CT. We find three key results: 1) The opening of the BC-CT is inherently stochastic and progresses through an open and then a “wide-open” conformation—the wide-open conformation is essential for receptor binding, but occurs only rarely. 2) The BC-CT opens with a zipper-like mechanism, with a hinge at the Phe24 residue, and is maintained in the dominant closed/inactive state by hydrophobic interactions of the neighboring Tyr26, the critical residue where opening of the BC-CT (activation of insulin) is initiated. 3) The mutation Y26N is a potential candidate as a therapeutic insulin analogue. Overall, our results suggest that the binding of insulin to its receptor is a highly dynamic and stochastic process, where initial docking occurs in an open conformation and full binding is facilitated through interactions of insulin receptor residues with insulin in its wide-open conformation.
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Affiliation(s)
- Anastasios Papaioannou
- Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
- School of Physics, University of Sydney, Sydney, NSW, Australia
- * E-mail:
| | - Serdar Kuyucak
- School of Physics, University of Sydney, Sydney, NSW, Australia
| | - Zdenka Kuncic
- Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
- School of Physics, University of Sydney, Sydney, NSW, Australia
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18
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Affiliation(s)
- Pierre De Meyts
- Department of Diabetes Biology; Novo Nordisk A/S; Måløv Denmark
- De Meyts R&D Consulting; Kraainem; Belgium
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19
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Bathula SR, Akondi SM, Mainkar PS, Chandrasekhar S. “Pruning of biomolecules and natural products (PBNP)”: an innovative paradigm in drug discovery. Org Biomol Chem 2015; 13:6432-48. [DOI: 10.1039/c5ob00403a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Smart Schneider: ‘Nature’ is the most intelligent tailor with an ability to utilize the resources. Researchers are still at an infant stage learning this art. The present review highlights some of the man made pruning of bio-molecules and NPs (PBNP) in finding chemicals with a better therapeutic index.
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Affiliation(s)
- Surendar Reddy Bathula
- Division of Natural Products Chemistry CSIR-Indian Institute of Chemical Technology
- Hyderabad
- 500007 India
| | - Srirama Murthy Akondi
- Division of Natural Products Chemistry CSIR-Indian Institute of Chemical Technology
- Hyderabad
- 500007 India
| | - Prathama S. Mainkar
- Division of Natural Products Chemistry CSIR-Indian Institute of Chemical Technology
- Hyderabad
- 500007 India
| | - Srivari Chandrasekhar
- Division of Natural Products Chemistry CSIR-Indian Institute of Chemical Technology
- Hyderabad
- 500007 India
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20
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Křížková K, Veverka V, Maletínská L, Hexnerová R, Brzozowski AM, Jiráček J, Žáková L. Structural and functional study of the GlnB22-insulin mutant responsible for maturity-onset diabetes of the young. PLoS One 2014; 9:e112883. [PMID: 25423173 PMCID: PMC4244080 DOI: 10.1371/journal.pone.0112883] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 10/21/2014] [Indexed: 12/04/2022] Open
Abstract
The insulin gene mutation c.137G>A (R46Q), which changes an arginine at the B22 position of the mature hormone to glutamine, causes the monogenic diabetes variant maturity-onset diabetes of the young (MODY). In MODY patients, this mutation is heterozygous, and both mutant and wild-type (WT) human insulin are produced simultaneously. However, the patients often depend on administration of exogenous insulin. In this study, we chemically synthesized the MODY mutant [GlnB22]-insulin and characterized its biological and structural properties. The chemical synthesis of this insulin analogue revealed that its folding ability is severely impaired. In vitro and in vivo tests showed that its binding affinity and biological activity are reduced (both approximately 20% that of human insulin). Comparison of the solution structure of [GlnB22]-insulin with the solution structure of native human insulin revealed that the most significant structural effect of the mutation is distortion of the B20-B23 β-turn, leading to liberation of the B chain C-terminus from the protein core. The distortion of the B20-B23 β-turn is caused by the extended conformational freedom of the GlnB22 side chain, which is no longer anchored in a hydrogen bonding network like the native ArgB22. The partially disordered [GlnB22]-insulin structure appears to be one reason for the reduced binding potency of this mutant and may also be responsible for its low folding efficiency in vivo. The altered orientation and flexibility of the B20-B23 β-turn may interfere with the formation of disulfide bonds in proinsulin bearing the R46Q (GlnB22) mutation. This may also have a negative effect on the WT proinsulin simultaneously biosynthesized in β-cells and therefore play a major role in the development of MODY in patients producing [GlnB22]-insulin.
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Affiliation(s)
- Květoslava Křížková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Václav Veverka
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Lenka Maletínská
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Rozálie Hexnerová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Andrzej M. Brzozowski
- York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
- * E-mail:
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21
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Žáková L, Kletvíková E, Lepšík M, Collinsová M, Watson CJ, Turkenburg JP, Jiráček J, Brzozowski AM. Human insulin analogues modified at the B26 site reveal a hormone conformation that is undetected in the receptor complex. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2014; 70:2765-74. [PMID: 25286859 PMCID: PMC4188015 DOI: 10.1107/s1399004714017775] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 08/01/2014] [Indexed: 11/10/2022]
Abstract
The structural characterization of the insulin-insulin receptor (IR) interaction still lacks the conformation of the crucial B21-B30 insulin region, which must be different from that in its storage forms to ensure effective receptor binding. Here, it is shown that insulin analogues modified by natural amino acids at the TyrB26 site can represent an active form of this hormone. In particular, [AsnB26]-insulin and [GlyB26]-insulin attain a B26-turn-like conformation that differs from that in all known structures of the native hormone. It also matches the receptor interface, avoiding substantial steric clashes. This indicates that insulin may attain a B26-turn-like conformation upon IR binding. Moreover, there is an unexpected, but significant, binding specificity of the AsnB26 mutant for predominantly the metabolic B isoform of the receptor. As it is correlated with the B26 bend of the B-chain of the hormone, the structures of AsnB26 analogues may provide the first structural insight into the structural origins of differential insulin signalling through insulin receptor A and B isoforms.
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Affiliation(s)
- Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Emília Kletvíková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Martin Lepšík
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Michaela Collinsová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Christopher J. Watson
- York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5DD, England
| | - Johan P. Turkenburg
- York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5DD, England
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Andrzej M. Brzozowski
- York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5DD, England
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22
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Kosinová L, Veverka V, Novotná P, Collinsová M, Urbanová M, Moody NR, Turkenburg JP, Jiráček J, Brzozowski AM, Žáková L. Insight into the structural and biological relevance of the T/R transition of the N-terminus of the B-chain in human insulin. Biochemistry 2014; 53:3392-402. [PMID: 24819248 PMCID: PMC4047818 DOI: 10.1021/bi500073z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
![]()
The N-terminus of the B-chain of
insulin may adopt two alternative
conformations designated as the T- and R-states. Despite the recent
structural insight into insulin–insulin receptor (IR) complexes,
the physiological relevance of the T/R transition is still unclear.
Hence, this study focused on the rational design, synthesis, and characterization
of human insulin analogues structurally locked in expected R- or T-states.
Sites B3, B5, and B8, capable of affecting the conformation of the
N-terminus of the B-chain, were subjects of rational substitutions
with amino acids with specific allowed and disallowed dihedral φ
and ψ main-chain angles. α-Aminoisobutyric acid was systematically
incorporated into positions B3, B5, and B8 for stabilization of the
R-state, and N-methylalanine and d-proline
amino acids were introduced at position B8 for stabilization of the
T-state. IR affinities of the analogues were compared and correlated
with their T/R transition ability and analyzed against their crystal
and nuclear magnetic resonance structures. Our data revealed that
(i) the T-like state is indeed important for the folding efficiency
of (pro)insulin, (ii) the R-state is most probably incompatible with
an active form of insulin, (iii) the R-state cannot be induced or
stabilized by a single substitution at a specific site, and (iv) the
B1–B8 segment is capable of folding into a variety of low-affinity
T-like states. Therefore, we conclude that the active conformation
of the N-terminus of the B-chain must be different from the “classical”
T-state and that a substantial flexibility of the B1–B8 segment,
where GlyB8 plays a key role, is a crucial prerequisite for an efficient
insulin–IR interaction.
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Affiliation(s)
- Lucie Kosinová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic , v.v.i., Flemingovo nám 2, 166 10 Prague 6, Czech Republic
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23
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Nash A, Soheili A, Tambar UK. Stereoselective Synthesis of Functionalized Cyclic Amino Acid Derivatives via a [2,3]-Stevens Rearrangement and Ring-Closing Metathesis. Org Lett 2013; 15:4770-3. [DOI: 10.1021/ol402129h] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Aaron Nash
- Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9038, United States
| | - Arash Soheili
- Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9038, United States
| | - Uttam K. Tambar
- Department of Biochemistry, The University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9038, United States
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24
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Žáková L, Kletvíková E, Veverka V, Lepsík M, Watson CJ, Turkenburg JP, Jirácek J, Brzozowski AM. Structural integrity of the B24 site in human insulin is important for hormone functionality. J Biol Chem 2013; 288:10230-40. [PMID: 23447530 DOI: 10.1074/jbc.m112.448050] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Despite the recent first structural insight into the insulin-insulin receptor complex, the role of the C terminus of the B-chain of insulin in this assembly remains unresolved. Previous studies have suggested that this part of insulin must rearrange to reveal amino acids crucial for interaction with the receptor. The role of the invariant Phe(B24), one of the key residues of the hormone, in this process remains unclear. For example, the B24 site functionally tolerates substitutions to D-amino acids but not to L-amino acids. Here, we prepared and characterized a series of B24-modified insulin analogues, also determining the structures of [D-HisB24]-insulin and [HisB24]-insulin. The inactive [HisB24]-insulin molecule is remarkably rigid due to a tight accommodation of the L-His side chain in the B24 binding pocket that results in the stronger tethering of B25-B28 residues to the protein core. In contrast, the highly active [D-HisB24]-insulin is more flexible, and the reverse chirality of the B24C(α) atom swayed the D-His(B24) side chain into the solvent. Furthermore, the pocket vacated by Phe(B24) is filled by Phe(B25), which mimics the Phe(B24) side and main chains. The B25→B24 downshift results in a subsequent downshift of Tyr(B26) into the B25 site and the departure of B26-B30 residues away from the insulin core. Our data indicate the importance of the aromatic L-amino acid at the B24 site and the structural invariance/integrity of this position for an effective binding of insulin to its receptor. Moreover, they also suggest limited, B25-B30 only, unfolding of the C terminus of the B-chain upon insulin activation.
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Affiliation(s)
- Lenka Žáková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
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25
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Vashisth H, Abrams CF. All-atom structural models of insulin binding to the insulin receptor in the presence of a tandem hormone-binding element. Proteins 2013; 81:1017-30. [PMID: 23348915 DOI: 10.1002/prot.24255] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 12/11/2012] [Accepted: 01/04/2013] [Indexed: 11/10/2022]
Abstract
Insulin regulates blood glucose levels in higher organisms by binding to and activating insulin receptor (IR), a constitutively homodimeric glycoprotein of the receptor tyrosine kinase (RTK) superfamily. Therapeutic efforts in treating diabetes have been significantly impeded by the absence of structural information on the activated form of the insulin/IR complex. Mutagenesis and photo-crosslinking experiments and structural information on insulin and apo-IR strongly suggest that the dual-chain insulin molecule, unlike the related single-chain insulin-like growth factors, binds to IR in a very different conformation than what is displayed in storage forms of the hormone. In particular, hydrophobic residues buried in the core of the folded insulin molecule engage the receptor. There is also the possibility of plasticity in the receptor structure based on these data, which may in part be due to rearrangement of the so-called CT-peptide, a tandem hormone-binding element of IR. These possibilities provide opportunity for large-scale molecular modeling to contribute to our understanding of this system. Using various atomistic simulation approaches, we have constructed all-atom structural models of hormone/receptor complexes in the presence of CT in its crystallographic position and a thermodynamically favorable displaced position. In the "displaced-CT" complex, many more insulin-receptor contacts suggested by experiments are satisfied, and our simulations also suggest that R-insulin potentially represents the receptor-bound form of hormone. The results presented in this work have further implications for the design of receptor-specific agonists/antagonists.
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Affiliation(s)
- Harish Vashisth
- Department of Chemistry and Biophysics Program, University of Michigan, Ann Arbor, Michigan, USA.
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26
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Menting JG, Whittaker J, Margetts MB, Whittaker LJ, Kong GKW, Smith BJ, Watson CJ, Záková L, Kletvíková E, Jiráček J, Chan SJ, Steiner DF, Dodson GG, Brzozowski AM, Weiss MA, Ward CW, Lawrence MC. How insulin engages its primary binding site on the insulin receptor. Nature 2013; 493:241-5. [PMID: 23302862 DOI: 10.1038/nature11781] [Citation(s) in RCA: 287] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 11/12/2012] [Indexed: 12/24/2022]
Abstract
Insulin receptor signalling has a central role in mammalian biology, regulating cellular metabolism, growth, division, differentiation and survival. Insulin resistance contributes to the pathogenesis of type 2 diabetes mellitus and the onset of Alzheimer's disease; aberrant signalling occurs in diverse cancers, exacerbated by cross-talk with the homologous type 1 insulin-like growth factor receptor (IGF1R). Despite more than three decades of investigation, the three-dimensional structure of the insulin-insulin receptor complex has proved elusive, confounded by the complexity of producing the receptor protein. Here we present the first view, to our knowledge, of the interaction of insulin with its primary binding site on the insulin receptor, on the basis of four crystal structures of insulin bound to truncated insulin receptor constructs. The direct interaction of insulin with the first leucine-rich-repeat domain (L1) of insulin receptor is seen to be sparse, the hormone instead engaging the insulin receptor carboxy-terminal α-chain (αCT) segment, which is itself remodelled on the face of L1 upon insulin binding. Contact between insulin and L1 is restricted to insulin B-chain residues. The αCT segment displaces the B-chain C-terminal β-strand away from the hormone core, revealing the mechanism of a long-proposed conformational switch in insulin upon receptor engagement. This mode of hormone-receptor recognition is novel within the broader family of receptor tyrosine kinases. We support these findings by photo-crosslinking data that place the suggested interactions into the context of the holoreceptor and by isothermal titration calorimetry data that dissect the hormone-insulin receptor interface. Together, our findings provide an explanation for a wealth of biochemical data from the insulin receptor and IGF1R systems relevant to the design of therapeutic insulin analogues.
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Affiliation(s)
- John G Menting
- Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Victoria 3052, Australia
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Morcavallo A, Genua M, Palummo A, Kletvikova E, Jiracek J, Brzozowski AM, Iozzo RV, Belfiore A, Morrione A. Insulin and insulin-like growth factor II differentially regulate endocytic sorting and stability of insulin receptor isoform A. J Biol Chem 2012; 287:11422-36. [PMID: 22318726 DOI: 10.1074/jbc.m111.252478] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The insulin receptor isoform A (IR-A) binds both insulin and insulin-like growth factor (IGF)-II, although the affinity for IGF-II is 3-10-fold lower than insulin depending on a cell and tissue context. Notably, in mouse embryonic fibroblasts lacking the IGF-IR and expressing solely the IR-A (R-/IR-A), IGF-II is a more potent mitogen than insulin. As receptor endocytosis and degradation provide spatial and temporal regulation of signaling events, we hypothesized that insulin and IGF-II could affect IR-A biological responses by differentially regulating IR-A trafficking. Using R-/IR-A cells, we discovered that insulin evoked significant IR-A internalization, a process modestly affected by IGF-II. However, the differential internalization was not due to IR-A ubiquitination. Notably, prolonged stimulation of R-/IR-A cells with insulin, but not with IGF-II, targeted the receptor to a degradative pathway. Similarly, the docking protein insulin receptor substrate 1 (IRS-1) was down-regulated after prolonged insulin but not IGF-II exposure. Similar results were also obtained in experiments using [NMeTyr(B26)]-insulin, an insulin analog with IR-A binding affinity similar to IGF-II. Finally, we discovered that IR-A was internalized through clathrin-dependent and -independent pathways, which differentially regulated the activation of downstream effectors. Collectively, our results suggest that a lower affinity of IGF-II for the IR-A promotes lower IR-A phosphorylation and activation of early downstream effectors vis à vis insulin but may protect IR-A and IRS-1 from down-regulation thereby evoking sustained and robust mitogenic stimuli.
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Affiliation(s)
- Alaide Morcavallo
- Department of Urology and Endocrine Mechanisms and Hormone Action Program, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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Antolíková E, Žáková L, Turkenburg JP, Watson CJ, Hančlová I, Šanda M, Cooper A, Kraus T, Brzozowski AM, Jiráček J. Non-equivalent role of inter- and intramolecular hydrogen bonds in the insulin dimer interface. J Biol Chem 2011; 286:36968-77. [PMID: 21880708 PMCID: PMC3196076 DOI: 10.1074/jbc.m111.265249] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 08/03/2011] [Indexed: 11/06/2022] Open
Abstract
Apart from its role in insulin receptor (IR) activation, the C terminus of the B-chain of insulin is also responsible for the formation of insulin dimers. The dimerization of insulin plays an important role in the endogenous delivery of the hormone and in the administration of insulin to patients. Here, we investigated insulin analogues with selective N-methylations of peptide bond amides at positions B24, B25, or B26 to delineate their structural and functional contribution to the dimer interface. All N-methylated analogues showed impaired binding affinities to IR, which suggests a direct IR-interacting role for the respective amide hydrogens. The dimerization capabilities of analogues were investigated by isothermal microcalorimetry. Selective N-methylations of B24, B25, or B26 amides resulted in reduced dimerization abilities compared with native insulin (K(d) = 8.8 μM). Interestingly, although the N-methylation in [NMeTyrB26]-insulin or [NMePheB24]-insulin resulted in K(d) values of 142 and 587 μM, respectively, the [NMePheB25]-insulin did not form dimers even at high concentrations. This effect may be attributed to the loss of intramolecular hydrogen bonding between NHB25 and COA19, which connects the B-chain β-strand to the core of the molecule. The release of the B-chain β-strand from this hydrogen bond lock may result in its higher mobility, thereby shifting solution equilibrium toward the monomeric state of the hormone. The study was complemented by analyses of two novel analogue crystal structures. All examined analogues crystallized only in the most stable R(6) form of insulin oligomers (even if the dimer interface was totally disrupted), confirming the role of R(6)-specific intra/intermolecular interactions for hexamer stability.
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Affiliation(s)
- Emília Antolíková
- From the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Lenka Žáková
- From the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Johan P. Turkenburg
- the York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5YW, United Kingdom, and
| | - Christopher J. Watson
- the York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5YW, United Kingdom, and
| | - Ivona Hančlová
- From the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Miloslav Šanda
- From the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Alan Cooper
- the School of Chemistry, Glasgow University, College of Science and Engineering, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Tomáš Kraus
- From the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - A. Marek Brzozowski
- the York Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5YW, United Kingdom, and
| | - Jiří Jiráček
- From the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
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Glendorf T, Stidsen CE, Norrman M, Nishimura E, Sørensen AR, Kjeldsen T. Engineering of insulin receptor isoform-selective insulin analogues. PLoS One 2011; 6:e20288. [PMID: 21625452 PMCID: PMC3098868 DOI: 10.1371/journal.pone.0020288] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Accepted: 04/28/2011] [Indexed: 11/19/2022] Open
Abstract
Background The insulin receptor (IR) exists in two isoforms, A and B, and the isoform expression pattern is tissue-specific. The C-terminus of the insulin B chain is important for receptor binding and has been shown to contact the IR just adjacent to the region where the A and B isoforms differ. The aim of this study was to investigate the importance of the C-terminus of the B chain in IR isoform binding in order to explore the possibility of engineering tissue-specific/liver-specific insulin analogues. Methodology/Principal Findings Insulin analogue libraries were constructed by total amino acid scanning mutagenesis. The relative binding affinities for the A and B isoform of the IR were determined by competition assays using scintillation proximity assay technology. Structural information was obtained by X-ray crystallography. Introduction of B25A or B25N mutations resulted in analogues with a 2-fold preference for the B compared to the A isoform, whereas the opposite was observed with a B25Y substitution. An acidic amino acid residue at position B27 caused an additional 2-fold selective increase in affinity for the receptor B isoform for analogues bearing a B25N mutation. Furthermore, the combination of B25H with either B27D or B27E also resulted in B isoform-preferential analogues (2-fold preference) even though the corresponding single mutation analogues displayed no differences in relative isoform binding affinity. Conclusions/Significance We have discovered a new class of IR isoform-selective insulin analogues with 2–4-fold differences in relative binding affinities for either the A or the B isoform of the IR compared to human insulin. Our results demonstrate that a mutation at position B25 alone or in combination with a mutation at position B27 in the insulin molecule confers IR isoform selectivity. Isoform-preferential analogues may provide new opportunities for developing insulin analogues with improved clinical benefits.
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Affiliation(s)
- Tine Glendorf
- Diabetes Research Unit, Novo Nordisk A/S, Maaloev, Denmark.
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Implications for the active form of human insulin based on the structural convergence of highly active hormone analogues. Proc Natl Acad Sci U S A 2010; 107:1966-70. [PMID: 20133841 DOI: 10.1073/pnas.0911785107] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Insulin is a key protein hormone that regulates blood glucose levels and, thus, has widespread impact on lipid and protein metabolism. Insulin action is manifested through binding of its monomeric form to the Insulin Receptor (IR). At present, however, our knowledge about the structural behavior of insulin is based upon inactive, multimeric, and storage-like states. The active monomeric structure, when in complex with the receptor, must be different as the residues crucial for the interactions are buried within the multimeric forms. Although the exact nature of the insulin's induced-fit is unknown, there is strong evidence that the C-terminal part of the B-chain is a dynamic element in insulin activation and receptor binding. Here, we present the design and analysis of highly active (200-500%) insulin analogues that are truncated at residue 26 of the B-chain (B(26)). They show a structural convergence in the form of a new beta-turn at B(24)-B(26). We propose that the key element in insulin's transition, from an inactive to an active state, may be the formation of the beta-turn at B(24)-B(26) associated with a trans to cis isomerisation at the B(25)-B(26) peptide bond. Here, this turn is achieved with N-methylated L-amino acids adjacent to the trans to cis switch at the B(25)-B(26) peptide bond or by the insertion of certain D-amino acids at B(26). The resultant conformational changes unmask previously buried amino acids that are implicated in IR binding and provide structural details for new approaches in rational design of ligands effective in combating diabetes.
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