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Yang H, Yang M, Zhang Y, Shi Z, Zhang X, Zhang C. Elevated serum IGFBP-1 levels correlate with cognitive deficits in treatment-resistant and chronic medicated schizophrenia patients. Cytokine 2024; 182:156728. [PMID: 39126767 DOI: 10.1016/j.cyto.2024.156728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 05/31/2024] [Accepted: 08/05/2024] [Indexed: 08/12/2024]
Abstract
BACKGROUND Schizophrenia is a debilitating psychiatric disorder with diverse cognitive impairments. Insulin-like growth factor binding protein 1 (IGFBP-1), a ubiquitous negative regulator of IGF signaling, crosses the blood-brain barrier after peripheral synthesis. Given the crucial role of IGF signaling in cognitive function, we reasoned that altered serum IGFBP-1 concentrations might be associated with cognitive impairments in schizophrenia. To test this hypothesis, we examined the relationship between serum IGFBP-1 levels and cognitive performance in both medicated and treatment-resistant schizophrenia (TRS) patients. METHODS Serum IGFBP-1 was measured in 31 TRS patients, 49 chronic medicated schizophrenia (CMS) patients, and 53 healthy controls. Clinical symptom severity was evaluated using the Positive and Negative Syndrome Scale (PANSS) and cognitive functions using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). RESULTS Both TRS and CMS patients exhibited cognitive deficits compared to healthy controls (p < 0.05). Serum IGFBP-1 concentration differed significantly among groups (F=36.805, p < 0.001) and post hoc tests demonstrated significantly higher concentrations in both schizophrenia groups compared to controls (p < 0.001). Further, serum IGFBP-1 concentration was higher in the TRS group than the CMS group (p = 0.048). Correlation analysis identified a significant relationship between serum IGFBP-1 and attention in the TRS group (r = 0.411, p = 0.021), immediate memory in the CMS group (r = -0.417, p = 0.003), and RBANS total score in the CMS group (r = -0.368, p = 0.009). Multiple regression analysis adjusting for confounding factors revealed that serum IGFBP-1 was independently associated with attention in TRS patients (p = 0.016, 95 %CI. 0.002-0.015) and immediate memory in CMS patients (p = 0.022, 95 %CI-0.012 to -0.001). CONCLUSIONS Elevated serum IGFBP-1 concentration may serve as a predictive biomarker for distinct cognitive deficits in TRS and CMS patients. Further investigations are warranted.
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Affiliation(s)
- Haidong Yang
- Department of Psychiatry, The Fourth People's Hospital of Lianyungang, The Affiliated KangDa College of Nanjing Medical University, Lianyungang, 222003, China; Institute of Mental Health, Suzhou Psychiatric Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, 215137, China.
| | - Man Yang
- Department of Psychiatry, The Fourth People's Hospital of Lianyungang, The Affiliated KangDa College of Nanjing Medical University, Lianyungang, 222003, China.
| | - Yuting Zhang
- Department of Psychiatry, The Fourth People's Hospital of Lianyungang, The Affiliated KangDa College of Nanjing Medical University, Lianyungang, 222003, China.
| | - Zhihui Shi
- Department of Psychiatry, The Fourth People's Hospital of Lianyungang, The Affiliated KangDa College of Nanjing Medical University, Lianyungang, 222003, China.
| | - Xiaobin Zhang
- Institute of Mental Health, Suzhou Psychiatric Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, 215137, China.
| | - Caiyi Zhang
- Department of Psychiatry, The Second Medical College of Xuzhou Medical University, Xuzhou, 221004, China; Department of Psychiatry, The Affiliated Xuzhou Oriental Hospital of Xuzhou Medical University, Xuzhou, 221004, China.
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Adasheva DA, Serebryanaya DV. IGF Signaling in the Heart in Health and Disease. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:1402-1428. [PMID: 39245453 DOI: 10.1134/s0006297924080042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 06/11/2024] [Accepted: 06/22/2024] [Indexed: 09/10/2024]
Abstract
One of the most vital processes of the body is the cardiovascular system's proper operation. Physiological processes in the heart are regulated by the balance of cardioprotective and pathological mechanisms. The insulin-like growth factor system (IGF system, IGF signaling pathway) plays a pivotal role in regulating growth and development of various cells and tissues. In myocardium, the IGF system provides cardioprotective effects as well as participates in pathological processes. This review summarizes recent data on the role of IGF signaling in cardioprotection and pathogenesis of various cardiovascular diseases, as well as analyzes severity of these effects in various scenarios.
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Affiliation(s)
- Daria A Adasheva
- Department of Biochemistry, Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Daria V Serebryanaya
- Department of Biochemistry, Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia.
- Pirogov Russian National Research Medical University, Moscow, 117997, Russia
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Giraudi PJ, Laraño AA, Monego SD, Pravisani R, Bonazza D, Gondolesi G, Tiribelli C, Baralle F, Baccarani U, Licastro D. Genome-wide DNA methylation and transcriptomic analysis of liver tissues subjected to early ischemia/reperfusion injury upon human liver transplantation. Ann Hepatol 2024; 29:101506. [PMID: 38710471 DOI: 10.1016/j.aohep.2024.101506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 03/11/2024] [Accepted: 03/27/2024] [Indexed: 05/08/2024]
Abstract
INTRODUCTION AND OBJECTIVES Epigenetic changes represent a mechanism connecting external stresses with long-term modifications of gene expression programs. In solid organ transplantation, ischemia-reperfusion injury (IRI) appears to induce epigenomic changes in the graft, although the currently available data are extremely limited. The present study aimed to characterize variations in DNA methylation and their effects on the transcriptome in liver transplantation from brain-dead donors. PATIENTS AND METHODS 12 liver grafts were evaluated through serial biopsies at different timings in the procurement-transplantation process: T0 (warm procurement, in donor), T1 (bench surgery), and T2 (after reperfusion, in recipient). DNA methylation (DNAm) and transcriptome profiles of biopsies were analyzed using microarrays and RNAseq. RESULTS Significant variations in DNAm were identified, particularly between T2 and T0. Functional enrichment of the best 1000 ranked differentially methylated promoters demonstrated that 387 hypermethylated and 613 hypomethylated promoters were involved in spliceosomal assembly and response to biotic stimuli, and inflammatory immune responses, respectively. At the transcriptome level, T2 vs. T0 showed an upregulation of 337 and downregulation of 61 genes, collectively involved in TNF-α, NFKB, and interleukin signaling. Cell enrichment analysis individuates macrophages, monocytes, and neutrophils as the most significant tissue-cell type in the response. CONCLUSIONS In the process of liver graft procurement-transplantation, IRI induces significant epigenetic changes that primarily act on the signaling pathways of inflammatory responses dependent on TNF-α, NFKB, and interleukins. Our DNAm datasets are the early IRI methylome literature and will serve as a launch point for studying the impact of epigenetic modification in IRI.
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Affiliation(s)
- Pablo J Giraudi
- Metabolic Liver Disease Unit, Fondazione Italiana Fegato, Trieste, Italy.
| | - Allen A Laraño
- Metabolic Liver Disease Unit, Fondazione Italiana Fegato, Trieste, Italy; Research Institute for Tropical Medicine, Department of Health, Muntinlupa City, Philippines
| | | | - Riccardo Pravisani
- Liver-Kidney Transplant Unit, Department of Medicine, University of Udine, Italy
| | - Deborah Bonazza
- Anatomia ed Istologia Patologica, Cattinara Hospital, ASUGI, Trieste, Italy
| | - Gabriel Gondolesi
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería, Universidad Favaloro, Buenos Aires, Argentina
| | - Claudio Tiribelli
- Metabolic Liver Disease Unit, Fondazione Italiana Fegato, Trieste, Italy
| | - Francisco Baralle
- Metabolic Liver Disease Unit, Fondazione Italiana Fegato, Trieste, Italy
| | - Umberto Baccarani
- Liver-Kidney Transplant Unit, Department of Medicine, University of Udine, Italy
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Salatino A, Mirabelli M, Chiefari E, Greco M, Di Vito A, Bonapace G, Brunetti FS, Crocerossa F, Epstein AL, Foti DP, Brunetti A. The anticancer effects of Metformin in the male germ tumor SEM-1 cell line are mediated by HMGA1. Front Endocrinol (Lausanne) 2022; 13:1051988. [PMID: 36506071 PMCID: PMC9727077 DOI: 10.3389/fendo.2022.1051988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 11/09/2022] [Indexed: 11/24/2022] Open
Abstract
INTRODUCTION Germ cell tumors (GCTs) are the most common type of cancer in young men. These tumors usually originate from the testis, but they can occasionally develop from extragonadal sites probably due to primordial germ cells (PGCs) migration errors. Cisplatin-based chemotherapy is usually effective for male GCTs, but the risk of toxicity is high and new therapeutic strategies are needed. Although Metformin (Met) has been widely studied as a potential cancer treatment over the past decades, there is limited evidence to support its use in treating male GCTs. Additionally, the mechanism by which it acts on tumor cells is still not entirely understood. METHODS SEM-1 cells, a newly established human cell line of extragonadal origin, were treated with Met. Cell viability was studied by MTT assay, while cell migration and invasion were studied by the wound healing assay and the transwell assay, respectively. The effect of Met on 3D spheroid formation was determined by seeding SEM-1 cells in appropriate cell suspension culture conditions, and cell cycle was characterized by flow cytometry. Factors involved in PGCs migration and GCT invasion, such as IGFBP1, IGF1R, MMP-11 and c-Kit, together with cyclin D1 (a key regulator of cell cycle progression), and the upstream factor, HMGA1, were determined by immunoblots. RESULTS Treatment of SEM-1 cells with Met resulted in a potent and dose-dependent reduction of cell proliferation, as evidenced by decreased nuclear abundance of cyclin D1 and cell cycle arrest in G1 phase. Also, Met prevented the formation of 3D spheroids, and blocked cell migration and invasion by reducing the expression of IGFBP1, IGF1R and MMP-11. Both, IGFBP1 and MMP-11 are under control of HMGA1, a chromatin-associated protein that is involved in the regulation of important oncogenic, metabolic and embryological processes. Intriguingly, an early reduction in the nuclear abundance of HMGA1 occurred in SEM-1 cells treated with Met. CONCLUSIONS Our results document the antiproliferative and antimigratory effects of Met in SEM-1 cells, providing new insights into the potential treatments for male GCTs. The anticancer properties of Met in SEM-1 cells are likely related to its ability to interfere with HMGA1 and downstream targets, including cyclin D1, the IGFs system, and MMP-11.
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Affiliation(s)
- Alessandro Salatino
- Department of Health Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Maria Mirabelli
- Department of Health Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Eusebio Chiefari
- Department of Health Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Marta Greco
- Department of Health Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Anna Di Vito
- Department of Experimental and Clinical Medicine, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Giuseppe Bonapace
- Department of Medical and Surgical Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Francesco S. Brunetti
- Department of Health Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Fabio Crocerossa
- Department of Experimental and Clinical Medicine, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Alan L. Epstein
- Department of Pathology, USC Keck School of Medicine, Los Angeles, CA, United States
| | - Daniela P. Foti
- Department of Experimental and Clinical Medicine, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
| | - Antonio Brunetti
- Department of Health Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
- *Correspondence: Antonio Brunetti,
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Transcriptome analysis provides the first insight into the molecular basis of temperature plasticity in Banggai cardinalfish, Pterapogon kauderni. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART D, GENOMICS & PROTEOMICS 2021; 40:100909. [PMID: 34479169 DOI: 10.1016/j.cbd.2021.100909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/22/2021] [Accepted: 08/22/2021] [Indexed: 01/11/2023]
Abstract
Banggai cardinalfish, Pterapogon kauderni, is a tropical fish listed as an endangered species by IUCN. Its distribution and survival condition are extremely limited, and the changes of living environment caused by global warming may seriously threaten its geographical distribution. In order to understand the survival temperature range and the potential mechanism of temperature plasticity of P. kauderni, transcriptome analysis was performed under five temperature conditions (18 °C, 22 °C, 26 °C, 30 °C and 34 °C). A total of 432,444,497 clean reads were obtained from the mix tissues of whole head, viscera (except intestine), and muscle. All clean data were spliced into 194,832 unigenes. Compared with 26 °C, 57, 107, 187 and 174 differentially expressed genes (DEGs) were obtained at 18 °C, 22 °C, 30 °C and 34 °C, respectively. Gene Ontology (GO) analysis showed the most highly enriched in the DEGs were cellular processes, binding, metabolic processes and biological regulation. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated circadian rhythm, protein processing in endoplasmic reticulum, influenza A and prion disease were significantly enriched. 47 genes that may be related to temperature stress were identified, such as Per1, MLP, IGFBP1, HSP70, HSP90α, HSPA4, DNAJB1, CALR. This is the first RNA-Seq study of P. kauderni. This information should be valuable for further targeted studies on temperature tolerance, thereby assisting the protection and development of P. kauderni.
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Lin YW, Weng XF, Huang BL, Guo HP, Xu YW, Peng YH. IGFBP-1 in cancer: expression, molecular mechanisms, and potential clinical implications. Am J Transl Res 2021; 13:813-832. [PMID: 33841624 PMCID: PMC8014352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 12/09/2020] [Indexed: 02/05/2023]
Abstract
Insulin-like growth factor binding protein-1 (IGFBP-1) belongs to the insulin-like growth factor (IGF) system, which plays an indispensable role in normal growth and development, and in the pathophysiology of various tumors. IGFBP-1 has been shown to be associated with the risk of various tumors, and has a vital function in regulating tumor behaviors such as proliferation, migration, invasion and adhesion through different molecular mechanisms. The biological actions of IGFBP-1 in cancer are found to be related to its phosphorylation state, and the IGF-dependent and -independent mechanisms. In this review, we provided an overview of IGFBP-1 in normal physiology, and its aberrantly expression and the underlying molecular mechanisms in a range of common tumors, as well as discussed the potential clinical implications of IGFBP-1 as diagnostic or prognostic biomarkers in cancer.
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Affiliation(s)
- Yi-Wei Lin
- Department of Clinical Laboratory Medicine, The Cancer Hospital of Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
- Precision Medicine Research Center, Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
| | - Xue-Fen Weng
- Department of Clinical Laboratory Medicine, The Cancer Hospital of Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
- Precision Medicine Research Center, Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
| | - Bin-Liang Huang
- Department of Clinical Laboratory Medicine, The Cancer Hospital of Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
- Precision Medicine Research Center, Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
| | - Hai-Peng Guo
- Department of Head and Neck Surgery, The Cancer Hospital of Shantou University Medical CollegeShantou 515041, People’s Republic of China
| | - Yi-Wei Xu
- Department of Clinical Laboratory Medicine, The Cancer Hospital of Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
- Precision Medicine Research Center, Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
| | - Yu-Hui Peng
- Department of Clinical Laboratory Medicine, The Cancer Hospital of Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
- Precision Medicine Research Center, Shantou University Medical CollegeShantou, Guangdong, People’s Republic of China
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Boughanem H, Yubero-Serrano EM, López-Miranda J, Tinahones FJ, Macias-Gonzalez M. Potential Role of Insulin Growth-Factor-Binding Protein 2 as Therapeutic Target for Obesity-Related Insulin Resistance. Int J Mol Sci 2021; 22:ijms22031133. [PMID: 33498859 PMCID: PMC7865532 DOI: 10.3390/ijms22031133] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/13/2021] [Accepted: 01/21/2021] [Indexed: 12/26/2022] Open
Abstract
Evidence from observational and in vitro studies suggests that insulin growth-factor-binding protein type 2 (IGFBP2) is a promising protein in non-communicable diseases, such as obesity, insulin resistance, metabolic syndrome, or type 2 diabetes. Accordingly, great efforts have been carried out to explore the role of IGFBP2 in obesity state and insulin-related diseases, which it is typically found decreased. However, the physiological pathways have not been explored yet, and the relevance of IGFBP2 as an important pathway integrator of metabolic disorders is still unknown. Here, we review and discuss the molecular structure of IGFBP2 as the first element of regulating the expression of IGFBP2. We highlight an update of the association between low serum IGFBP2 and an increased risk of obesity, type 2 diabetes, metabolic syndrome, and low insulin sensitivity. We hypothesize mechanisms of IGFBP2 on the development of obesity and insulin resistance in an insulin-independent manner, which meant that could be evaluated as a therapeutic target. Finally, we cover the most interesting lifestyle modifications that regulate IGFBP2, since lifestyle factors (diet and/or physical activity) are associated with important variations in serum IGFBP2.
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Affiliation(s)
- Hatim Boughanem
- Department of Endocrinology and Nutrition, Institute of Biomedical Research Institute in Malaga (IBIMA), Virgen de la Victoria University Hospital, 29010 Málaga, Spain;
| | - Elena M. Yubero-Serrano
- Lipids and Atherosclerosis Unit, Maimonides Institute for Biomedical Research in Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004 Córdoba, Spain; (E.M.Y.-S.); (J.L.-M.)
- CIBEROBN (CIBER in Physiopathology of Obesity and Nutrition), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - José López-Miranda
- Lipids and Atherosclerosis Unit, Maimonides Institute for Biomedical Research in Cordoba (IMIBIC), Reina Sofia University Hospital, University of Córdoba, 14004 Córdoba, Spain; (E.M.Y.-S.); (J.L.-M.)
- CIBEROBN (CIBER in Physiopathology of Obesity and Nutrition), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Francisco J. Tinahones
- Department of Endocrinology and Nutrition, Institute of Biomedical Research Institute in Malaga (IBIMA), Virgen de la Victoria University Hospital, 29010 Málaga, Spain;
- CIBEROBN (CIBER in Physiopathology of Obesity and Nutrition), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Correspondence: (F.J.T.); (M.M.-G.); Tel.: +34-951-036-2647 (F.J.T. & M.M.-G.); Fax: +34-951-924-651 (F.J.T. & M.M.-G.)
| | - Manuel Macias-Gonzalez
- Department of Endocrinology and Nutrition, Institute of Biomedical Research Institute in Malaga (IBIMA), Virgen de la Victoria University Hospital, 29010 Málaga, Spain;
- CIBEROBN (CIBER in Physiopathology of Obesity and Nutrition), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Correspondence: (F.J.T.); (M.M.-G.); Tel.: +34-951-036-2647 (F.J.T. & M.M.-G.); Fax: +34-951-924-651 (F.J.T. & M.M.-G.)
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Yen TJ, Lolicato M, Thomas-Tran R, Du Bois J, Minor DL. Structure of the saxiphilin:saxitoxin (STX) complex reveals a convergent molecular recognition strategy for paralytic toxins. SCIENCE ADVANCES 2019; 5:eaax2650. [PMID: 31223657 PMCID: PMC6584486 DOI: 10.1126/sciadv.aax2650] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 05/13/2019] [Indexed: 05/13/2023]
Abstract
Dinoflagelates and cyanobacteria produce saxitoxin (STX), a lethal bis-guanidinium neurotoxin causing paralytic shellfish poisoning. A number of metazoans have soluble STX-binding proteins that may prevent STX intoxication. However, their STX molecular recognition mechanisms remain unknown. Here, we present structures of saxiphilin (Sxph), a bullfrog high-affinity STX-binding protein, alone and bound to STX. The structures reveal a novel high-affinity STX-binding site built from a "proto-pocket" on a transferrin scaffold that also bears thyroglobulin domain protease inhibitor repeats. Comparison of Sxph and voltage-gated sodium channel STX-binding sites reveals a convergent toxin recognition strategy comprising a largely rigid binding site where acidic side chains and a cation-π interaction engage STX. These studies reveal molecular rules for STX recognition, outline how a toxin-binding site can be built on a naïve scaffold, and open a path to developing protein sensors for environmental STX monitoring and new biologics for STX intoxication mitigation.
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Affiliation(s)
- Tien-Jui Yen
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Marco Lolicato
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94158, USA
| | | | - J. Du Bois
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Daniel L. Minor
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94158, USA
- Departments of Biochemistry and Biophysics, and Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
- California Institute for Quantitative Biomedical Research, San Francisco, CA 94158, USA
- Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA 94158, USA
- Molecular Biophysics and Integrated Bio-imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Corresponding author.
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Žuvela P, Macur K, Jay Liu J, Bączek T. Exploiting non-linear relationships between retention time and molecular structure of peptides originating from proteomes and comparing three multivariate approaches. J Pharm Biomed Anal 2016; 127:94-100. [DOI: 10.1016/j.jpba.2016.01.055] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 01/11/2016] [Accepted: 01/23/2016] [Indexed: 12/21/2022]
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Žuvela P, Liu JJ, Macur K, Bączek T. Molecular Descriptor Subset Selection in Theoretical Peptide Quantitative Structure–Retention Relationship Model Development Using Nature-Inspired Optimization Algorithms. Anal Chem 2015; 87:9876-83. [DOI: 10.1021/acs.analchem.5b02349] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Petar Žuvela
- Department
of Chemical Engineering, Pukyong National University, 365 Sinseon-ro, 608-739 Busan, Korea
| | - J. Jay Liu
- Department
of Chemical Engineering, Pukyong National University, 365 Sinseon-ro, 608-739 Busan, Korea
| | - Katarzyna Macur
- Laboratory
of Mass Spectrometry, Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Kładki
24, 80-822 Gdańsk, Poland
| | - Tomasz Bączek
- Department
of Pharmaceutical Chemistry, Medical University of Gdańsk, Hallera
107, 80-416 Gdańsk, Poland
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Brandt K, Grünler J, Brismar K, Wang J. Effects of IGFBP-1 and IGFBP-2 and their fragments on migration and IGF-induced proliferation of human dermal fibroblasts. Growth Horm IGF Res 2015; 25:34-40. [PMID: 25468444 DOI: 10.1016/j.ghir.2014.11.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 09/22/2014] [Accepted: 11/02/2014] [Indexed: 01/13/2023]
Abstract
OBJECTIVE A family of six insulin-like growth factor (IGF) binding-proteins (IGFBP) bind to IGF-I and IGF-II with high affinity and modulate their activity. We have recently shown that a neutrophil-derived protease activity cleaved IGFBP-1, -2 and -4. IGFBP-1 and IGFBP-2 have a C-terminal Arg-Gly-Asp (RGD) sequence, and IGFBP-1 has been shown by others to stimulate migration through binding of its RGD sequence to α5β1 integrin. The aim of this study was to determine the effect of this IGFBP protease on IGF-induced proliferation and the effect of IGFBP-1 and IGFBP-2 and their proteolytic fragments on migration in normal and high glucose of human dermal fibroblasts (HDF). DESIGN We investigated the effect of intact or cleaved IGFBP-1 and -2 on proliferation in cultured HDFs and on HDF migration in normal and high glucose. RESULTS Both IGFBP-1 and IGFBP-2 and their proteolytic fragments stimulated HDF migration and the stimulatory effect was abolished by pre-treating cells with a α5β1 integrin antibody. High glucose impaired migration of HDFs; however, the addition of IGFBP-1, IGFBP-2 or fragments increased migration to levels observed in normoglycemia. IGFBP-2 inhibited IGF-II induced proliferation; however, the inhibitory effect was reduced after being cleaved. Intact native IGFBP-1 showed either potentiating or inhibitory effects on IGF-I induced proliferation depending on the confluence of cells, and proteolysis of IGFBP-1 did not change these effects. IGFBP-1 was found to increase phosphorylation of FAK and ERK1/2 and this effect was inhibited by the monoclonal integrin a5β1 ab. CONCLUSIONS IGFBP-1 and -2 and their proteolytic fragments may improve tissue repair under inflammatory conditions, through effects on proliferation and migration of HDFs in normal and high glucose.
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Affiliation(s)
- Katrin Brandt
- Department of Molecular Medicine and Surgery, Karolinska Institute, Department of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital, Stockholm, Sweden
| | - Jacob Grünler
- Department of Molecular Medicine and Surgery, Karolinska Institute, Department of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital, Stockholm, Sweden.
| | - Kerstin Brismar
- Department of Molecular Medicine and Surgery, Karolinska Institute, Department of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital, Stockholm, Sweden
| | - Jing Wang
- Department of Molecular Medicine and Surgery, Karolinska Institute, Department of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital, Stockholm, Sweden
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Zhang S, Zhao Y, Hu X, Liu Z, Chen X, Chen X, Du J. Distinct post-transcriptional regulation of Igfbp1 gene by hypoxia in lowland mouse and Qinghai-Tibet plateau root vole Microtus oeconomus. Mol Cell Endocrinol 2013; 376:33-42. [PMID: 23748030 DOI: 10.1016/j.mce.2013.05.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Revised: 05/28/2013] [Accepted: 05/31/2013] [Indexed: 12/11/2022]
Abstract
Our previous study revealed the particular expression patterns of insulin-like growth factor 1 (IGF1) and insulin-like growth factor binding protein 1 (IGFBP1) in the Qinghai-Tibet plateau root vole (Microtus oeconomus) under hypoxic challenge. Here we report the molecular mechanisms of Igf gene regulation associated with adaptation to hypoxia. M. oeconomus IGF1 and IGFBP1 were shown to be highly conserved. Hypoxia (8.0% O2, 6h) did not change the liver-derived Igf1 expression in either M. oeconomus or mouse. Hypoxia significantly upregulated hepatic Igfbp1 gene expression and IGFBP1 levels in the liver and plasma of the mouse, but not in M. oeconomus. A functional U-rich element in the 3' untranslated region was found in mouse Igfbp1 mRNA, which was associated with Igfbp1 mRNA stabilization and upregulation under hypoxia, and this U-rich element was eliminated in the M. oeconomus Igfbp1, resulting in blunted Igfbp1 mRNA upregulation, which might be understood as a sequence variation modified during molecular evolution under hypoxia.
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Affiliation(s)
- Shengting Zhang
- Division of Neurobiology and Physiology, Department of Basic Medical Sciences, School of Medicine, Zhejiang University, Hangzhou, China.
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Abu Shehab M, Iosef C, Wildgruber R, Sardana G, Gupta MB. Phosphorylation of IGFBP-1 at discrete sites elicits variable effects on IGF-I receptor autophosphorylation. Endocrinology 2013; 154:1130-43. [PMID: 23354097 DOI: 10.1210/en.2012-1962] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We previously demonstrated that hypoxia and leucine deprivation cause hyperphosphorylation of IGF-binding protein-1 (IGFBP-1) at discrete sites that markedly enhanced IGF-I affinity and inhibited IGF-I-stimulated cell growth. In this study we investigated the functional role of these phosphorylation sites using mutagenesis. We created three IGFBP-1 mutants in which individual serine (S119/S169/S98) residues were substituted with alanine and S101A was recreated for comparison. The wild-type (WT) and mutant IGFBP-1 were expressed in Chinese hamster ovary cells and IGFBP-1 in cell media was isolated using isoelectric-focusing-free-flow electrophoresis. BIACore analysis indicated that the changes in IGF-I affinity for S98A and S169A were moderate, whereas S119A greatly reduced the affinity of IGFBP-1 for IGF-I (100-fold, P < .0001). Similar results were obtained with S101A. The IGF-I affinity changes of the mutants were reflected in their ability to inhibit IGF-I-induced receptor autophosphorylation. Employing receptor-stimulation assay using IGF-IR-overexpressing P6 cells, we found that WT-IGFBP-1 inhibited IGF-IRβ autophosphorylation (~2-fold, P < .001), possibly attributable to sequestration of IGF-I. Relative to WT, S98A and S169A mutants did not inhibit receptor autophosphorylation. S119A, on the other hand, greatly stimulated the receptor (2.3-fold, P < .05). The data with S101A matched S119A. In summary, we show that phosphorylation at S98 and S169 resulted in milder changes in IGF-I action; nonetheless most dramatic inhibitory effects on the biological activity of IGF-I were due to IGFBP-1 phosphorylation at S119. Our results provide novel demonstration that IGFBP-1 phosphorylation at S119 can enhance affinity for IGF-I possibly through stabilization of the IGF-IGFBP-1 complex. These data also propose that the synergistic interaction of distinct phosphorylation sites may be important in eliciting more pronounced effects on IGF-I affinity that needs further investigation.
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Forbes BE, McCarthy P, Norton RS. Insulin-like growth factor binding proteins: a structural perspective. Front Endocrinol (Lausanne) 2012; 3:38. [PMID: 22654863 PMCID: PMC3356058 DOI: 10.3389/fendo.2012.00038] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 02/16/2012] [Indexed: 11/13/2022] Open
Abstract
Insulin-like growth factor binding proteins (IGFBP-1 to -6) bind insulin-like growth factors-I and -II (IGF-I and IGF-II) with high affinity. These binding proteins maintain IGFs in the circulation and direct them to target tissues, where they promote cell growth, proliferation, differentiation, and survival via the type 1 IGF receptor. IGFBPs also interact with many other molecules, which not only influence their modulation of IGF action but also mediate IGF-independent activities that regulate processes such as cell migration and apoptosis by modulating gene transcription. IGFBPs-1 to -6 are structurally similar proteins consisting of three distinct domains, N-terminal, linker, and C-terminal. There have been major advances in our understanding of IGFBP structure in the last decade and a half. While there is still no structure of an intact IGFBP, several structures of individual N- and C-domains have been solved. The structure of a complex of N-BP-4:IGF-I:C-BP-4 has also been solved, providing a detailed picture of the structural features of the IGF binding site and the mechanism of binding. Structural studies have also identified features important for interaction with extracellular matrix components and integrins. This review summarizes structural studies reported so far and highlights features important for binding not only IGF but also other partners. We also highlight future directions in which structural studies will add to our knowledge of the role played by the IGFBP family in normal growth and development, as well as in disease.
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Affiliation(s)
- Briony E Forbes
- The School of Molecular and Biomedical Science, The University of Adelaide Adelaide, SA, Australia
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15
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Nili M, Mukherjee A, Shinde U, David L, Rotwein P. Defining the disulfide bonds of insulin-like growth factor-binding protein-5 by tandem mass spectrometry with electron transfer dissociation and collision-induced dissociation. J Biol Chem 2011; 287:1510-9. [PMID: 22117064 DOI: 10.1074/jbc.m111.285528] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The six high-affinity insulin-like growth factor-binding proteins (IGFBPs) comprise a conserved family of secreted molecules that modulate IGF actions by regulating their half-life and access to signaling receptors, and also exert biological effects that are independent of IGF binding. IGFBPs are composed of cysteine-rich amino- (N-) and carboxyl- (C-) terminal domains, along with a cysteine-poor central linker segment. IGFBP-5 is the most conserved IGFBP, and contains 18 cysteines, but only 2 of 9 putative disulfide bonds have been mapped to date. Using a mass spectrometry (MS)-based strategy combining sequential electron transfer dissociation (ETD) and collision-induced dissociation (CID) steps, in which ETD fragmentation preferentially induces cleavage of disulfide bonds, and CID provides exact disulfide linkage assignments between liberated peptides, we now have definitively mapped 5 disulfide bonds in IGFBP-5. In addition, in conjunction with ab initio molecular modeling we are able to assign the other 4 disulfide linkages to within a GCGCCXXC motif that is conserved in five IGFBPs. Because of the nature of ETD fragmentation MS experiments were performed without chemical reduction of IGFBP-5. Our results not only establish a disulfide bond map of IGFBP-5 but also define a general approach that takes advantage of the specificity of ETD and the scalability of tandem MS, and the predictive power of ab initio molecular modeling to characterize unknown disulfide linkages in proteins.
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Affiliation(s)
- Mahta Nili
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon 97239-3098, USA
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Pavšič M, Lenarčič B. Expression, crystallization and preliminary X-ray characterization of the human epithelial cell-adhesion molecule ectodomain. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:1363-6. [PMID: 22102232 DOI: 10.1107/s1744309111031897] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 08/06/2011] [Indexed: 11/10/2022]
Abstract
The epithelial cell-adhesion molecule (EpCAM; CD326) is a transmembrane glycoprotein involved in epithelial cell-cell adhesion, cell proliferation and differentiation. Its elevated expression level in various carcinomas is exploited by several antitumour therapies that are at various stages of clinical development. The 35 kDa polypeptide chain of EpCAM is divided into a large extracellular part, a transmembrane helix and a short cytoplasmic tail. The modular extracellular part of human EpCAM was cloned and mutated to prevent N-linked glycosylation. After expression in insect cells and purification using standard chromatographic techniques, the extracellular part was crystallized. The crystals belonged to space group C2, with unit-cell parameters a = 86.83, b = 50.16, c = 66.56 Å, β = 127.9°. The crystal diffracted to 1.95 Å resolution and contained one molecule in the asymmetric unit.
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Affiliation(s)
- Miha Pavšič
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana, Slovenia
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17
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Macur K, Temporini C, Massolini G, Grzenkowicz-Wydra J, Obuchowski M, Bączek T. Proteomic analysis of small acid soluble proteins in the spore core of Bacillus subtilis ΔprpE and 168 strains with predictions of peptides liquid chromatography retention times as an additional tool in protein identification. Proteome Sci 2010; 8:60. [PMID: 21092197 PMCID: PMC3003637 DOI: 10.1186/1477-5956-8-60] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Accepted: 11/22/2010] [Indexed: 12/03/2022] Open
Abstract
Background Sporulation, characteristic for some bacteria such as Bacillus subtilis, has not been entirely defined yet. Protein phosphatase E (PrpE) and small, acid soluble spore proteins (SASPs) influence this process. Nevertheless, direct result of PrpE interaction on SASPs content in spore coat of B. subtilis has not been evidenced so far. As proteomic approach enables global analysis of occurring proteins, therefore it was chosen in this experiment to compare SASPs occurrence in two strains of B. subtilis, standard 168 and ΔprpE, lacking PrpE phosphatase. Proteomic analysis is still a challenge, and despite of big approach in mass spectrometry (MS) field, the identification reliability remains unsatisfactory. Therefore there is a rising interest in new methods, particularly bioinformatic tools that would harden protein identification. Most of currently applied algorithms are based on MS-data. Information from separation steps is not still in routine usage, even though they also provide valuable facts about analyzed structures. The aim of this research was to apply a model for peptides retention times prediction, based on quantitative structure-retention relationships (QSRR) in SASPs analysis, obtained from two strains of B. subtilis proteome digests after separation and identification of the peptides by LC-ESI-MS/MS. The QSRR approach was applied as the additional constraint in proteomic research verifying results of MS/MS ion search and confirming the correctness of the peptides identifications along with the indication of the potential false positives and false negatives. Results In both strains of B. subtilis, peptides characteristic for SASPs were found, however their identification confidence varied. According to the MS identity parameter Xcorr and difference between predicted and experimental retention times (ΔtR) four groups could be distinguished: correctly and incorrectly identified, potential false positives and false negatives. The ΔprpE strain was characterized by much higher amount of SASPs peptides than standard 168 and their identification confidence was, mostly for alpha- and beta-type SASP, satisfactory. Conclusions The QSRR-based model for predicting retention times of the peptides, was a useful additional to MS tool, enhancing protein identification. Higher content of SASPs in strain lacking PrpE phosphatase suggests that this enzyme may influence their occurrence in the spores, lowering levels of these proteins.
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Affiliation(s)
- Katarzyna Macur
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, Hallera 107, 80-416 Gdańsk, Poland.
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Rosenzweig SA, Atreya HS. Defining the pathway to insulin-like growth factor system targeting in cancer. Biochem Pharmacol 2010; 80:1115-24. [PMID: 20599789 DOI: 10.1016/j.bcp.2010.06.013] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 06/12/2010] [Accepted: 06/15/2010] [Indexed: 12/28/2022]
Abstract
The insulin-like growth factors (IGFs; IGF-1 and IGF-2) play central roles in cell growth, differentiation, survival, transformation and metastasis. The biologic effects of the IGFs are mediated by the IGF-1 receptor (IGF-1R), a receptor tyrosine kinase with homology to the insulin receptor (IR). Dysregulation of the IGF system is well recognized as a key contributor to the progression of multiple cancers, with IGF-1R activation increasing the tumorigenic potential of breast, prostate, lung, colon and head and neck squamous cell carcinoma (HNSCC). Despite this relationship, targeting the IGF-1R has only recently undergone development as a molecular cancer therapeutic. As it has taken hold, we are witnessing a robust increase and interest in targeting the inhibition of IGF-1R signaling. This is accentuated by the list of over 30 drugs, including monoclonal antibodies (mAbs) and tyrosine kinase inhibitors (TKIs) that are under evaluation as single agents or in combination therapies. The IGF-binding proteins (IGFBPs) represent the third component of the IGF system consisting of a class of six soluble secretory proteins. They represent a unique class of naturally occurring IGF-antagonists that bind to and sequester IGF-1 and IGF-2, inhibiting their access to the IGF-1R. Due to their dual targeting of the IGFs without affecting insulin action, the IGFBPs are an untapped "third" class of IGF-1R inhibitors. In this commentary, we highlight some of the significant aspects of and prospects for targeting the IGF-1R and describe what the future may hold.
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Affiliation(s)
- Steven A Rosenzweig
- Department of Cell and Molecular Pharmacology & Experimental Therapeutics and Hollings Cancer Center, Medical University of South Carolina, 173 Ashley Avenue, PO Box 250505, Charleston, SC 29425-5050, USA.
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Correctness of protein identifications of Bacillus subtilis proteome with the indication on potential false positive peptides supported by predictions of their retention times. J Biomed Biotechnol 2009; 2010:718142. [PMID: 20069061 PMCID: PMC2801521 DOI: 10.1155/2010/718142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 09/24/2009] [Indexed: 01/11/2023] Open
Abstract
The predictive capability of the retention time prediction model based on quantitative structure-retention relationships (QSRR) was tested. QSRR model was derived with the use of set of peptides identified with the highest scores and originated from 8 known proteins annotated as model ones. The predictive ability of the QSRR model was verified with the use of a Bacillus subtilis proteome digest after separation and identification of the peptides by LC-ESI-MS/MS. That ability was tested with three sets of testing peptides assigned to the proteins identified with different levels of confidence. First, the set of peptides identified with the highest scores achieved in the search were considered. Hence, proteins identified on the basis of more than one peptide were taken into account. Furthermore, proteins identified on the basis of just one peptide were also considered and, depending on the possessed scores, both above and below the assumed threshold, were analyzed in two separated sets. The QSRR approach was applied as the additional constraint in proteomic research verifying results of MS/MS ion search and confirming the correctness of the peptides identifications along with the indication of the potential false positives.
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20
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Brandt K, Wang J, Lundell K, Ståhlberg M, Horn HV, Ehrenborg E, Hall K, Jörnvall H, Lewitt M. IGFBP-1 protease activity and IGFBP-1 fragments in a patient with multiple myeloma. Growth Horm IGF Res 2009; 19:507-512. [PMID: 19539506 DOI: 10.1016/j.ghir.2009.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2008] [Revised: 05/07/2009] [Accepted: 05/19/2009] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Cleavage of IGFBPs by proteases results in IGFBP fragments that have altered IGF-binding affinity, and IGF-independent roles. We have previously purified a specific IGFBP-1 protease activity from the urine of an individual with multiple myeloma and dermatitis. The aim of this study was to determine whether IGFBP-1 protease activity and/or IGFBP-1 fragments were present in the circulation of this patient. METHODS The size of immunoreactive IGFBP-1 in serum samples was determined after Superose 12 chromatography. Intact IGFBP-1 and IGFBP-1 fragments were characterized in four RIAs and after SDS-PAGE. RESULTS Specific proteolysis of IGFBP-1 generated an N-terminal fragment (IGFBP-1(1-130)) with a predicted molecular mass of 13kDa but an apparent mass of 21kDa on SDS-PAGE. A C-terminal fragment (IGFBP-1(131-234)) produced in vitro migrated at 11.4kDa, close to its predicted size. However a C-terminal fragment of cleaved IGFBP-1 (IGFBP-1(142-234)) migrated at 14kDa on SDS-PAGE. Serum from the patient inhibited IGFBP-1 protease activity. Immunoreactive IGFBP-1 in patient serum was present at molecular masses consistent with IGFBP-1 fragments, in addition to intact IGFBP-1. CONCLUSIONS Specific cleavage of IGFBP-1 occurs at the tissue level and not in the circulation in a patient with multiple myeloma and dermatitis. The fragments that are generated may have endocrine roles.
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Affiliation(s)
- Katrin Brandt
- Department of Molecular Medicine and Surgery, Karolinska Institutet, L1:01 Karolinska University Hospital Solna, SE-171 76 Stockholm, Sweden
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21
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Dolcini L, Sala A, Campagnoli M, Labò S, Valli M, Visai L, Minchiotti L, Monaco HL, Galliano M. Identification of the amniotic fluid insulin-like growth factor binding protein-1 phosphorylation sites and propensity to proteolysis of the isoforms. FEBS J 2009; 276:6033-46. [PMID: 19765076 DOI: 10.1111/j.1742-4658.2009.07318.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Insulin-like growth factor binding protein-1 (IGFBP-1) is the major secreted protein of human decidual cells during gestation and, as a modulator of insulin-like growth factors or by independent mechanisms, regulates embryonic implantation and growth. The protein is phosphorylated and this post-translational modification is regulated in pregnancy and represents an important determinant of its biological activity. We have isolated, from human normal amniotic fluid collected in the weeks 16-18, the intact nonphosphorylated IGFBP-1 and five electrophoretically distinct phosphoisoforms and have determined their in vivo phosphorylation state. The unmodified protein was the most abundant component and mono-, bi-, tri- and tetraphosphorylated forms were present in decreasing amounts. The phosphorylation sites of IGFBP-1 were identified by liquid chromatography-tandem mass spectrometry analysis of the peptides generated with trypsin, chymotrypsin and Staphylococcus aureus V8 protease. Five serines were found to be phosphorylated and, of these, four are localized in the central, weakly conserved, region, at positions 95, 98, 101 and 119, whereas one, Ser169, is in the C-terminal domain. The post-translational modification predominantly involves the hydrophilic stretch of amino acids representing a potential PEST sequence (proline, glutamic acid, serine, threonine) and our results show that the phosphorylation state influences the propensity of IGFBP-1 to proteolysis.
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Affiliation(s)
- Lorenzo Dolcini
- Department of Biochemistry 'A. Castellani', University of Pavia, Italy
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22
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Jogie-Brahim S, Feldman D, Oh Y. Unraveling insulin-like growth factor binding protein-3 actions in human disease. Endocr Rev 2009; 30:417-37. [PMID: 19477944 PMCID: PMC2819737 DOI: 10.1210/er.2008-0028] [Citation(s) in RCA: 230] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The IGF system plays critical roles in somatic growth in an endocrine fashion (somatomedin hypothesis) as well as proliferation and differentiation of normal and malignant cells in a paracrine/autocrine fashion. IGFBP-3 is known to modulate the actions of IGFs in circulation as well as the immediate extracellular environment. Interestingly, apart from the ability to inhibit or enhance IGF actions, IGFBP-3 also exhibits very clear, distinct biological effects independent of the IGF/IGF-I receptor axis. Over the past decade it has become widely appreciated that IGF/IGF-IR-independent actions of IGFBP-3 (antiproliferative and proapoptotic effects) contribute to improving the pathophysiology of a variety of human diseases, such as cancer, diabetes, and malnutrition. Recent studies have implicated interaction of IGFBP-3 with a variety of proteins or signaling cascades critical to cell cycle control and apoptosis; however, the actual mechanism of IGFBP-3 action is still unclear. This review reinforces the concept in support of the IGF/IGF-IR axis-independent actions of IGFBP-3 and delineates potential underlying mechanisms involved and subsequent biological significance, focusing in particular on functional binding partners and the clinical significance of IGFBP-3 in the assessment of cancer risk.
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Affiliation(s)
- Sherryline Jogie-Brahim
- Department of Pathology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, Virginia 23298-0662, USA
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23
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Temporini C, Calleri E, Cabrera K, Felix G, Massolini G. On-line multi-enzymatic approach for improved sequence coverage in protein analysis. J Sep Sci 2009; 32:1120-8. [PMID: 19301325 DOI: 10.1002/jssc.200800596] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The development of a new mixed bioreactor for proteomic studies based on trypsin and chymotrypsin is described. Trypsin and chymotrypsin were simultaneously bonded to an epoxy monolithic silica column (100 mmx4.6 mm id) in a one-step reaction via epoxy-groups. In order to compare the catalytic properties of the two enzymes in the isolated and in the multi-enzymatic approach, two other single enzyme bioreactors based on trypsin and chymotrypsin were prepared following the same immobilization protocol. The kinetic parameters of the multi-enzymatic bioreactor were derived and it was demonstrated that it retains the individual catalytic activity of the two enzymes. To prove the power of this experimental approach the new mixed bioreactor was integrated in an LC-ESI-MS/MS system for digestion, enrichment, separation and identification of the test protein insulin-like growth factor binding-protein 1 (IGFBP-1). The peptide map and protein sequence coverage obtained with the three bioreactors were compared. The results clearly indicate that the proposed multi-enzyme approach can reduce both digestion and analysis time, accelerate data interpretation and increase the confidence degree in protein identification.
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Affiliation(s)
- Caterina Temporini
- Department of Pharmaceutical Chemistry, University of Pavia, Pavia, Italy.
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24
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Wheatcroft SB, Kearney MT. IGF-dependent and IGF-independent actions of IGF-binding protein-1 and -2: implications for metabolic homeostasis. Trends Endocrinol Metab 2009; 20:153-62. [PMID: 19349193 DOI: 10.1016/j.tem.2009.01.002] [Citation(s) in RCA: 213] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Revised: 01/05/2009] [Accepted: 01/05/2009] [Indexed: 11/16/2022]
Abstract
Insulin-like growth factor (IGF)-binding proteins (IGFBPs) confer temporospatial regulation to IGF bioactivity. Both stimulatory and inhibitory effects of IGFBPs on IGF actions have been described, and IGF-independent effects of several IGFBPs are emerging. Accumulating evidence indicates important roles for members of the IGFBP family in metabolic homeostasis. For example, IGFBP-1 concentrations fluctuate inversely in response to changes in plasma insulin levels, implicating IGFBP-1 in glucoregulation, and fasting levels of IGFBP-1 predict insulin sensitivity at the population level. IGFBP-2 concentrations reflect long-term insulin sensitivity and are reduced in the presence of obesity. Here, we review the evolving roles of IGFBP-1 and IGFBP-2 in metabolic homeostasis, summarize their effects on IGF bioactivity and explore putative mechanisms by which they might exert IGF-independent cellular actions.
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Affiliation(s)
- Stephen B Wheatcroft
- Division of Cardiovascular & Diabetes Research, Leeds Institute of Genetics, Health & Therapeutics, University of Leeds, Leeds, UK
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25
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Nissum M, Abu Shehab M, Sukop U, Khosravi JM, Wildgruber R, Eckerskorn C, Han VKM, Gupta MB. Functional and complementary phosphorylation state attributes of human insulin-like growth factor-binding protein-1 (IGFBP-1) isoforms resolved by free flow electrophoresis. Mol Cell Proteomics 2009; 8:1424-35. [PMID: 19193607 DOI: 10.1074/mcp.m800571-mcp200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Fetal growth restriction (FGR) is a common disorder in which a fetus is unable to achieve its genetically determined potential size. High concentrations of insulin-like growth factor-binding protein-1 (IGFBP-1) have been associated with FGR. Phosphorylation of IGFBP-1 is a mechanism by which insulin-like growth factor-I (IGF-I) bioavailability can be modulated in FGR. In this study a novel strategy was designed to determine a link between IGF-I affinity and the concomitant phosphorylation state characteristics of IGFBP-1 phosphoisoforms. Using free flow electrophoresis (FFE), multiple IGFBP-1 phosphoisoforms in amniotic fluid were resolved within pH 4.43-5.09. The binding of IGFBP-1 for IGF-I in each FFE fraction was determined with BIAcore biosensor analysis. The IGF-I affinity (K(D)) for different IGFBP-1 isoforms ranged between 1.12e-08 and 4.59e-07. LC-MS/MS characterization revealed four phosphorylation sites, Ser(P)(98), Ser(P)(101), Ser(P)(119), and Ser(P)(169), of which Ser(P)(98) was new. Although the IGF-I binding affinity for IGFBP-1 phosphoisoforms across the FFE fractions did not correlate with phosphopeptide intensities for Ser(P)(101), Ser(P)(98), and Ser(P)(169) sites, a clear association was recorded with Ser(P)(119). Our data demonstrate that phosphorylation at Ser(119) plays a significant role in modulating affinity of IGFBP-1 for IGF-I. In addition, an altered profile of IGFBP-1 phosphoisoforms was revealed between FGR and healthy pregnancies that may result from potential site-specific phosphorylation. This study provides a strong basis for use of this novel approach in establishing the linkage between phosphorylation of IGFBP-1 and FGR. This overall strategy will also be broadly applicable to other phosphoproteins with clinical and functional significance.
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Affiliation(s)
- Mikkel Nissum
- BD Diagnostics, Am Klopferspitz 19a, 82152 Planegg, Germany
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26
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Rescue of Migratory Defects of Ehlers–Danlos Syndrome Fibroblasts In Vitro by Type V Collagen but not Insulin-Like Binding Protein-1. J Invest Dermatol 2008; 128:1915-9. [DOI: 10.1038/jid.2008.33] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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27
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Temporini C, Dolcini L, Abee A, Calleri E, Galliano M, Caccialanza G, Massolini G. Development of an integrated chromatographic system for on-line digestion and characterization of phosphorylated proteins. J Chromatogr A 2008; 1183:65-75. [PMID: 18255078 DOI: 10.1016/j.chroma.2007.12.091] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2007] [Revised: 11/29/2007] [Accepted: 12/31/2007] [Indexed: 10/22/2022]
Abstract
The development of an integrated chromatographic system for complete phosphoprotein analysis is described. The digestion of phosphoproteins with trypsin- or pronase-based monolithic bioreactors is carried out on-line with selective enrichment on a TiO(2) trap and separation of the produced phosphopeptides by reversed-phase liquid chromatography-multiple mass spectrometry (RPLC/MS(n)). A detailed study on the selective extraction of peptides with different degrees of phosphorylation on TiO(2) cartridges is discussed. This analytical strategy has been optimized using beta-casein as a standard phosphoprotein, and then applied to the identification of phosphorylation sites in insulin-like grow factor-binding protein 1 (IGFBP-1) isolated from amniotic fluid.
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Affiliation(s)
- C Temporini
- Dipartimento di Chimica Farmaceutica, Università di Pavia, Via Taramelli 12, Pavia, Italy.
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Graham ME, Kilby DM, Firth SM, Robinson PJ, Baxter RC. The in vivo phosphorylation and glycosylation of human insulin-like growth factor-binding protein-5. Mol Cell Proteomics 2007; 6:1392-405. [PMID: 17496250 DOI: 10.1074/mcp.m700027-mcp200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mass spectrometry is often used to determine post-translational modifications by analysis of tryptic digests of proteins. Here we demonstrate that the analysis of tryptic peptides together with analysis of the full-length protein provided optimal characterization of insulin-like growth factor-binding protein-5 (IGFBP-5) phosphorylation and glycosylation. IGFBP-5 binds insulin-like growth factors with high affinity and has important roles in cell survival, differentiation, and apoptosis. Until now, the primary structure of IGFBP-5 has been incompletely defined. We analyzed human IGFBP-5 from T47D cells by mass spectrometry to determine all of the in vivo post-translational modifications. In full-length IGFBP-5, 31% of the protein was unmodified, 37% was monophosphorylated, and 4% was diphosphorylated with no other modification. The remaining 27% was glycosylated, more than half of which was also monophosphorylated. The major phosphorylation site was Ser(96) in the central domain, and a minor phosphorylation site was Ser(248) near the C terminus. Neither site was phosphorylated in vitro by casein kinase 2, ruling it out as the in vivo kinase. An in vivo phosphorylation site was also found in IGFBP-2 at an analogous position, Ser(106). IGFBP-5 was heterogeneously O-glycosylated mainly by sialylated core 1 type glycans. The most abundant structure contained N-acetylhexosamine, hexose, and two N-acetylneuraminic acid carbohydrates. A small amount of sialylated core 2 type glycan was also present. Phosphorylation and O-glycosylation both affected IGFBP-5 binding to heparin but not insulin-like growth factor binding or ternary complex formation with the acid-labile subunit. The results reveal the first description of the in vivo phosphorylation of IGFBP-5 and its glycan composition.
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Affiliation(s)
- Mark E Graham
- Cell Signalling Unit, Children's Medical Research Institute, Locked Bag 23, Wentworthville, New South Wales 2145, Australia
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Gianazza E, Wait R, Begum S, Eberini I, Campagnoli M, Labò S, Galliano M. Mapping the 5–50-kDa fraction of human amniotic fluid proteins by 2-DE and ESI-MS. Proteomics Clin Appl 2007; 1:167-75. [DOI: 10.1002/prca.200600543] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kuang Z, Yao S, Keizer DW, Wang CC, Bach LA, Forbes BE, Wallace JC, Norton RS. Structure, dynamics and heparin binding of the C-terminal domain of insulin-like growth factor-binding protein-2 (IGFBP-2). J Mol Biol 2006; 364:690-704. [PMID: 17020769 DOI: 10.1016/j.jmb.2006.09.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 08/31/2006] [Accepted: 09/01/2006] [Indexed: 11/24/2022]
Abstract
Insulin-like growth factor-binding protein-2 (IGFBP-2) is the largest member of a family of six proteins (IGFBP-1 to 6) that bind insulin-like growth factors I and II (IGF-I/II) with high affinity. In addition to regulating IGF actions, IGFBPs have IGF-independent functions. The C-terminal domains of IGFBPs contribute to high-affinity IGF binding, and confer binding specificity and have overlapping but variable interactions with many other molecules. Using nuclear magnetic resonance (NMR) spectroscopy, we have determined the solution structure of the C-terminal domain of IGFBP-2 (C-BP-2) and analysed its backbone dynamics based on 15N relaxation parameters. C-BP-2 has a thyroglobulin type 1 fold consisting of an alpha-helix, a three-stranded anti-parallel beta-sheet and three flexible loops. Compared to C-BP-6 and C-BP-1, structural differences that may affect IGF binding and underlie other functional differences were found. C-BP-2 has a longer disordered loop I, and an extended C-terminal tail, which is unstructured and very mobile. The length of the helix is identical with that of C-BP-6 but shorter than that of C-BP-1. Reduced spectral density mapping analysis showed that C-BP-2 possesses significant rapid motion in the loops and termini, and may undergo slower conformational or chemical exchange in the structured core and loop II. An RGD motif is located in a solvent-exposed turn. A pH-dependent heparin-binding site on C-BP-2 has been identified. Protonation of two histidine residues, His271 and His228, seems to be important for this binding, which occurs at slightly acidic pH (6.0) and is more significant at pH 5.5, but is largely suppressed at pH 7.4. Possible preferential binding of IGFBP-2 and its C- domain fragments to glycosaminoglycans in the acidic extracellular matrix (ECM) of tumours may be related to their roles in cancer.
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Affiliation(s)
- Zhihe Kuang
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville 3050, Australia
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Sitar T, Popowicz GM, Siwanowicz I, Huber R, Holak TA. Structural basis for the inhibition of insulin-like growth factors by insulin-like growth factor-binding proteins. Proc Natl Acad Sci U S A 2006; 103:13028-33. [PMID: 16924115 PMCID: PMC1551901 DOI: 10.1073/pnas.0605652103] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Insulin-like growth factor-binding proteins (IGFBPs) control bioavailability, activity, and distribution of insulin-like growth factor (IGF)1 and -2 through high-affinity IGFBP/IGF complexes. IGF-binding sites are found on N- and C-terminal fragments of IGFBPs, the two conserved domains of IGFBPs. The relative contributions of these domains to IGFBP/IGF complexation has been difficult to analyze, in part, because of the lack of appropriate three-dimensional structures. To analyze the effects of N- and C-terminal domain interactions, we determined several x-ray structures: first, of a ternary complex of N- and C-terminal domain fragments of IGFBP4 and IGF1 and second, of a "hybrid" ternary complex using the C-terminal domain fragment of IGFBP1 instead of IGFBP4. We also solved the binary complex of the N-terminal domains of IGFBP4 and IGF1, again to analyze C- and N-terminal domain interactions by comparison with the ternary complexes. The structures reveal the mechanisms of IGF signaling regulation via IGFBP binding. This finding supports research into the design of IGFBP variants as therapeutic IGF inhibitors for diseases of IGF disregulation. In IGFBP4, residues 1-38 form a rigid disulphide bond ladder-like structure, and the first five N-terminal residues bind to IGF and partially mask IGF residues responsible for the type 1 IGF receptor binding. A high-affinity IGF1-binding site is located in a globular structure between residues 39 and 82. Although the C-terminal domains do not form stable binary complexes with either IGF1 or the N-terminal domain of IGFBP4, in the ternary complex, the C-terminal domain contacts both and contributes to blocking of the IGF1 receptor-binding region of IGF1.
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Affiliation(s)
- Tomasz Sitar
- Max-Planck-Institut für Biochemie, D-82152 Martinsried, Germany
| | | | - Igor Siwanowicz
- Max-Planck-Institut für Biochemie, D-82152 Martinsried, Germany
| | - Robert Huber
- Max-Planck-Institut für Biochemie, D-82152 Martinsried, Germany
- *To whom correspondence may be addressed. E-mail:
or
| | - Tad A. Holak
- Max-Planck-Institut für Biochemie, D-82152 Martinsried, Germany
- *To whom correspondence may be addressed. E-mail:
or
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Beattie J, Allan GJ, Lochrie JD, Flint DJ. Insulin-like growth factor-binding protein-5 (IGFBP-5): a critical member of the IGF axis. Biochem J 2006; 395:1-19. [PMID: 16526944 PMCID: PMC1409685 DOI: 10.1042/bj20060086] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2006] [Accepted: 01/30/2006] [Indexed: 11/17/2022]
Abstract
The six members of the insulin-like growth factor-binding protein family (IGFBP-1-6) are important components of the IGF (insulin-like growth factor) axis. In this capacity, they serve to regulate the activity of both IGF-I and -II polypeptide growth factors. The IGFBPs are able to enhance or inhibit the activity of IGFs in a cell- and tissue-specific manner. One of these proteins, IGFBP-5, also has an important role in controlling cell survival, differentiation and apoptosis. In this review, we report on the structural and functional features of the protein which are important for these effects. We also examine the regulation of IGFBP-5 expression and comment on its potential role in tumour biology, with special reference to work with breast cancer cells.
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Key Words
- extracellular matrix (ecm)
- glycosaminoglycan
- insulin-like growth factor-i (igf-i)
- insulin-like growth factor-binding protein 5 (igfbp-5)
- mammary gland
- proteolysis
- adam, adisintegrin and metalloprotease
- ap-2, activator protein 2
- cat, chloramphenicol acetyltransferase
- cbp-4, c-terminus of insulin-like growth factor-binding protein 4 (residues 151–232)
- c/ebp, ccaat/enhancer-binding protein
- ecm, extracellular matrix
- er, oestrogen receptor
- erk1/2, extracellular-signal-regulated protein kinase 1/2
- fhl-2, four-and-a-half lim domain 2
- gag, glycosaminoglycan
- gh, growth hormone
- igf, insulin-like growth factor
- igfbp, igf-binding protein
- igf-ir, igf-i receptor
- igf-iir, igf-ii receptor
- ir, insulin receptor
- irs, ir substrate
- mapk, mitogen-activated protein kinase
- nbp-4, n-terminus of igfbp-4 (residues 3–82)
- oe2, oestradiol
- op-1, osteogenic protein-1
- opn, osteopontin
- pai-1, plasminogen activator inhibitor-1
- papp, pregnancy-associated plasma protease
- pge2, prostaglandin e2
- psmc, porcine smooth-muscle cell
- ra, retinoic acid
- rassf1c, isoform c of the ras association family 1 protein group
- rt, reverse transcription
- spr, surface plasmon resonance
- tpa, tissue plasminogen activator
- tsp-1, thrombospondin-1
- vn, vitronectin
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Affiliation(s)
- James Beattie
- Hannah Research Institute, Ayr KA6 5HL, Scotland, UK.
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Kibbey MM, Jameson MJ, Eaton EM, Rosenzweig SA. Insulin-like growth factor binding protein-2: contributions of the C-terminal domain to insulin-like growth factor-1 binding. Mol Pharmacol 2005; 69:833-45. [PMID: 16306230 DOI: 10.1124/mol.105.016998] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Signaling by the insulin-like growth factor (IGF)-1 receptor (IGF-1R) has been implicated in the promotion and aggressiveness of breast, prostate, colorectal, and lung cancers. The IGF binding proteins (IGFBPs) represent a class of natural IGF antagonists that bind to and sequester IGF-1/2 from the IGF-1R, making them attractive candidates as therapeutics for cancer prevention and control. Recombinant human IGFBP-2 significantly attenuated IGF-1-stimulated MCF-7 cell proliferation with coaddition of 20 or 100 nM IGFBP-2 (50 or 80% inhibition, respectively). We previously identified IGF-1 contact sites both upstream and downstream of the CWCV motif (residues 247-250) in human IGFBP-2 (J Biol Chem 276:2880-2889, 2001). To further test their contributions to IGFBP-2 function, the single tryptophan in human IGFBP-2, Trp-248, was selectively cleaved with 2-(2'nitrophenylsulfenyl)-3-methyl-3 bromoindolenine (BNPS-skatole) and the BNPS-skatole products IGFBP-2(1-248) and IGFBP-2(249-289) as well as IGFBP-2(1-190) were expressed as glutathione S-transferase-fusion proteins and purified. Based on competition binding analysis, deletion of residues 249 to 289 caused an approximately 20-fold decrease in IGF-1 binding affinity (IGFBP-2 EC50 = 0.35 nM and IGFBP-2(1-248) = 7 nM). Removal of the remainder of the C-terminal domain had no further effect on affinity (IGFBP-2(1-190) EC50 = 9.2 nM). In kinetic assays, IGFBP-2(1-248) and IGFBP-2(1-190) exhibited more rapid association and dissociation rates than full-length IGFBP-2. These results confirm that regions upstream and downstream of the CWCV motif participate in IGF-1 binding. They further support the development of full-length IGFBP-2 as a cancer therapeutic.
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Affiliation(s)
- Megan M Kibbey
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC 29425, USA
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