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Wang F, Chen Y, Zou CJ, Luo R, Yang T. Mutagenesis of the Cleavage Site of Pro Renin Receptor Abrogates Angiotensin II-Induced Hypertension in Mice. Hypertension 2021; 78:115-127. [PMID: 34024121 PMCID: PMC9212214 DOI: 10.1161/hypertensionaha.121.16770] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Fei Wang
- Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - Yanting Chen
- Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - Chang-jiang Zou
- Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - Renfei Luo
- Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - Tianxin Yang
- Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah, USA
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Feng Y, Peng K, Luo R, Wang F, Yang T. Site-1 Protease-Derived Soluble (Pro)Renin Receptor Contributes to Angiotensin II-Induced Hypertension in Mice. Hypertension 2021; 77:405-416. [PMID: 33280408 PMCID: PMC7803453 DOI: 10.1161/hypertensionaha.120.15100] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Activation of PRR ([pro]renin receptor) contributes to enhancement of intrarenal RAS and renal medullary α-ENaC and thus elevated blood pressure during Ang II (angiotensin II) infusion. The goal of the present study was to test whether such action of PRR was mediated by sPRR (soluble PRR), generated by S1P (site-1 protease), a newly identified PRR cleavage protease. F1 B6129SF1/J mice were infused for 6 days with control or Ang II at 300 ng/kg per day alone or in combination with S1P inhibitor PF-429242 (PF), and blood pressure was monitored by radiotelemetry. S1P inhibition significantly attenuated Ang II-induced hypertension accompanied with suppressed urinary and renal medullary renin levels and expression of renal medullary but not renal cortical α-ENaC expression. The effects of S1P inhibition were all reversed by supplement with histidine-tagged sPRR termed as sPRR-His. Ussing chamber technique was performed to determine amiloride-sensitive short-circuit current, an index of ENaC activity in confluent mouse cortical collecting duct cell line cells exposed for 24 hours to Ang II, Ang II + PF, or Ang II + PF + sPRR-His. Ang II-induced ENaC activity was blocked by PF, which was reversed by sPRR-His. Together, these results support that S1P-derived sPRR mediates Ang II-induced hypertension through enhancement of intrarenal renin level and activation of ENaC.
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Affiliation(s)
- Ye Feng
- From the Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City
| | - Kexin Peng
- From the Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City
| | - Renfei Luo
- From the Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City
| | - Fei Wang
- From the Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City
| | - Tianxin Yang
- From the Department of Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City
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Palanikumar I, Katla S, Tahara N, Yui M, Zhang R, Ebihara A, Sivaprakasam S. Heterologous expression, purification, and functional characterization of recombinant ovine angiotensinogen in the methylotrophic yeast Pichia pastoris. Biotechnol Prog 2019; 35:e2866. [PMID: 31187608 DOI: 10.1002/btpr.2866] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/22/2019] [Accepted: 06/04/2019] [Indexed: 12/26/2022]
Abstract
Angiotensinogen (AGT), a glycosylated plasma noninhibitory serpin, serves as a precursor for angiotensin peptides which regulate blood pressure and electrolyte balance. AGT is specifically cleaved by renin to produce angiotensin-I, the first product of the angiotensin-processing cascade. Ovine angiotensinogen (oAGT) is considered an effective substrate for human renin and consequently finds application in clinical renin assays. In this study, oAGT was cloned into the genome of Pichia pastoris and expressed under the control of alcohol oxidase (AOX1) promoter for high-level production. Compared to the shake flask study, the high cell density cultivation in bioreactor resulted in multifold increase in oAGT titer (420 ± 9.26 mg/L), which is its highest reported titer to date. We purified recombinant oAGT to homogeneity using two chromatography steps. The characterization studies revealed oAGT underwent a two-state transition during thermal denaturation process as assessed by differential scanning fluorimetry, and the melting temperature (Tm ) of the purified oAGT from P. pastoris was 48.3°C. Renin reactivity with recombinant oAGT from P. pastoris (0.51 nM angiotensin-I/min) was slightly lower than the renin reactivity for recombinant oAGT from Escherichia coli (0.67 nM angiotensin-I/min), possibly because of its mannosylated N-glycan content. Enhanced production of functionally active recombinant oAGT using P. pastoris expression system reported in this study envisage the effective utilization of oAGT in clinical studies related to renin in near future.
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Affiliation(s)
| | - Srikanth Katla
- BioPAT Laboratory, Indian Institute of Technology Guwahati, Guwahati, Assam, India
| | - Nariyasu Tahara
- Graduate School of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Midori Yui
- Graduate School of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Rui Zhang
- Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan
| | - Akio Ebihara
- Faculty of Applied Biological Sciences, Gifu University, Gifu, Japan.,Center for Highly Advanced Integration of Nano and Life Sciences, Gifu University (G-CHAIN), Gifu, Japan
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Akther J, Nabi AN, Ohno S, Yokogawa T, Nakagawa T, Suzuki F, Ebihara A. Establishing a novel assay system for measuring renin concentration using cost effective recombinant ovine angiotensinogen. Heliyon 2019; 5:e01409. [PMID: 30997427 PMCID: PMC6451169 DOI: 10.1016/j.heliyon.2019.e01409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 02/10/2019] [Accepted: 03/20/2019] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Plasma renin can predict future cardiovascular events as well as the prevalence of chronic renal disease in hypertensive subjects. Ovine angiotensinogen (oANG) is a better substrate for measuring renin concentration through activity assay. Recombinant oANG expressed in Escherichia coli cells can be utilized as the substrate while measuring plasma renin. We aim to establish an immunoassay for measuring renin concentration at picomolar level using recombinant oANG. MATERIAL AND METHODS Recombinant oANG was expressed in E. coli cells and purified to homogeneity. Various concentrations (0-1.5 pM) of recombinant human renin standard were prepared and incubated with recombinant oANG. Renin activity was determined by angiotensin-I specific enzyme-linked immunosorbent assay. RESULTS About 4.5 mg of purified recombinant oANG was obtained from 0.5 L of E. coli culture. The Michaelis constant and turnover number of human renin with recombinant oANG were 0.16 μM and 0.51 s-1, respectively. A linear relationship was obtained when renin activity was plotted as a function of renin concentration using recombinant oANG as the renin substrate. Picomolar amounts of renin can be measured from known renin activity using this method. CONCLUSION This study established a novel assay system for measuring renin at picomolar level using cost effective recombinant oANG.
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Affiliation(s)
- Jobaida Akther
- United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
- Laboratory of Population Genetics, Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, 1000, Bangladesh
| | - A.H.M. Nurun Nabi
- Laboratory of Population Genetics, Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, 1000, Bangladesh
| | - Satoshi Ohno
- Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Takashi Yokogawa
- Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
- Center for Highly Advanced Integration of Nano and Life Sciences, Gifu University (G-CHAIN), 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Tsutomu Nakagawa
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Fumiaki Suzuki
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Akio Ebihara
- Center for Highly Advanced Integration of Nano and Life Sciences, Gifu University (G-CHAIN), 1-1 Yanagido, Gifu, 501-1193, Japan
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
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Suzuki F. Nonproteolytic activation of prorenin by the (pro)renin receptor is blocked by decoy peptide. J Renin Angiotensin Aldosterone Syst 2016; 8:101-3. [PMID: 17703437 DOI: 10.3317/jraas.2007.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Affiliation(s)
- Fumiaki Suzuki
- Lab.Animal Biochem., Fac.Appl. Biol. Sci., Gifu University,Yanagido 1-1, 501-1193 Gifu, Japan
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Xu C, Lu A, Wang H, Fang H, Zhou L, Sun P, Yang T. (Pro)Renin receptor regulates potassium homeostasis through a local mechanism. Am J Physiol Renal Physiol 2016; 313:F641-F656. [PMID: 27440776 DOI: 10.1152/ajprenal.00043.2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 07/12/2016] [Accepted: 07/18/2016] [Indexed: 11/22/2022] Open
Abstract
(Pro)renin receptor (PRR) is highly expressed in the distal nephron, but it has an unclear functional implication. The present study was conducted to explore a potential role of renal PRR during high K+ (HK) loading. In normal Sprague-Dawley rats, a 1-wk HK intake increased renal expression of full-length PRR and urinary excretion of soluble PRR (sPRR). Administration of PRO20, a decoy peptide antagonist of PRR, in K+-loaded animals elevated plasma K+ level and decreased urinary K+ excretion, accompanied with suppressed urinary aldosterone excretion and intrarenal aldosterone levels. HK downregulated Na+-Cl- cotransporter (NCC) expression but upregulated CYP11B2 (cytochrome P-450, family 11, subfamily B, polypeptide 2), renal outer medullary K+ channel (ROMK), calcium-activated potassium channel subunit α1 (α-BK), α-Na+-K+-ATPase (α-NKA), and epithelial Na+ channel subunit β (β-ENaC), all of which were blunted by PRO20. After HK loading was completed, urinary, but not plasma renin, was upregulated, which was blunted by PRO20. The same experiments that were performed using adrenalectomized (ADX) rats yielded similar results. Interestingly, spironolactone treatment in HK-loaded ADX rats attenuated kaliuresis but promoted natriuresis, which was associated with the suppressed responses of β-ENaC, α-NKA, ROMK, and α-BK protein expression. Taken together, we discovered a novel role of renal PRR in regulation of K+ homeostasis through a local mechanism involving intrarenal renin-angiotensin-aldosterone system and coordinated regulation of membrane Na+- and K+-transporting proteins.
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Affiliation(s)
- Chuanming Xu
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China
| | - Aihua Lu
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China
| | - Hong Wang
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China
| | - Hui Fang
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China
| | - Li Zhou
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China
| | - Peng Sun
- Anesthesiology, Sun Yat-sen University Cancer Center, Guangzhou, China; and
| | - Tianxin Yang
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China; .,Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah
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Yamashita S, Shibata N, Boku-Ikeda A, Abe E, Inayama A, Yamaguchi T, Higuma A, Inagaki K, Tsuyuzaki T, Iwamoto S, Ohno S, Yokogawa T, Nishikawa K, Biswas KB, Nabi AHMN, Nakagawa T, Suzuki F, Ebihara A. Escherichia coli-based production of recombinant ovine angiotensinogen and its characterization as a renin substrate. BMC Biotechnol 2016; 16:33. [PMID: 27052373 PMCID: PMC4823841 DOI: 10.1186/s12896-016-0265-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 03/30/2016] [Indexed: 11/10/2022] Open
Abstract
Background Angiotensinogen (ANG) is a macromolecular precursor of angiotensin, which regulates blood pressure and electrolyte balance. ANG is specifically cleaved by renin, an aspartic protease, to initiate the angiotensin-processing cascade. Ovine ANG (oANG) from sheep plasma has been shown to be a better substrate for human renin, and it has been used in clinical renin assays. To expand the availability of oANG, we aimed to produce milligram levels of recombinant oANG using an Escherichia coli expression system. Results When recombinant oANG was expressed from a T7 promoter in various E. coli strains at 37 °C, it accumulated in the insoluble fraction. However, by expressing oANG at 37 °C from a tac promoter, which has weaker transcriptional activity than a T7 promoter, we significantly elevated the ratio of soluble to insoluble recombinant oANG. Using a novel culturing system and auto-induction culture medium, we purified tac-expressed recombinant oANG to homogeneity, with a yield of 4.0 mg per liter of culture. Based on size-exclusion gel filtration analysis and dynamic light scattering analysis, the resulting purified oANG is a monomer in solution. The circular dichroism spectrum of E. coli-expressed recombinant oANG was similar to that of oANG expressed in CHO cells. Differential scanning fluorimetry showed that both preparations undergo a two-state transition during thermal denaturation, and the melting temperatures of recombinant oANG expressed in E. coli and CHO cells were 49.4 ± 0.16 °C and 51.6 ± 0.19 °C, respectively. The Km values of both oANG preparations were similar; the kcat value of E. coli-expressed recombinant oANG was slightly higher than that of CHO-expressed oANG. Conclusions Recombinant oANG expressed in E. coli functions as a human renin substrate. This study presents an E. coli-based system for the rapid production of milligram quantities of a human renin substrate, which will be useful for both fundamental and clinical studies on renin and hypertension. Electronic supplementary material The online version of this article (doi:10.1186/s12896-016-0265-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shinji Yamashita
- United Graduate School of Agricultural Science, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Naoya Shibata
- Graduate School of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Akiyoshi Boku-Ikeda
- Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Erika Abe
- Graduate School of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Ayumi Inayama
- Graduate School of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Takashi Yamaguchi
- Graduate School of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Ayano Higuma
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Kaoru Inagaki
- Graduate School of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Tomoyo Tsuyuzaki
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Satoshi Iwamoto
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Satoshi Ohno
- Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Takashi Yokogawa
- Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Kazuya Nishikawa
- Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Kazal Boron Biswas
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - A H M Nurun Nabi
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka-1000, Bangladesh
| | - Tsutomu Nakagawa
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Fumiaki Suzuki
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Akio Ebihara
- Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan.
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Wang F, Lu X, Peng K, Du Y, Zhou SF, Zhang A, Yang T. Prostaglandin E-prostanoid4 receptor mediates angiotensin II-induced (pro)renin receptor expression in the rat renal medulla. Hypertension 2014; 64:369-77. [PMID: 24866147 DOI: 10.1161/hypertensionaha.114.03654] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Angiotensin II (Ang II) stimulates (pro)renin receptor (PRR) expression in the renal collecting duct, triggering the local renin response in the distal nephron. Our recent study provided evidence for involvement of cyclooxygenase-2-prostaglandin E2 pathway in Ang II-dependent stimulation of PRR expression in the collecting duct. Here, we tested the role of E-prostanoid (EP) subtypes acting downstream of cyclooxygenase-2 in this phenomenon. In primary rat inner medullary collecting duct cells, Ang II treatment for 12 hours induced a 1.8-fold increase in the full-length PRR protein expression. To assess the contribution of EP receptor, the cell was pretreated with specific EP receptor antagonists: SC-51382 (for EP1), L-798106 (for EP3), L-161982 (for EP4), and ONO-AE3-208 (ONO, a structurally distinct EP4 antagonist). The upregulation of PRR expression by Ang II was consistently abolished by L-161982 and ONO and partially suppressed by SC-51382 but was unaffected by L-798106. The PRR expression was also significantly elevated by the EP4 agonist CAY10598 in the absence of Ang II. Sprague-Dawley rats were subsequently infused for 1 or 2 weeks with vehicle, Ang II alone, or in combination with ONO. Ang II infusion induced parallel increases in renal medullary PRR protein and renal medullary and urinary renin activity and total renin content, all of which were blunted by ONO. Both tail cuff plethysmography and telemetry demonstrated attenuation of Ang II hypertension by ONO. Overall, these results have established a crucial role of the EP4 receptor in mediating the upregulation of renal medullary PRR expression and renin activity during Ang II hypertension.
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Affiliation(s)
- Fei Wang
- From the Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China (F.W., X.L., K.P., T.Y.); Department of Internal Medicine, University of Utah, Salt Lake City (F.W., X.L., T.Y.); Veterans Affairs Medical Center, Salt Lake City, UT (F.W., X.L., T.Y.); Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China (Y.D.); Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa (S.-F.Z.); and Department of Nephrology, Nanjing Children's Hospital, Affiliated to Nanjing Medical University, Nanjing, China (A.Z.)
| | - Xiaohan Lu
- From the Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China (F.W., X.L., K.P., T.Y.); Department of Internal Medicine, University of Utah, Salt Lake City (F.W., X.L., T.Y.); Veterans Affairs Medical Center, Salt Lake City, UT (F.W., X.L., T.Y.); Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China (Y.D.); Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa (S.-F.Z.); and Department of Nephrology, Nanjing Children's Hospital, Affiliated to Nanjing Medical University, Nanjing, China (A.Z.)
| | - Kexin Peng
- From the Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China (F.W., X.L., K.P., T.Y.); Department of Internal Medicine, University of Utah, Salt Lake City (F.W., X.L., T.Y.); Veterans Affairs Medical Center, Salt Lake City, UT (F.W., X.L., T.Y.); Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China (Y.D.); Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa (S.-F.Z.); and Department of Nephrology, Nanjing Children's Hospital, Affiliated to Nanjing Medical University, Nanjing, China (A.Z.)
| | - Yaomin Du
- From the Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China (F.W., X.L., K.P., T.Y.); Department of Internal Medicine, University of Utah, Salt Lake City (F.W., X.L., T.Y.); Veterans Affairs Medical Center, Salt Lake City, UT (F.W., X.L., T.Y.); Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China (Y.D.); Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa (S.-F.Z.); and Department of Nephrology, Nanjing Children's Hospital, Affiliated to Nanjing Medical University, Nanjing, China (A.Z.)
| | - Shu-Feng Zhou
- From the Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China (F.W., X.L., K.P., T.Y.); Department of Internal Medicine, University of Utah, Salt Lake City (F.W., X.L., T.Y.); Veterans Affairs Medical Center, Salt Lake City, UT (F.W., X.L., T.Y.); Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China (Y.D.); Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa (S.-F.Z.); and Department of Nephrology, Nanjing Children's Hospital, Affiliated to Nanjing Medical University, Nanjing, China (A.Z.)
| | - Aihua Zhang
- From the Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China (F.W., X.L., K.P., T.Y.); Department of Internal Medicine, University of Utah, Salt Lake City (F.W., X.L., T.Y.); Veterans Affairs Medical Center, Salt Lake City, UT (F.W., X.L., T.Y.); Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China (Y.D.); Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa (S.-F.Z.); and Department of Nephrology, Nanjing Children's Hospital, Affiliated to Nanjing Medical University, Nanjing, China (A.Z.)
| | - Tianxin Yang
- From the Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China (F.W., X.L., K.P., T.Y.); Department of Internal Medicine, University of Utah, Salt Lake City (F.W., X.L., T.Y.); Veterans Affairs Medical Center, Salt Lake City, UT (F.W., X.L., T.Y.); Guangdong Provincial People's Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China (Y.D.); Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa (S.-F.Z.); and Department of Nephrology, Nanjing Children's Hospital, Affiliated to Nanjing Medical University, Nanjing, China (A.Z.).
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Wang F, Lu X, Peng K, Zhou L, Li C, Wang W, Yu X, Kohan DE, Zhu SF, Yang T. COX-2 mediates angiotensin II-induced (pro)renin receptor expression in the rat renal medulla. Am J Physiol Renal Physiol 2014; 307:F25-32. [PMID: 24740788 DOI: 10.1152/ajprenal.00548.2013] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
(Pro)renin receptor (PRR) is predominantly expressed in the distal nephron where it is activated by angiotensin II (ANG II), resulting in increased renin activity in the renal medulla thereby amplifying the de novo generation and action of local ANG II. The goal of the present study was to test the role of cycloxygenase-2 (COX-2) in meditating ANG II-induced PRR expression in the renal medulla in vitro and in vivo. Exposure of primary rat inner medullary collecting duct cells to ANG II induced sequential increases in COX-2 and PRR protein expression. When the cells were pretreated with a COX-2 inhibitor NS-398, ANG II-induced upregulation of PRR protein expression was almost completely abolished, in parallel with the changes in medium active renin content. The inhibitory effect of NS-398 on the PRR expression was reversed by adding exogenous PGE2. A 14-day ANG II infusion elevated renal medullary PRR expression and active and total renin content in parallel with increased urinary renin, all of which were remarkably suppressed by the COX-2 inhibitor celecoxib. In contrast, plasma and renal cortical active and total renin content were suppressed by ANG II treatment, an effect that was unaffected by COX-2 inhibition. Systolic blood pressure was elevated with ANG II infusion, which was attenuated by the COX-2 inhibition. Overall, the results obtained from in vitro and in vivo studies established a crucial role of COX-2 in mediating upregulation of renal medullary PRR expression and renin content during ANG II hypertension.
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Affiliation(s)
- Fei Wang
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China; Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah; and
| | - Xiaohan Lu
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China; Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah; and
| | - Kexin Peng
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China; Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah; and
| | - Li Zhou
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China
| | - Chunling Li
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China
| | - Weidong Wang
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China
| | - Xueqing Yu
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Donald E Kohan
- Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah; and
| | - Shu-Feng Zhu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida
| | - Tianxin Yang
- Institute of Hypertension, Sun Yat-sen University School of Medicine, Guangzhou, China; Internal Medicine, University of Utah and Veterans Affairs Medical Center, Salt Lake City, Utah; and
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Toma I, Kang JJ, Sipos A, Vargas S, Bansal E, Hanner F, Meer E, Peti-Peterdi J. Succinate receptor GPR91 provides a direct link between high glucose levels and renin release in murine and rabbit kidney. J Clin Invest 2008; 118:2526-34. [PMID: 18535668 DOI: 10.1172/jci33293] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Accepted: 04/23/2008] [Indexed: 11/17/2022] Open
Abstract
Diabetes mellitus is the most common and rapidly growing cause of end-stage renal disease in developed countries. A classic hallmark of early diabetes mellitus includes activation of the renin-angiotensin system (RAS), which may lead to hypertension and renal tissue injury, but the mechanism of RAS activation is elusive. Here we identified a paracrine signaling pathway in the kidney in which high levels of glucose directly triggered the release of the prohypertensive hormone renin. The signaling cascade involved the local accumulation of succinate and activation of the kidney-specific G protein-coupled metabolic receptor, GPR91, in the glomerular endothelium as observed in rat, mouse, and rabbit kidney sections. Elements of signal transduction included endothelial Ca2+, the production of NO and prostaglandin (PGE2), and their paracrine actions on adjacent renin-producing cells. This GPR91 signaling cascade may serve to modulate kidney function and help remove metabolic waste products through renal hyperfiltration, and it could also link metabolic diseases, such as diabetes, or metabolic syndrome with RAS overactivation, systemic hypertension, and organ injury.
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Affiliation(s)
- Ildikó Toma
- Department of Physiology and Biophysics, University of Southern California, Los Angeles, California 90033, USA
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12
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Kang JJ, Toma I, Sipos A, Meer EJ, Vargas SL, Peti-Peterdi J. The collecting duct is the major source of prorenin in diabetes. Hypertension 2008; 51:1597-604. [PMID: 18413493 DOI: 10.1161/hypertensionaha.107.107268] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In addition to the juxtaglomerular apparatus, renin is also synthesized in renal tubular epithelium, including the collecting duct (CD). Angiotensin (Ang) II differentially regulates the synthesis of juxtaglomerular (inhibition) and CD (stimulation) renin. Because diabetes mellitus, a disease with high intrarenal renin-Ang system and Ang II activity, is characterized by high prorenin levels, we hypothesized that the CD is the major source of prorenin in diabetes. Renin granular content was visualized using in vivo multiphoton microscopy of the kidney in diabetic Munich-Wistar rats. Diabetes caused a 3.5-fold increase in CD renin, in contrast to less pronounced juxtaglomerular changes. Ang II type 1 receptor blockade with Olmesartan reduced CD renin to control levels but significantly increased juxtaglomerular renin. Using a fluorogenic renin assay, the prorenin component of CD renin content was measured by assessing the difference in enzymatic activity of medullary homogenates before and after trypsin activation of prorenin. Trypsinization caused no change in control renin activity but a 5-fold increase in diabetes. Studies on a CD cell line (M1) showed a 22-fold increase in renin activity after trypsinization and a further 35-fold increase with Ang II treatment. Therefore, prorenin significantly contributes to baseline CD renin. Diabetes, possibly via Ang II, greatly stimulates CD prorenin and causes hyperplasia of renin-producing connecting segments. These novel findings suggest that, in a rat model of diabetes, prorenin content and release from the CD may be more important than the juxtaglomerular apparatus in contrast to the existing paradigm.
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Affiliation(s)
- Jung J Kang
- Department of Physiology, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
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13
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Expression and purification of human (pro)renin receptor in insect cells using baculovirus expression system. Protein Expr Purif 2008; 58:242-8. [DOI: 10.1016/j.pep.2007.11.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Revised: 11/19/2007] [Accepted: 11/20/2007] [Indexed: 11/20/2022]
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14
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Ménard J, Azizi M. The difficult conception, birth and delivery of a renin inhibitor: controversies around aliskiren. J Hypertens 2007; 25:1775-82. [PMID: 17762637 DOI: 10.1097/hjh.0b013e3282ef45e9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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15
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Kaneshiro Y, Ichihara A, Sakoda M, Takemitsu T, Nabi AHMN, Uddin MN, Nakagawa T, Nishiyama A, Suzuki F, Inagami T, Itoh H. Slowly progressive, angiotensin II-independent glomerulosclerosis in human (pro)renin receptor-transgenic rats. J Am Soc Nephrol 2007; 18:1789-95. [PMID: 17494887 DOI: 10.1681/asn.2006091062] [Citation(s) in RCA: 193] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
For defining the pathogenic effects of the (pro)renin receptor-transgenic rat, strains that overexpressed the human receptor were generated. Although transgenic rats were normotensive and euglycemic and had a renal angiotensin II (AngII) level that was comparable to that of wild-type rats, transgenic rats developed proteinuria with aging and significant glomerulosclerosis at 28 wk of age. In kidneys of 28-wk-old transgenic rats, mitogen-activated protein kinases (MAPK) were activated without recognizable tyrosine phosphorylation of the EGF receptor, and expression of TGF-beta1 was enhanced. In vivo infusion of the (pro)renin receptor blocker peptide (formerly handle region decoy peptide) significantly inhibited the development of glomerulosclerosis, proteinuria, MAPK activation, and TGF-beta1 expression in the kidneys, but the angiotensin-converting enzyme inhibitor did not attenuate these changes despite a significant decrease in the renal AngII level. In addition, recombinant rat prorenin stimulated MAPK activation in the human receptor-expressed cultured cells, but human receptor was unable to evoke the enzyme activity of rat prorenin. Thus, human (pro)renin receptor elicits slowly progressive nephropathy by AngII-independent MAPK activation in rats. This study clearly provided in vivo evidence for the AngII-independent MAPK activation by human (pro)renin receptor and induction of glomerulosclerosis with increased TGF-beta1 expression.
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Affiliation(s)
- Yuki Kaneshiro
- Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
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16
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Yamamoto T, Nakagawa T, Suzuki H, Ohashi N, Fukasawa H, Fujigaki Y, Kato A, Nakamura Y, Suzuki F, Hishida A. Urinary angiotensinogen as a marker of intrarenal angiotensin II activity associated with deterioration of renal function in patients with chronic kidney disease. J Am Soc Nephrol 2007; 18:1558-65. [PMID: 17409316 DOI: 10.1681/asn.2006060554] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
In chronic kidney disease (CKD), enhanced intrarenal angiotensin II (AngII) is involved in deterioration of renal function, but it is difficult to measure it. For assessment of the potential of urinary angiotensinogen as a marker of intrarenal AngII activity, the correlation of plasma and urinary renin-angiotensin system components, including angiotensinogen, with deterioration of renal function was investigated in 80 patients who had CKD and were not treated with AngII blocking agents. Changes that were induced by 14 d of losartan treatment (25 mg/d) were also measured in 28 patients. Angiotensinogen was measured by RIA of AngI after incubation with renin. Urinary angiotensinogen levels were greater in patients with low estimated GFR and elevated urinary protein and type IV collagen and correlated with renal AngII and type I collagen immunostaining intensities. The risk for deterioration of renal function (i.e., estimated GFR decline of >2.5 ml/min per yr) during a mean follow-up period of 23 mo (maximum 43 mo) was associated with urinary angiotensinogen of >3.0 nmol AngI equivalent per 1 g of urinary creatinine (AngI Eq/g Cre) at enrollment (hazard ratio 3.52). The event-free survival for deterioration of renal function was better in patients with urinary angiotensinogen <3.0 nmol AngI Eq/g Cre than those >3.0 nmol AngI Eq/g Cre. Losartan reduced urinary and plasma angiotensinogen, urinary protein and type IV collagen, and systolic BP, despite concomitant increases in plasma renin and AngII. These data suggest that urinary angiotensinogen is a potentially suitable marker of intrarenal AngII activity associated with increased risk for deterioration of renal function in patients with CKD.
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Affiliation(s)
- Tatsuo Yamamoto
- First Department of Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, Shizuoka, Japan.
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Ichihara A, Kaneshiro Y, Takemitsu T, Sakoda M, Nakagawa T, Nishiyama A, Kawachi H, Shimizu F, Inagami T. Contribution of nonproteolytically activated prorenin in glomeruli to hypertensive renal damage. J Am Soc Nephrol 2006; 17:2495-503. [PMID: 16885412 DOI: 10.1681/asn.2005121278] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Prorenin is activated without proteolysis by binding of prorenin receptor to the pentameric "handle region" (HR) of prorenin prosegment. It was hypothesized that such activation occurs in the kidneys of hypertensive rats and causes tissue renin-angiotensin system (RAS) activation and end-organ damage. Because the HR's binding to its binding protein made the adjacent tetrameric "gate region" (GR) accessible to its specific antibody, immunohistochemistry of the GR was performed to test the hypothesis. Methods also were devised specifically to inhibit the nonproteolytic activation by the decapeptide corresponding to the HR as a decoy. Immunohistochemistry of the GR demonstrated that the majority of nonproteolytically activated prorenin is present in podocytes of the kidneys from stroke-prone spontaneously hypertensive rats, in which activation of renal tissue RAS, proteinuria, and glomerulosclerosis occurred. Continuous subcutaneous administration of the HR decoy peptide completely inhibited both nonproteolytic activation of tissue prorenin and activation of tissue RAS without affecting circulating RAS or arterial pressure and significantly attenuated the development and progression of proteinuria and glomerulosclerosis. These studies clearly demonstrated that nonproteolytic activation of prorenin in glomeruli is critically involved in renal tissue RAS activation, leading to renal damage in hypertensive animals.
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Affiliation(s)
- Atsuhiro Ichihara
- Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
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Ménard J, Guyene TT, Peyrard S, Azizi M. Conformational changes in prorenin during renin inhibition in vitro and in vivo. J Hypertens 2006; 24:529-34. [PMID: 16467656 DOI: 10.1097/01.hjh.0000209989.59230.2e] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Some renin inhibitors induce changes in the conformation of prorenin in vitro and influence the quantification of active renin by immunoradiometric assays. Whether such changes in renin recognition by monoclonal antibodies exist after oral administration of aliskiren, the first orally available renin inhibitor, is not known. METHODS Two commercially available immunoradiometric assays (Cisbio and Nichols) were compared to determine immunoreactive active renin concentrations in plasma samples collected in a single oral dose crossover study comparing the renin inhibitor, aliskiren (300 mg), with the angiotensin II antagonist, valsartan (160 mg), in healthy male subjects. RESULTS The addition of aliskiren to plasma samples in vitro, at concentrations of 1-100 micromol/l, increased active renin immunoreactivity in both the Cisbio and Nichols assays. In the crossover study, the two assays gave similar values for the plasma immunoreactive active renin concentration before treatment and following valsartan administration (intraclass coefficient for agreement between the two assays = 0.92). However, a Bland-Altman plot showed a systematic bias towards higher values (1.75-fold higher; 95% confidence interval = 1.02-3.01) in the Nichols than in the Cisbio assay following aliskiren administration. The difference between the results obtained with the two assays depended on incubation time. CONCLUSIONS Depending on incubation conditions, circulating renin inhibitors interfere with the recognition of active renin molecules by the monoclonal antibodies used in commercially available assays. Careful consideration must therefore be given to the methodology used for quantifying immunoreactive plasma active renin when patients are treated with renin inhibitors, to avoid an overestimation of the magnitude of active renin release attributable to conformational changes in plasma prorenin.
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Affiliation(s)
- Joël Ménard
- Université Paris-Descartes, Faculté de Médecine, INSERM-AP-HP Clinical Investigation Center, Hôpital Européen Georges Pompidou, Paris, France.
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Suzuki F, Hayakawa M, Nakagawa T, Nasir UM, Ebihara A, Iwasawa A, Ishida Y, Nakamura Y, Murakami K. Human prorenin has "gate and handle" regions for its non-proteolytic activation. J Biol Chem 2003; 278:22217-22. [PMID: 12684512 DOI: 10.1074/jbc.m302579200] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We investigated the mechanism for non-proteolytic activation of human prorenin using five kinds of antibodies. Each of the antigens, L1PPTDTTTFKRI11P, T7PFKRIFLKRMP17P, I11PFLKRMPSIRESLKER26P, M16PPSIRESLKER26P, and G27PVDMARLGPEWSQPM41P, was designed from the tertiary structure of predicted prorenin. These antibodies were labeled anti-01/06, anti-07/10, anti-11/26, anti-16/26, and anti-27/41, respectively, for their binding specificities. Inactive recombinant human prorenin (0.1 nM) bound to various concentrations of anti-01/06, anti-11/26, and anti-27/41 antibodies at 4 degrees C with equilibrium dissociation constants of 138, 41, and 22 nM, respectively. However, intact prorenin (0.1 nM) did not show significant binding to 200 nM anti-07/10 and anti-16/26 antibodies for 20 h. Ninety percent of prorenin (0.1 nM) was found to be non-proteolytically activated by incubation with anti-11/26 antibodies (200 nM) at 4 degrees C for 20 h. Prorenin was not active even under complex with either anti-01/06 or anti-27/41 antibodies. Prorenin was also reversibly activated at pH 3.3 and 4 degrees C for 25 h. The acid-activated prorenin bound to anti-07/10 and anti-16/26 antibodies as well as to anti-01/06, anti-11/15, and anti-27/41 antibodies at neutral pH and 4 degrees C in 2 h. Their dissociation constants were 13, 40, 8.6, 3.6, and 14 nM, respectively. The acid-activated prorenin was re-inactivated by incubation at pH 7.4 and 4 degrees C in 50 h. Anti-07/10 and anti-11/26 antibodies inhibited such re-inactivation at 25 degrees C by more than 90% and 50%, respectively, whereas other kinds of antibodies did not prevent the re-inactivation at 25 degrees C. These results indicate that prorenin has "gate" (T7PFKR10P) and "handle" (I11PFLKR15P) regions critical for its non-proteolytic activation.
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Affiliation(s)
- Fumiaki Suzuki
- Molecular Genetics Research Center, Gifu University, Yanagido, Gifu 501-1193, Japan.
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Ma B, Tsai CJ, Nussinov R. Binding and folding: in search of intramolecular chaperone-like building block fragments. PROTEIN ENGINEERING 2000; 13:617-27. [PMID: 11054456 DOI: 10.1093/protein/13.9.617] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
We propose an intramolecular chaperone which catalyzes folding and neither dissociates nor is cleaved. This uncleaved foldase is an intramolecular chain-linked chaperone, which constitutes a critical building block of the structure. Macroscopically, all molecular chaperones facilitate folding reactions and manifest similar energy landscapes. However, microscopically they differ. While intermolecular chaperones catalyze folding by unfolding misfolded conformations or prevent misfolding, the chain-linked cleaved (proregion) and uncleaved intramolecular chaperone-like building blocks suggested here, catalyze folding by binding to, stabilizing and increasing the populations of native conformations of adjacent building block fragments. In both, the more stable the intramolecular chaperone fragment region, the faster is the folding rate. Hence, mechanistically, intramolecular chaperones and chaperone-like segments are similar. Both play a dual role, in folding and in protein function. However, while the functional role of the proregions is inhibitory, necessitating their cleavage, the function of the uncleaved intramolecular chaperone-like building blocks does not require their subsequent removal. On the contrary, it requires that they remain in the structure. This may lead to the difference in the type of control they are under: proteins folding with the assistance of the proregion have been shown to be under kinetic control. It has been suggested that kinetically controlled folding reactions, with the proregion catalyst removed, lend longevity under harsh conditions. On the other hand, proteins with uncleaved intramolecular chaperone-like building blocks, with their 'foldases' still attached, are largely under thermodynamic control, consistent with the control observed in most protein folding reactions. We propose that an uncleaved intramolecular chaperone-like fragment occurs frequently in proteins. We further propose that such proteins would be prone to changing conditions and in particular, to mutations in this critical building block region. We describe the features qualifying it for its proposed chaperone-like role, compare it with inter- and intramolecular chaperones and review current literature in this light. We further propose a mechanism showing how it lowers the barrier heights, leading to faster folding reaction rates. Since these fragments constitute an intergal part of the protein structure, we call these critical building blocks intramolecular, chaperone-like fragments, to clarify, distinguish and adhere to the definition of the transiently associating chaperones. The new mechanism presented here differs from the concept of 'folding nuclei'. While the concept of folding nuclei focuses on a non-sequential distribution of the folding information along the entire protein chain, the chaperone-like building block fragments proposition focuses on a segmental distribution of the folding information. This segmental distribution controls the distributions of the populations throughout the hierarchical folding processes.
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Affiliation(s)
- B Ma
- Laboratory of Experimental and Computational Biology and Intramural Research Support Program-SAIC, Laboratory of Experimental and Computational Biology, NCI-FCRDC, Bldg 469, Rm 151, Frederick, MD 21702, USA
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