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Zucchelli S, Patrucco L, Persichetti F, Gustincich S, Cotella D. Engineering Translation in Mammalian Cell Factories to Increase Protein Yield: The Unexpected Use of Long Non-Coding SINEUP RNAs. Comput Struct Biotechnol J 2016; 14:404-410. [PMID: 27872686 PMCID: PMC5107644 DOI: 10.1016/j.csbj.2016.10.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/21/2016] [Accepted: 10/24/2016] [Indexed: 12/26/2022] Open
Abstract
Mammalian cells are an indispensable tool for the production of recombinant proteins in contexts where function depends on post-translational modifications. Among them, Chinese Hamster Ovary (CHO) cells are the primary factories for the production of therapeutic proteins, including monoclonal antibodies (MAbs). To improve expression and stability, several methodologies have been adopted, including methods based on media formulation, selective pressure and cell- or vector engineering. This review presents current approaches aimed at improving mammalian cell factories that are based on the enhancement of translation. Among well-established techniques (codon optimization and improvement of mRNA secondary structure), we describe SINEUPs, a family of antisense long non-coding RNAs that are able to increase translation of partially overlapping protein-coding mRNAs. By exploiting their modular structure, SINEUP molecules can be designed to target virtually any mRNA of interest, and thus to increase the production of secreted proteins. Thus, synthetic SINEUPs represent a new versatile tool to improve the production of secreted proteins in biomanufacturing processes.
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Affiliation(s)
- Silvia Zucchelli
- Department of Health Sciences, Università del Piemonte Orientale, Novara, Italy; Area of Neuroscience, SISSA, Trieste, Italy
| | - Laura Patrucco
- Department of Health Sciences, Università del Piemonte Orientale, Novara, Italy
| | | | - Stefano Gustincich
- Area of Neuroscience, SISSA, Trieste, Italy; Department of Neuroscience and Brain Technologies, Italian Institute of Technology (IIT), Genova, Italy
| | - Diego Cotella
- Department of Health Sciences, Università del Piemonte Orientale, Novara, Italy
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Hunt SM, Pak SC, Bridges MW, Gray PP, Sleigh MJ. Chinese hamster ovary cells produce sufficient recombinant insulin-like growth factor I to support growth in serum-free medium. Serum-free growth of IGF-I-producing CHO cells. Cytotechnology 2012; 24:55-64. [PMID: 22358597 DOI: 10.1023/a:1007969502256] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Insulin-like growth factor I has similar mitogenic effects to insulin, a growth factor required by most cells in culture, and it can replace insulin in serum-free formulations for some cells. Chinese Hamster Ovary cells grow well in serum-free medium with insulin and transferrin as the only exogenous growth factors. An alternative approach to addition of exogenous growth factors to serum-free medium is transfection of host cells with growth factor-encoding genes, permitting autocrine growth. Taking this approach, we constructed an IGF-I heterologous gene driven by the cytomegalovirus promoter, introduced it into Chinese Hamster Ovary cells and examined the growth characteristics of Insulin-like growth factor I-expressing clonal cells in the absence of the exogenous factor. The transfected cells secreted up to 500 ng/10(6) cells/day of mature Insulin-like growth factor I into the conditioned medium and as a result they grew autonomously in serum-free medium containing transferrin as the only added growth factor. This growth-stimulating effect, observed under both small and large scale culture conditions, was maximal since no further improvement was observed in the presence of exogenous insulin.
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Affiliation(s)
- S M Hunt
- Department of Biotechnology, University of New South Wales, Kensington, NSW, Australia
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Casales E, Aranda A, Quetglas JI, Ruiz-Guillen M, Rodriguez-Madoz JR, Prieto J, Smerdou C. A novel system for the production of high levels of functional human therapeutic proteins in stable cells with a Semliki Forest virus noncytopathic vector. N Biotechnol 2010; 27:138-48. [PMID: 20188220 DOI: 10.1016/j.nbt.2010.02.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 02/15/2010] [Accepted: 02/17/2010] [Indexed: 01/18/2023]
Abstract
Semliki Forest virus (SFV) vectors lead to high protein expression in mammalian cells, but expression is transient due to vector cytopathic effects, inhibition of host cell proteins and RNA-based expression. We have used a noncytopathic SFV mutant (ncSFV) RNA vector to generate stable cell lines expressing two human therapeutic proteins: insulin-like growth factor I (IGF-I) and cardiotrophin-1 (CT-1). Therapeutic genes were fused at the carboxy-terminal end of Puromycin N-acetyl-transferase gene by using as a linker the sequence coding for foot-and-mouth disease virus (FMDV) 2A autoprotease. These cassettes were cloned into the ncSFV vector. Recombinant ncSFV vectors allowed rapid and efficient selection of stable BHK cell lines with puromycin. These cells expressed IGF-I and CT-1 in supernatants at levels reaching 1.4 and 8.6 microg/10(6)cells/24 hours, respectively. Two cell lines generated with each vector were passaged ten times during 30 days, showing constant levels of protein expression. Recombinant proteins expressed at different passages were functional by in vitro signaling assays. Stability at RNA level was unexpectedly high, showing a very low mutation rate in the CT-1 sequence, which did not increase at high passages. CT-1 was efficiently purified from supernatants of ncSFV cell lines, obtaining a yield of approximately 2mg/L/24 hours. These results indicate that the ncSFV vector has a great potential for the production of recombinant proteins in mammalian cells.
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Affiliation(s)
- Erkuden Casales
- Center for Applied Medical Research, University of Navarra, Pamplona, Spain
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4
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Vai M, Brambilla L, Orlandi I, Rota N, Ranzi BM, Alberghina L, Porro D. Improved secretion of native human insulin-like growth factor 1 from gas1 mutant Saccharomyces cerevisiae cells. Appl Environ Microbiol 2000; 66:5477-9. [PMID: 11097931 PMCID: PMC92485 DOI: 10.1128/aem.66.12.5477-5479.2000] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We studied the secretion of recombinant human insulin-like growth factor 1 (rhIGF-1) from transformed yeast cells. The hIGF-1 gene was fused to the mating factor alpha prepro- leader sequence under the control of the constitutive ACT1 promoter. We found that the inactivation of the GAS1 gene in the host strain led to a supersecretory phenotype yielding a considerable increase, from 8 to 55 mg/liter, in rhIGF-1 production.
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Affiliation(s)
- M Vai
- Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, 20126 Milan, Italy
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Koman A, Cazaubon S, Couraud PO, Ullrich A, Strosberg AD. Molecular characterization and in vitro biological activity of placentin, a new member of the insulin gene family. J Biol Chem 1996; 271:20238-41. [PMID: 8702754 DOI: 10.1074/jbc.271.34.20238] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Insulin and insulin-like growth factors belong to a family of polypeptides involved in essential physiological processes. Placentin, a new member of the insulin family, was recently identified as a 139-amino acid open reading frame from a cDNA clone isolated from a subtracted library of first trimester human placenta. Tris/Tricine/SDS-polyacrylamide gel electrophoresis and immunoblot analyses of histidine-tagged recombinant placentin indicate that it is composed of two peptide chains of apparent molecular masses of 4 and 13 kDa. Conditioned media produced by recombinant expression of placentin cDNA in the placental 3AsubE cell line were assayed for biological activity and found to stimulate tyrosine phosphorylation and DNA synthesis. While these effects closely mimicked those of insulin, they were not mediated by the insulin receptor as shown by the lack of tyrosine phosphorylation of this receptor upon placentin treatment. Moreover, in cytotrophoblast primary culture, production of chorionic gonadotropin, a marker of trophoblast differentiation, was increased upon treatment with placentin-conditioned media, while unaffected by insulin. These results suggest that placentin might participate in the cellular proliferation and/or differentiation processes during placental development.
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Affiliation(s)
- A Koman
- Department of Molecular Biology, Max-Planck-Institut für Biochemie, Am Klopferspitz 18A, 82512 Martinsried, Federal Republic of Germany
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Prieto PA, Mukerji P, Kelder B, Erney R, Gonzalez D, Yun JS, Smith DF, Moremen KW, Nardelli C, Pierce M. Remodeling of mouse milk glycoconjugates by transgenic expression of a human glycosyltransferase. J Biol Chem 1995; 270:29515-9. [PMID: 7493992 DOI: 10.1074/jbc.270.49.29515] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The mammary gland is a unique biosynthetic tissue that produces a variety of species-specific glycoconjugates, but the factors regulating the production of specific glycoconjugates are not well understood. To explore the underlying regulation, a fusion gene containing a cDNA encoding the human alpha 1,2-fucosyltransferase (alpha 1,2FT), which generates the H-blood group antigen, flanked by the murine whey acidic protein promoter and a polyadenylation signal, was introduced into mice. Milk samples from transgenic animals contained soluble forms of the alpha 1,2FT, as revealed by Western blots of milk samples using an anti-alpha 1,2FT antiserum and by the demonstration of alpha 1,2FT enzyme activity. Milk from transgenic animals also contained large quantities of 2'-fucosyllactose (Fuc alpha 1-2Gal beta 1-4Glc) and modified glycoproteins containing the H-antigen, whereas milk from control animals lacked these glycoconjugates. Expression levels of 2'-fucosyllactose were high in most animals and represented 1/3 to nearly 1/2 of the total milk oligosaccharides. These results demonstrate that heterologous transgenic expression of a glycosyltransferase can result in the expression of both the transgene and its secondary gene products and that the structures of milk oligosaccharides can be remodeled depending on expression of the appropriate enzyme. Furthermore, these results suggest that the lactating mammary gland may be a unique biosynthetic reactor for the production of biologically active oligosaccharides and glycoconjugates.
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Affiliation(s)
- P A Prieto
- Ross Products Division, Abbott Laboratories, Columbus, Ohio 43219, USA
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Schmidt WK, Moore HP. Synthesis and targeting of insulin-like growth factor-I to the hormone storage granules in an endocrine cell line. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)47133-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Cascieri MA, Bayne ML. Analysis of the interaction of IGF-I analogs with the IGF-I receptor and IGF binding proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1994; 343:33-40. [PMID: 7514345 DOI: 10.1007/978-1-4615-2988-0_4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Distinct domains of IGF-I are important for maintaining high affinity for the IGF-I receptor and for the various species of IGFBPs. The analogs that selectively bind the receptor have proven useful in determining the relative importance of IGFBPs in the regulation of the biological activity of IGF-I. Analogs with poor affinity for the receptor have also been useful in order to demonstrate that a given activity of IGF-I is mediated by the type 1 IGF receptor. These studies confirm that the role of these various proteins in IGF-I action is complex, and may be cell or tissue-type specific.
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Affiliation(s)
- M A Cascieri
- Department of Molecular Pharmacology and biochemistry, Merck Research Laboratories, Rahway, NJ 07065
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Slieker LJ, Brooke GS, Chance RE, Fan L, Hoffmann JA, Howey DC, Long HB, Mayer J, Shields JE, Sundell KL. Insulin and IGF-I analogs: novel approaches to improved insulin pharmacokinetics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1994; 343:25-32. [PMID: 8184740 DOI: 10.1007/978-1-4615-2988-0_3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- L J Slieker
- Diabetes Research Division, Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, IN 46285
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Steube K, Chaudhuri B, Märki W, Merryweather JP, Heim J. Alpha-factor-leader-directed secretion of recombinant human-insulin-like growth factor I from Saccharomyces cerevisiae. Precursor formation and processing in the yeast secretory pathway. EUROPEAN JOURNAL OF BIOCHEMISTRY 1991; 198:651-7. [PMID: 2050146 DOI: 10.1111/j.1432-1033.1991.tb16063.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A synthetic gene coding for human-insulin-like growth factor I (IGFI) was fused to the leader sequence of yeast prepro-alpha-factor and expressed in Saccharomyces cerevisiae under the control of a glyceraldehyde-3-phosphate dehydrogenase promoter fragment. Recombinant IGFI was found inside yeast cells and secreted into the medium. The secreted IGFI migrated on SDS gels with the same electrophoretic mobility as authentic IGFI, i.e. at about 7.5 kDa. HPLC analysis of secreted IGFI revealed the presence of the correctly folded, genuine molecule as well as an isomeric byproduct of equal molecular mass but with two of the three disulfide bonds interchanged. Inside exponentially growing cells the 7.5-kDa IGFI was also found, along with up to four additional IGFI-related polypeptides of higher molecular mass. By endoglycosidase F treatment the three polypeptides between 19-26 kDa were converted to a single peptide of 17 kDa. Since this peptide also reacted with an anti-alpha-factor antibody, it represents most likely the unglycosylated alpha-factor--IGFI fusion precursor. Pulse-chase experiments established the precursor nature of the intracellular higher-molecular-mass IGFI species. Conversion of the primary translation product to the differently glycosylated IGFI precursor proteins and into the mature form occurred very rapidly, within 2 min. Rapid maturation was, however, not followed by an equally rapid secretion of the mature form into the medium: only after 30-40 min did IGFI appear outside the cells. We therefore postulate the presence of an as yet undefined Golgi or post-Golgi bottleneck representing a major obstacle in secretion of recombinant IGFI from S. cerevisiae cells.
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Affiliation(s)
- K Steube
- Biotechnology Department Ciba, Geigy Ltd, Basel, Switzerland
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Bayne M, Applebaum J, Chicchi G, Miller R, Cascieri M. The roles of tyrosines 24, 31, and 60 in the high affinity binding of insulin-like growth factor-I to the type 1 insulin-like growth factor receptor. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(18)55447-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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12
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Affholter JA, Cascieri MA, Bayne ML, Brange J, Casaretto M, Roth RA. Identification of residues in the insulin molecule important for binding to insulin-degrading enzyme. Biochemistry 1990; 29:7727-33. [PMID: 2271531 DOI: 10.1021/bi00485a022] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Insulin-degrading enzyme (IDE) hydrolyzes insulin at a limited number of sites. Although the positions of these cleavages are known, the residues of insulin important in its binding to IDE have not been defined. To this end, we have studied the binding of a variety of insulin analogues to the protease in a solid-phase binding assay using immunoimmobilized IDE. Since IDE binds insulin with 600-fold greater affinity than it does insulin-like growth factor I (25 nM and approximately 16,000 nM, respectively), the first set of analogues studied were hybrid molecules of insulin and IGF I. IGF I mutants [insB1-17,17-70]IGF I, [Tyr55,Gln56]IGF I, and [Phe23,Phe24,Tyr25]IGF I have been synthesized and share the property of having insulin-like amino acids at positions corresponding to primary sites of cleavage of insulin by IDE. Whereas the first two exhibit affinities for IDE similar to that of wild type IGF I, the [Phe23,Phe24,Tyr25]IGF I analogue has a 32-fold greater affinity for the immobilized enzyme. Replacement of Phe-23 by Ser eliminates this increase. Removal of the eight amino acid D-chain region of IGF I (which has been predicted to interfere with binding to the 23-25 region) results in a 25-fold increase in affinity for IDE, confirming the importance of residues 23-25 in the high-affinity recognition of IDE. A similar role for the corresponding (B24-26) residues of insulin is supported by the use of site-directed mutant and semisynthetic insulin analogues. Insulin mutants [B25-Asp]insulin and [B25-His]insulin display 16- and 20-fold decreases in IDE affinity versus wild-type insulin.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J A Affholter
- Department of Pharmacology, Stanford University School of Medicine, California 94305
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Affiliation(s)
- R E Humbel
- Biochemisches Institut, Universität Zürich, Switzerland
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Bayne ML, Applebaum J, Underwood D, Chicchi GG, Green BG, Hayes NS, Cascieri MA. The C Region of Human Insulin-like Growth Factor (IGF) I Is Required for High Affinity Binding to the Type 1 IGF Receptor. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)60418-1] [Citation(s) in RCA: 98] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Cascieri MA, Slater EE, Vicario PP, Green BG, Bayne ML, Saperstein R. Impaired insulin-like growth factor I-mediated stimulation of glucose incorporation into glycogen in vivo in the ob/ob mouse. Diabetologia 1989; 32:342-7. [PMID: 2547681 DOI: 10.1007/bf00277256] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The ability of insulin to modulate glucose metabolism is impaired in insulin resistant ob/ob mice. It has been shown that insulin-like growth factor I stimulates the uptake and metabolism of glucose in muscle through the insulin-like growth factor receptor not the insulin receptor. Thus, we have compared the abilities of insulin-like growth factor I and insulin to stimulate the in vivo incorporation of [14C]-glucose into glycogen in the diaphragm of ob/ob mice and their lean littermates. The animals used in these studies were 12-14 weeks old and the serum insulin levels of the ob/ob mice were 16-fold higher than in their lean littermates. There were no differences in the serum levels of glucose or insulin-like growth factor I. Both insulin and insulin-like growth factor I stimulate the incorporation of [14C]-glucose into glycogen in lean mice. Significant stimulation occurs at doses as low as 1 micrograms/kg of either peptide. The effective doses of insulin and insulin-like growth factor I are quite similar, which indicates that the effect of insulin-like growth factor I is mediated by the insulin-like growth factor receptor and not the insulin receptor. In contrast, greater than 100 micrograms/kg of insulin-like growth factor I is required to stimulate [14C]-glucose incorporation into glycogen in the diaphragm of ob/ob mice. Thus, ob/ob mice are resistant to the action of both insulin and insulin-like growth factor I.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M A Cascieri
- Department of Biochemical Endocrinology, Merck Sharp and Dohme Research Laboratories, Rahway, New Jersey
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Cascieri MA, Hayes NS, Bayne ML. Characterization of the increased biological potency in BALB/C 3T3 cells of two analogs of human insulinlike growth factor I which have reduced affinity for the 28 K cell-derived binding protein. J Cell Physiol 1989; 139:181-8. [PMID: 2708454 DOI: 10.1002/jcp.1041390125] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We have characterized the biological activity of two analogs of insulinlike growth factor I (IGF I) which have significantly reduced affinity for the soluble 28 K binding proteins which are secreted by various cell types. The analogs, which were made by site-directed mutagenesis of a synthetic gene encoding for IGF I, are [Gln 3, Ala 4, Tyr 15, Leu 16] IGF I and an analog in which the first 16 amino acids of IGF I were replaced with the first 17 amino acids of insulin (B-chain mutant). These two peptides have 100-fold and greater than 1,000-fold lower affinity, respectively, than IGF I for the 28 K binding protein present in the conditioned medium of two cell types, the clonal rat vascular smooth muscle line A10, and BALB/C 3T3 cells. The 28 K protein secreted by BALB/C 3T3 cells has fivefold-lower apparent affinity for both IGF I and [Gln 3, Ala 4, Tyr 15, Leu 16] IGF I than does the 28 K protein secreted by A 10 cells. Conditioned medium from these two cell types has similar amounts of unoccupied 28 K protein as evidenced by the ability of 125I-IGF I to specifically bind to and be covalently bound to the protein after treatment with the bifunctional cross-linking reagent disuccinimidyl suberate. In the presence of 0.1% calf serum, IGF I and [Gln 3, Ala 4, Tyr 15, Leu 16] IGF I stimulate DNA synthesis in A10 cells with ED50 = 0.4 nM, and in BALB/C 3T3 cells with ED50 = 10 nM and 1.3 nM, respectively. Thus, these peptides are equipotent in A10 cells, but the mutant peptide is ten times more active than IGF I in BALB/C 3T3 cells. A10 cells can be made ten times less sensitive to IGF I by performing the incubation in the presence of conditioned media from BALB/C 3T3 cells but not from A10 cells. The activity of [Gln 3, Ala 4, Tyr 15, Leu 16] IGF I is not altered under these conditions. Thus, the conditioned media, which contain 28 K proteins secreted by A10 cells and BALB/C 3T3 cells, have different effects on the biological action of IGF I. These data suggest that the 28 K binding proteins can have important effects on the sensitivity of tissues to IGF I and that the B-chain mutant and [Gln 3, Ala 4, Tyr 15, Leu 16] IGF I will be useful in assessing the biological role of these proteins.
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Affiliation(s)
- M A Cascieri
- Department of Biochemical Endocrinology, Merck Sharp and Dohme Research Laboratories, Rahway, New Jersey 07065
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Cascieri MA, Chicchi GG, Applebaum J, Green BG, Hayes NS, Bayne ML. Structural Analogs of Human Insulin-like Growth Factor (IGF) I with Altered Affinity for Type 2 IGF Receptors. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)94162-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Gröger G, Ramalho-Ortigao F, Steil H, Seliger H. A comprehensive list of chemically synthesized genes. Nucleic Acids Res 1988; 16:7763-71. [PMID: 3047671 PMCID: PMC338488 DOI: 10.1093/nar/16.16.7763] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
A databank for chemically synthesized genes has been compiled.
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Affiliation(s)
- G Gröger
- Rechenzentrum für Forschung, Lehre Universität Ulm, FRG
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20
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Structural analogs of human insulin-like growth factor I with reduced affinity for serum binding proteins and the type 2 insulin-like growth factor receptor. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)68777-0] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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21
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Gorewit RC, Chen HY, Kopchick JJ. Growth hormone gene expression in myoepithelial cells directed by various eucaryotic transcriptional regulatory sequences. FEBS Lett 1987; 225:238-42. [PMID: 2826241 DOI: 10.1016/0014-5793(87)81165-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Mammary gland myoepithelial cells were isolated from cattle and cell lines were established. Cells were plated onto tissue culture dishes with or without collagen. Cells were transfected with bovine growth hormone rDNA containing one of the following eucaryotic transcriptional regulatory sequences: human cytomegalovirus immediate early promoter, simian virus 40 early promoter, mouse metallothionein I promoter and the Rous sarcoma virus long terminal repeat. These sequences were evaluated for their ability to direct recombinant bovine growth hormone DNA expression in myoepithelial cells. The most effective transcriptional regulatory sequences were the cytomegalovirus immediate early and simian virus 40 early promoters.
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Affiliation(s)
- R C Gorewit
- Department of Animal Science, Cornell University, Ithaca, NY 14853
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