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Sadovnikova A, Garcia SC, Hovey RC. A Comparative Review of the Extrinsic and Intrinsic Factors Regulating Lactose Synthesis. J Mammary Gland Biol Neoplasia 2021; 26:197-215. [PMID: 34125363 PMCID: PMC8236052 DOI: 10.1007/s10911-021-09491-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 05/20/2021] [Indexed: 12/31/2022] Open
Abstract
Milk is critical for the survival of all mammalian offspring, where its production by a mammary gland is also positively associated with its lactose concentration. A clearer understanding of the factors that regulate lactose synthesis stands to direct strategies for improving neonatal health while also highlighting opportunities to manipulate and improve milk production and composition. In this review we draw a cross-species comparison of the extra- and intramammary factors that regulate lactose synthesis, with a special focus on humans, dairy animals, and rodents. We outline the various factors known to influence lactose synthesis including diet, hormones, and substrate supply, as well as the intracellular molecular and genetic mechanisms. We also discuss the strengths and limitations of various in vivo and in vitro systems for the study of lactose synthesis, which remains an important research gap.
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Affiliation(s)
- Anna Sadovnikova
- Graduate Group in Nutritional Biology, Physician Scientist Training Program, University of California, Davis, CA, United States.
- Department of Animal Science, University of California, Davis, CA, United States.
| | - Sergio C Garcia
- School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Russell C Hovey
- Department of Animal Science, University of California, Davis, CA, United States
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Abubakar M, Saeed A, Kul O. Modification of Animal Products for Fat and Other Characteristics. THE ROLE OF BIOTECHNOLOGY IN IMPROVEMENT OF LIVESTOCK 2015. [PMCID: PMC7121827 DOI: 10.1007/978-3-662-46789-3_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This chapter includes information about modification of animal products using biotechnology and the importance of different modifications on the natural composition. The species considered for modified products include beef and dairy cattle, sheep, goats, poultry, and a wide variety of fishes. Moreover, the discussion includes the importance of animal food, nongenetically engineered animal modified food products, genetically engineered animal modified food items primarily for meat, milk, or egg and genetically engineered animal food along the transgenic approach for animal welfare. Modern biotechnology can improve productivity, consistency, and quality of alter animal food, fiber, and medical products. The transgenic technology is potentially valuable to alter characters of economic importance in a rapid and precise way. The food safety issue related to genetic engineering is also included in this chapter. The harm of such modified food and transgenic strategy should also be understood by the reader along with its advantages. In this context, transgenic approaches in animal biotechnology are under discussion that ranges from animal food production to their adverse effects.
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Affiliation(s)
| | - Ali Saeed
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Pakistan
| | - Oguz Kul
- Veterinary Faculty, Kirikkale University, Yahsihan, Turkey
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Bodrogi L, Brands R, Raaben W, Seinen W, Baranyi M, Fiechter D, Bosze Z. High Level Expression of Tissue-Nonspecific Alkaline Phosphatase in the Milk of Transgenic Rabbits. Transgenic Res 2006; 15:627-36. [PMID: 16826424 DOI: 10.1007/s11248-006-9015-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Accepted: 05/19/2006] [Indexed: 10/24/2022]
Abstract
Alkaline phosphatase is a promising therapeutic agent in the Gram-negative bacterial lipopolysaccharide (LPS) mediated acute and chronic diseases. Contrary to other alkaline phosphatase isozymes, purified tissue-nonspecific alkaline phosphatase (TNAP) is not available in large quantities from tissue sources, which would enable to analyse its efficacy in animal sepsis models. Two transgenic rabbit lines were created by pronuclear microinjection with the whey acidic protein promoter-humanTNAP minigene (WAP-hTNAP). Lactating females of both lines produced biologically active human TNAP. As indicated by fractionation of milk samples the recombinant alkaline phosphatase was associated with the membrane of milk fat globules. Alkaline phosphatase enzymatic activity was two orders of magnitude higher compared to normal human serum levels. The demonstration that this TNAP is physiologically active would provide the clue to use transgenic animals as bioreactor for bulk production of the human tissue-nonspecific alkaline phosphatase in milk. This may be a valuable and possibly viable option with important implication in attenuating LPS mediated inflammatory responses.
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Affiliation(s)
- L Bodrogi
- Department of Animal Biology, Agricultural Biotechnology Center, P.O.B. 411, H-2100 Gödöllo, Hungary
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Fujiwara Y, Takahashi RI, Hirabayashi M, Ueda M, Muramatsu T, Yamanaka H, Sekikawa K. Analysis of the flanking regions of the human alpha-lactalbumin gene responsible for position-effect independent expression. Gene 2003; 305:71-8. [PMID: 12594043 DOI: 10.1016/s0378-1119(02)01214-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Transgenic rats with the 130 kb bacterial artificial chromosome construct bLA, including the alpha-lactalbumin gene, had position-independent and copy number-dependent expression, which confirmed previous experiments using the 210 kb yeast artificial construct, yLALBA. To identify elements that confer a position effect, we compared the yLALBA and bLA sequences. yLALBA was chimeric. A common 32 kb region was identified and the total nucleotide sequence was determined. We previously analyzed transgenic rats using polymerase chain reaction to compare the integrity and expression of the transgenes. The -6 to +9 kb region is considered to be necessary for position-independent expression. Transgenic rats lacking the -3.4 to -0.85 kb region had a severe position effect. This 2.5 kb region contains two DNaseI hypersensitive sites at -1.0 and -2.8 kb. The 2.5 kb region is proposed to be a locus control region of the human alpha-lactalbumin gene.
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Affiliation(s)
- Yoshihiro Fujiwara
- Division of Immunology, National Institute of Animal Health, Kannondai 3-1-1, Tsukuba, Ibaragi 305-0856, Japan
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Prieto PA, Kopchick JJ, Kelder B. Transgenic animals and nutrition research. J Nutr Biochem 1999; 10:682-95. [PMID: 15539267 DOI: 10.1016/s0955-2863(99)00063-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/1998] [Accepted: 09/10/1999] [Indexed: 10/16/2022]
Abstract
Transgenic animals are useful tools for the study of biological functions of proteins and secondary gene products synthesized by the action of protein catalysts. Research in nutrition and allied fields is benefiting from their use as models to contrast normal and altered metabolism. Although food, nutritional products, and ingredients from transgenic animals have not yet reached consumers, the technologies for their production are maturing and yielding exciting results in experimental and farm animals. Regulatory governmental bodies are already issuing guidelines and legislation in anticipation of the advent of these products and ingredients. This review summarizes available technology for the production of transgenic animals, discusses their scientific and commercial potential, and examines ancillary issues relevant to the field of nutrition.
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Affiliation(s)
- P A Prieto
- Abbott Laboratories, Ross Products Division, Department of Strategic Research and Discovery, Columbus, OH 43215, USA
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Wall R. Biotechnology for the production of modified and innovative animal products: transgenic livestock bioreactors. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0301-6226(99)00030-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Since the initial demonstration in 1982 of profound phenotypic effects stemming from the expression of a single transgene, genetic engineering has revolutionized fundamental biological and biomedical research. The application of transgenic technology to farm animals has held the promise of being able to improve animal agriculture significantly and has resulted in a new industry, i.e., the successful expression of foreign proteins in the mammary gland for the pharmaceutical industry. Work over the last few years in model species (e.g., the mouse) and new technical developments such as cloning have now set the stage for the initial application of transgenic technology for the improvement of farm animals. Major limitations that remain are the lack understanding of which genes we should transfer in order to alter quantitative production traits usefully and the low efficiency of producting transgenic founders. Furthermore, more research is needed concerning the consequences and potential problems arising from the integration of transgenes into populations with varying genetic backgrounds. Recent advances suggest that within the first decade of the 21 st century the first transgenic animals will become available to the livestock industry, with acceptance depending upon their cost versus their potential economic benefit to the producers.
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Affiliation(s)
- J D Murray
- Department of Animal Science, University of California, Davis 95616-8521, USA
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Jeng SY, Bleck GT, Wheeler MB, Jiménez-Flores R. Characterization and partial purification of bovine alpha-lactalbumin and beta-casein produced in milk of transgenic mice. J Dairy Sci 1997; 80:3167-75. [PMID: 9436095 DOI: 10.3168/jds.s0022-0302(97)76288-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Bovine alpha-lactalbumin (alpha-LA) and bovine beta-casein (beta-CN), from milk from transgenic mice were characterized and partially purified using electrophoretic, immunoblotting, and chromatographic methods. The transgenically expressed bovine milk proteins were identified using PAGE or by a combination of preparative isoelectrofocusing followed by Western immunoblotting. The heterologous bovine alpha-IA and bovine beta-CN had molecular masses that were identical to those of those of the native proteins. The estimated expression of the proteins was 1.0 mg/ml of milk for alpha-LA and 3.0 mg/ml for beta-CN. The calcium binding of bovine alpha-LA suggested that the protein produced in murine milk has the same electrophoretic shift as native bovine alpha-LA after the removal of calcium. Nitrogen-linked glycosylation of native and murine synthesized bovine alpha-LA was identified by peptide-N-glycosidase F treatment, and the N-terminal amino acid sequence of HPLC-purified bovine alpha-LA from mouse milk was confirmed to be identical to native bovine alpha-LA. In addition, the phosphorylation of the bovine beta-CN expressed in the milk of transgenic mice was the same as that of native bovine beta-CN, as determined by phosphatase digestion.
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Affiliation(s)
- S Y Jeng
- Department of Food Science and Human Nutrition, University of Illinois, Urbana 61801, USA
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Abstract
Amid the explosion of fundamental knowledge generated from transgenic animal models, a small group of scientists has been producing transgenic livestock with goals of improving animal production efficiency and generating new products. The ability to modify mammary-specific genes provides an opportunity to pursue several distinctly different avenues of research. The objective of the emerging gene "pharming" industry is to produce pharmaceuticals for treating human diseases. It is argued that mammary glands are an ideal site for producing complex bioactive proteins that can be cost effectively harvested and purified. Consequently, during the past decade, approximately a dozen companies have been created to capture the US market for pharmaceuticals produced from transgenic bioreactors estimated at $3 billion annually. Several products produced in this way are now in human clinical trials. Another research direction, which has been widely discussed but has received less attention in the laboratory, is genetic engineering of the bovine mammary gland to alter the composition of milk destined for human consumption. Proposals include increasing or altering endogenous proteins, decreasing fat, and altering milk composition to resemble that of human milk. Initial studies using transgenic mice to investigate the feasibility of enhancing manufacturing properties of milk have been encouraging. The potential profitability of gene "pharming" seems clear, as do the benefits of transgenic cows producing milk that has been optimized for food products. To take full advantage of enhanced milk, it may be desirable to restructure the method by which dairy producers are compensated. However, the cost of producing functional transgenic cattle will remain a severe limitation to realizing the potential of transgenic cattle until inefficiencies of transgenic technology are overcome. These inefficiencies include low rates of gene integration, poor embryo survival, and unpredictable transgene behavior.
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Affiliation(s)
- R J Wall
- Gene Evaluation and Mapping Laboratory, USDA-ARS-Livestock and Poultry Science Institute, Beltsville, MD 20705, USA
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Fujiwara Y, Miwa M, Takahashi R, Hirabayashi M, Suzuki T, Ueda M. Position-independent and high-level expression of human alpha-lactalbumin in the milk of transgenic rats carrying a 210-kb YAC DNA. Mol Reprod Dev 1997; 47:157-63. [PMID: 9136116 DOI: 10.1002/(sici)1098-2795(199706)47:2<157::aid-mrd5>3.0.co;2-l] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The level of expression of transgenes in transgenic animals varies among lines, and is often much lower than that of endogenous genes (position effects). In order to surmount position effects and establish a more efficient production system of transgenic animals producing pharmaceutical proteins in their milk, transgenic rats carrying 210-kb YAC DNA containing the human alpha-lactalbumin gene were produced. Three transgenic lines transmitted the transgene to the next generation. They had one copy of the alpha-lactalbumin gene and secreted human alpha-lactalbumin in their milk at concentrations of 2.0-4.3 mg/ml. No position effect was seen. The transgene was expressed specifically in the mammary gland of the transgenic rats. The 210-kb region is thought to contain all the DNA elements required for proper expression of the human alpha-lactalbumin gene. The YAC carrying the human alpha-lactalbumin gene is a potential vector for the expression of foreign genes in the mammary gland.
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Affiliation(s)
- Y Fujiwara
- YS New Technology Institute, Inc., Tochigi, Japan
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Abstract
The engineering of animals for recombinant protein production has gone beyond the stage of identifying proper regulatory sequences. Efforts are now spent on the generation of transgenic animals that process heterologous proteins more efficiently. Another line of research is the development of strategies aimed at bypassing pronuclear microinjection.
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Affiliation(s)
- Y Echelard
- Genzyme Transgenics Corporation, One Mountain Road, Framingham, MA 01701-9322, USA.
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