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Morin CR, Baeva ME, Hollenberg MD, Brain MC. Milk and multiple sclerosis: A possible link? Mult Scler Relat Disord 2024; 83:105477. [PMID: 38308914 DOI: 10.1016/j.msard.2024.105477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/07/2024] [Accepted: 01/26/2024] [Indexed: 02/05/2024]
Abstract
Despite having been formally defined over 150 years ago, the etiology of multiple sclerosis (MS) is still relatively unknown. However, it is now recognized as a multifactorial disease in which genetics, infection, immune function, and environment play a role. We propose an additional piece to the puzzle: milk. In this review, milk is highlighted as a potential risk factor for MS. We examine the overall correlation between bovine milk consumption and the incidence of MS. We then discuss possible mechanisms that may explain the positive association between milk consumption and the development of MS. For instance, butyrophilin (BTN), a milk glycoprotein, can provide molecular mimicry of myelin oligodendrocyte glycoprotein and induce an autoinflammatory response against myelin. Other milk components such as casein, gangliosides, xanthine oxidase, and saturated fats are also analyzed for their potential involvement in the pathophysiology of MS. Finally, we fit milk alongside other well known risk factors of MS: vitamin D levels, Epstein Barr virus infection, and gut dysbiosis. In conclusion, this review summarizes potential mechanisms linking milk as an underappreciated potential risk factor for the development of MS.
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Affiliation(s)
- Caleb R Morin
- University of Calgary Cumming School of Medicine, Calgary, AB T2N 4N1, Canada
| | | | - Morley D Hollenberg
- Department of Physiology & Pharmacology, University of Calgary Cumming School of Medicine, Calgary, AB T2N 4N1, Canada
| | - Michael C Brain
- Department of Biochemistry and Molecular Biology, University of Calgary Cumming School of Medicine, Calgary, AB T2N 4N1, Canada
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Wan Z, Fei T, Clark S, Wang T. Utilization of dairy beta stream to produce phospholipids products by salt precipitation and solvent fractionation. J AM OIL CHEM SOC 2022. [DOI: 10.1002/aocs.12595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Zifan Wan
- Department of Food Science University of Tennessee Knoxville Tennessee USA
- Animal and Dairy Science University of Wisconsin–Platteville Platteville Wisconsin USA
| | - Tao Fei
- Department of Food Science University of Tennessee Knoxville Tennessee USA
| | - Stephanie Clark
- Department of Food Science and Human Nutrition Iowa State University Ames Iowa USA
| | - Tong Wang
- Department of Food Science University of Tennessee Knoxville Tennessee USA
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Chen L, Fakiola M, Staines K, Butter C, Kaufman J. Functional Alleles of Chicken BG Genes, Members of the Butyrophilin Gene Family, in Peripheral T Cells. Front Immunol 2018; 9:930. [PMID: 29765375 PMCID: PMC5938342 DOI: 10.3389/fimmu.2018.00930] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 04/16/2018] [Indexed: 11/16/2022] Open
Abstract
γδ T cells recognize a wide variety of ligands in mammals, among them members of the butyrophilin (BTN) family. Nothing is known about γδ T cell ligands in chickens, despite there being many such cells in blood and lymphoid tissues, as well as in mucosal surfaces. The major histocompatibility complex (MHC) of chickens was discovered because of polymorphic BG genes, part of the BTN family. All but two BG genes are located in the BG region, oriented head-to-tail so that unequal crossing-over has led to copy number variation (CNV) as well as hybrid (chimeric) genes, making it difficult to identify true alleles. One approach is to examine BG genes expressed in particular cell types, which likely have the same functions in different BG haplotypes and thus can be considered “functional alleles.” We cloned nearly full-length BG transcripts from peripheral T cells of four haplotypes (B2, B15, B19, and B21), and compared them to the BG genes of the B12 haplotype that previously were studied in detail. A dominant BG gene was found in each haplotype, but with significant levels of subdominant transcripts in three haplotypes (B2, B15, and B19). For three haplotypes (B15, B19, and B21), most sequences are closely-related to BG8, BG9, and BG12 from the B12 haplotype. We found that variation in the extracellular immunoglobulin-variable-like (Ig-V) domain is mostly localized to the membrane distal loops but without evidence for selection. However, variation in the cytoplasmic tail composed of many amino acid heptad repeats does appear to be selected (although not obviously localized), consistent with an intriguing clustering of charged and polar residues in an apparent α-helical coiled-coil. By contrast, the dominantly-expressed BG gene in the B2 haplotype is identical to BG13 from the B12 haplotype, and most of the subdominant sequences are from the BG5-BG7-BG11 clade. Moreover, alternative splicing leading to intron read-through results in dramatically truncated cytoplasmic tails, particularly for the dominantly-expressed BG gene of the B2 haplotype. The approach of examining “functional alleles” has yielded interesting data for closely-related genes, but also thrown up unexpected findings for at least one haplotype.
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Affiliation(s)
- Lei Chen
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Michaela Fakiola
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Karen Staines
- Pirbright Institute, Compton, United Kingdom.,School of Life Sciences, University of Lincoln, Lincoln, United Kingdom
| | - Colin Butter
- Pirbright Institute, Compton, United Kingdom.,School of Life Sciences, University of Lincoln, Lincoln, United Kingdom
| | - Jim Kaufman
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom.,Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
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4
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Honvo-Houéto E, Truchet S. Indirect Immunofluorescence on Frozen Sections of Mouse Mammary Gland. J Vis Exp 2015. [PMID: 26650781 DOI: 10.3791/53179] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Indirect immunofluorescence is used to detect and locate proteins of interest in a tissue. The protocol presented here describes a complete and simple method for the immune detection of proteins, the mouse lactating mammary gland being taken as an example. A protocol for the preparation of the tissue samples, especially concerning the dissection of mouse mammary gland, tissue fixation and frozen tissue sectioning, are detailed. A standard protocol to perform indirect immunofluorescence, including an optional antigen retrieval step, is also presented. The observation of the labeled tissue sections as well as image acquisition and post-treatments are also stated. This procedure gives a full overview, from the collection of animal tissue to the cellular localization of a protein. Although this general method can be applied to other tissue samples, it should be adapted to each tissue/primary antibody couple studied.
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Wooding FBP, Sargeant TJ. Immunocytochemical Evidence for Golgi Vesicle Involvement in Milk Fat Globule Secretion. J Histochem Cytochem 2015; 63:943-51. [PMID: 26374828 DOI: 10.1369/0022155415608918] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/03/2015] [Indexed: 12/23/2022] Open
Abstract
The exact mechanism of secretion of the milk fat globule (MFG) from the mammary secretory cell is still controversial. We have previously suggested close involvement of Golgi vesicles in this process. This paper provides direct immunocytochemical evidence that butyrophilin is present in the Golgi stack and vesicles in ovine and caprine mammary glands. We suggest that it is the butyrophilin in the Golgi vesicle membrane that forms the specific association with the adipophilin on the lipid surface in the cytoplasm. Exocytosis of the associated Golgi vesicle will then initiate the process of MFG secretion. Further exocytosis of associated Golgi vesicles will continue and complete the process. Areas of the plasmalemma that have butyrophilin delivered by previous non-lipid associated Golgi exocytoses may also contribute to the process of forming the milk fat globule membrane (MFGM).
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Affiliation(s)
- F B Peter Wooding
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom (FBPW)
| | - Timothy J Sargeant
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom (TJS)
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Novakovic P, Charavaryamath C, Moshynskyy I, Lockerbie B, Kaushik RS, Loewen ME, Kidney BA, Stuart C, Simko E. Evaluation of inhibition of F4ac positive Escherichia coli attachment with xanthine dehydrogenase, butyrophilin, lactadherin and fatty acid binding protein. BMC Vet Res 2015; 11:238. [PMID: 26374102 PMCID: PMC4571123 DOI: 10.1186/s12917-015-0528-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Accepted: 08/04/2015] [Indexed: 12/03/2022] Open
Abstract
Background Neonatal and post-weaning colibacillosis caused by enterotoxigenic E. coli is responsible for substantial economic losses encountered by the pork industry. Intestinal colonization of young piglets by E. coli depends on the efficiency of bacterial attachment to host gastrointestinal epithelium that is mediated by fimbriae. We tested the effect of porcine individual milk fat globule membrane (MFGM) proteins on F4ac positive E. coli attachment to porcine enterocytes in vitro. Results Butyrophilin, lactadherin and fatty acid binding protein inhibited fimbriae-dependent adherence of E. coli to enterocytes in vitro, while xanthine dehydrogenase did not. The inhibiting activity was dose-dependent for all three proteins, but the inhibiting efficiency was different. Conclusions The results indicate that MFGM proteins may interfere with attachment of E. coli to porcine neonatal intestinal mucosa.
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Affiliation(s)
- Predrag Novakovic
- Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
| | - Chandrashekhar Charavaryamath
- Western University of Health Sciences, College of Veterinary Medicine, 309 East Second Street, Pomona, CA, 91766, USA.
| | - Igor Moshynskyy
- Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
| | - Betty Lockerbie
- Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
| | - Radhey S Kaushik
- Biology & Microbiology-Box 2140D, South Dakota State University, Brookings, SD, 57007, USA.
| | - Matthew E Loewen
- Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
| | - Beverly A Kidney
- Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
| | - Chris Stuart
- Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
| | - Elemir Simko
- Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
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O'Riordan N, Kane M, Joshi L, Hickey RM. Structural and functional characteristics of bovine milk protein glycosylation. Glycobiology 2014; 24:220-36. [PMID: 24398766 DOI: 10.1093/glycob/cwt162] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Most secreted and cell membrane proteins in mammals are glycosylated. Many of these glycoproteins are also prevalent in milk and play key roles in the biomodulatory properties of milk and ultimately in determining milk's nutritional quality. Although a significant amount of information exists on the types and roles of free oligosaccharides in milk, very little is known about the glycans associated with milk glycoproteins, in particular, the biological properties that are linked to their presence. The main glycoproteins found in bovine milk are lactoferrin, the immunoglobulins, glycomacropeptide, a glycopeptide derived from κ-casein, and the glycoproteins of the milk fat globule membrane. Here, we review the glycoproteins present in bovine milk, the information currently available on their glycosylation and the biological significance of their oligosaccharide chains.
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Affiliation(s)
- Noelle O'Riordan
- Teagasc Food Research Centre, Moorepark, Fermoy, County Cork, Ireland
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Martini M, Salari F, Altomonte I. The Macrostructure of Milk Lipids: The Fat Globules. Crit Rev Food Sci Nutr 2013; 56:1209-21. [DOI: 10.1080/10408398.2012.758626] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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9
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Kaushik R, Singh KP, Kumari A, Singh MK, Manik RS, Palta P, Singla SK, Chauhan MS. Isolation, characterization, and EGFP expression in the buffalo (Bubalus bubalis) mammary gland epithelial cell line. In Vitro Cell Dev Biol Anim 2012. [PMID: 23180034 DOI: 10.1007/s11626-012-9557-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This study was aimed to establish a buffalo mammary epithelial cells (BuMECs) line and maintain it for long-term by subculturing. BuMECs isolated from lactating buffalo mammary glands were cultured on a collagen matrix gel. BuMECs expressed significant amounts of the epithelial cell specific marker cytokeratin 18 as determined by immunohistochemistry. The BuMECs displayed monolayer, cobble-stone morphology, and formed lumen-, dome-, and duct-like structures. Furthermore, they were capable of synthesizing CSN2, BLG, ACACA, and BTN1A1, showed viability after thawing and expressed milk protein genes. The enhanced green fluorescent protein gene was transferred successfully into the BuMECs using lipofection method and the transfected cells could be maintained for long-term in culture by subculturing.
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Affiliation(s)
- Ramakant Kaushik
- Embryo Biotechnology Lab, Animal Biotechnology Centre, National Dairy Research Institute, Karnal, 132001, India
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10
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Anand V, Dogra N, Singh S, Kumar SN, Jena MK, Malakar D, Dang AK, Mishra BP, Mukhopadhyay TK, Kaushik JK, Mohanty AK. Establishment and characterization of a buffalo (Bubalus bubalis) mammary epithelial cell line. PLoS One 2012; 7:e40469. [PMID: 22792341 PMCID: PMC3392245 DOI: 10.1371/journal.pone.0040469] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 06/08/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The objective of this study was to establish the buffalo mammary epithelial cell line (BuMEC) and characterize its mammary specific functions. METHODOLOGY Buffalo mammary tissue collected from the slaughter house was processed enzymatically to obtain a heterogenous population of cells containing both epithelial and fibroblasts cells. Epithelial cells were purified by selective trypsinization and were grown in a plastic substratum. The purified mammary epithelial cells (MECs) after several passages were characterized for mammary specific functions by immunocytochemistry, RT-PCR and western blot. PRINCIPAL FINDINGS The established buffalo mammary epithelial cell line (BuMEC) exhibited epithelial cell characteristics by immunostaining positively with cytokeratin 18 and negatively with vimentin. The BuMEC maintained the characteristics of its functional differentiation by expression of β-casein, κ-casein, butyrophilin and lactoferrin. BuMEC had normal growth properties and maintained diploid chromosome number (2n = 50) before and after cryopreservation. A spontaneously immortalized buffalo mammary epithelial cell line was established after 20 passages and was continuously subcultured for more than 60 passages without senescence. CONCLUSIONS We have established a buffalo mammary epithelial cell line that can be used as a model system for studying mammary gland functions.
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Affiliation(s)
- Vijay Anand
- National Dairy Research Institute (NDRI), Karnal, India
| | - Nilambra Dogra
- National Centre for Human Genome Studies and Research (NCHGSR), Punjab University, Chandigarh, India
| | | | | | - Manoj K. Jena
- National Dairy Research Institute (NDRI), Karnal, India
| | | | - Ajay K. Dang
- National Dairy Research Institute (NDRI), Karnal, India
| | | | - Tapas K. Mukhopadhyay
- National Centre for Human Genome Studies and Research (NCHGSR), Punjab University, Chandigarh, India
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11
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Chong BM, Reigan P, Mayle-Combs KD, Orlicky DJ, McManaman JL. Determinants of adipophilin function in milk lipid formation and secretion. Trends Endocrinol Metab 2011; 22:211-7. [PMID: 21592818 PMCID: PMC3118920 DOI: 10.1016/j.tem.2011.04.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Revised: 04/02/2011] [Accepted: 04/06/2011] [Indexed: 11/16/2022]
Abstract
In many species the lactating mammary gland is one of the most lipogenic organs of the body. The majority of the lipid produced during lactation is secreted into milk by a novel process of membrane envelopment of cytoplasmic lipid droplets (CLDs). Adipophilin (ADRP/ADPH/PLIN2), a member of the perilipin (PAT) family of lipid droplet proteins, is hypothesized to play a pivotal role in both formation and secretion of milk lipids. Production of milk lipids is the only known example of CLD secretion, and the only process in which PAT family members undergo secretion. This review discusses emerging data on the structural and functional properties of adipophilin that determine its physiological actions and mediate its effects on milk lipid formation and secretion.
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Affiliation(s)
- Brandi M. Chong
- Graduate Program in Molecular Biology, University of Colorado, Anschutz Medical Campus
- Division of Basic Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus
| | - Philip Reigan
- Department of Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus
| | - Kasey D. Mayle-Combs
- University of Colorado Denver Lab Coats Program, University of Colorado, Anschutz Medical Campus
| | - David J. Orlicky
- Department of Pathology, University of Colorado, Anschutz Medical Campus
| | - James L. McManaman
- Graduate Program in Molecular Biology, University of Colorado, Anschutz Medical Campus
- Division of Basic Reproductive Sciences, Department of Obstetrics and Gynecology, University of Colorado, Anschutz Medical Campus
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Argov- Argaman N, Smilowitz JT, Bricarello DA, Barboza M, Lerno L, Froehlich JW, Lee H, Zivkovic AM, Lemay DG, Freeman S, Lebrilla CB, Parikh AN, German JB. Lactosomes: structural and compositional classification of unique nanometer-sized protein lipid particles of human milk. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:11234-42. [PMID: 20925428 PMCID: PMC3039697 DOI: 10.1021/jf102495s] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Milk fat globules (MFGs) are accepted primarily as triacylglycerol delivery systems. The identification of nanometer-sized lipid-protein particles termed "lactosomes" that do not contain triacylglycerol raises the question of their possible functions. MFGs were isolated by slow centrifugation, and lactosomes were isolated by ultracentrifugation at a density equivalent to plasma high-density lipoproteins (HDL) (d > 1.063 g/mL) from human milk obtained from six volunteers at different lactation stages. Isolated lactosomes were analyzed and compared with MFGs for their size distribution, lipidome, proteome, and functional activity. Lactosomes from early milk, day 8, were found to be similar in size as those from mature milk >28 days, averaging ∼ 25 nm in diameter. In total, 97 nonredundant proteins were identified in the MFG and lactosome fractions, 46 of which were unique to the MFG fraction and 29 of which were unique to the lactosome fraction. The proteins identified in the lactosome and MFG fractions were enriched with proteins identified with immunomodulatory pathways. Unlike MFGs and GM1-laden reconstituted HDL that served as a positive control, lactosomal binding capacity to cholera toxin was weak. Lipidomic analyses found that lactosomes were devoid of triacylglycerol and gangliosides, unlike MFGs, but rich in a variety of phospholipid species. The data found differences in structure, composition, and function between lactosomes and MFG, suggesting that these two particles are derived from different biosynthetic and/or secretory pathways. The results reveal a bioactive lipid-protein, nanometer-length scale particle that is secreted into milk not to supply energy to the infant but to play unique, protective, and regulatory roles.
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Affiliation(s)
- Nurit Argov- Argaman
- Department of Animal Science, the Robert H Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, PO Box 12, Rehovot 76100
| | | | | | - Mariana Barboza
- Department of Chemistry, University of California, Davis, CA 95616
| | - Larry Lerno
- Department of Chemistry, University of California, Davis, CA 95616
| | | | - Hyeyoung Lee
- Dept of Food Science and Technology, University of California, Davis, CA 95616
| | - Angela M. Zivkovic
- Dept of Food Science and Technology, University of California, Davis, CA 95616
| | - Danielle G. Lemay
- Dept of Food Science and Technology, University of California, Davis, CA 95616
| | - Samara Freeman
- Dept of Food Science and Technology, University of California, Davis, CA 95616
| | | | - Atul N. Parikh
- Department of Applied Science, University of California, Davis, CA 95616
| | - J. Bruce German
- Dept of Food Science and Technology, University of California, Davis, CA 95616
- Nestle Research Center, Lausanne, Switzerland
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Hu H, Wang J, Bu D, Wei H, Zhou L, Li F, Loor JJ. In vitro culture and characterization of a mammary epithelial cell line from Chinese Holstein dairy cow. PLoS One 2009; 4:e7636. [PMID: 19888476 PMCID: PMC2768788 DOI: 10.1371/journal.pone.0007636] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Accepted: 09/25/2009] [Indexed: 11/18/2022] Open
Abstract
Background The objective of this study was to establish a culture system and elucidate the unique characteristics of a bovine mammary epithelial cell line in vitro. Methodology Mammary tissue from a three year old lactating dairy cow (ca. 100 d relative to parturition) was used as a source of the epithelial cell line, which was cultured in collagen-coated tissue culture dishes. Fibroblasts and epithelial cells successively grew and extended from the culturing mammary tissue at the third day. Pure epithelial cells were obtained by passages culture. Principal Findings The strong positive immunostaining to cytokeratin 18 suggested that the resulting cell line exhibited the specific character of epithelial cells. Epithelial cells cultured in the presence of 10% FBS, supraphysiologic concentrations of insulin, and hydrocortisone maintained a normal diploid chromosome modal number of 2n = 60. Furthermore, they were capable of synthesizing β-casein (CSN2), acetyl-CoA carboxylase-α (ACACA) and butyrophilin (BTN1A1). An important finding was that frozen preservation in a mixture of 90% FBS and 10% DMSO did not influence the growth characteristics, chromosome number, or protein secretion of the isolated epithelial cell line. Conclusions The obtained mammary epithelial cell line had normal morphology, growth characteristics, cytogenetic and secretory characteristics, thus, it might represent an useful tool for studying the function of Chinese Holstein dairy cows mammary epithelial cell (CMECs).
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Affiliation(s)
- Han Hu
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Science, Beijing, China
- Faculty of Animal Science & Technology, Gansu Agricultural University, Lanzhou, China
| | - Jiaqi Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Science, Beijing, China
- * E-mail: (JW); (DB)
| | - Dengpan Bu
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Science, Beijing, China
- * E-mail: (JW); (DB)
| | - Hongyang Wei
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Science, Beijing, China
| | - Linyun Zhou
- State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Science, Beijing, China
| | - Fadi Li
- Faculty of Animal Science & Technology, Gansu Agricultural University, Lanzhou, China
| | - Juan J. Loor
- Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana, Illinois, United States of America
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Evolution of lactation: nutrition v. protection with special reference to five mammalian species. Nutr Res Rev 2009; 21:97-116. [PMID: 19087365 DOI: 10.1017/s0954422408100749] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The evolutionary origin of the mammary gland has been difficult to establish because little knowledge can be gained on the origin of soft tissue organs from fossil evidence. One approach to resolve the origin of lactation has compared the anatomy of existing primitive mammals to skin glands, whilst another has examined the metabolic and molecular synergy between mammary gland development and the innate immune system. We have reviewed the physiology of lactation in five mammalian species with special reference to these theories. In all species, milk fulfils dual functions of providing protection and nutrition to the young and, furthermore, within species the quality and quantity of milk are highly conserved despite maternal malnutrition or illness. There are vast differences in birth weight, milk production, feeding frequency, macronutrient concentration, growth rate and length of lactation between rabbits, quokkas (Setonix brachyurus), pigs, cattle and humans. The components that protect the neonate against infection do so without causing inflammation. Many protective components are not unique to the mammary gland and are shared with the innate immune system. In contrast, many of the macronutrients in milk are unique to the mammary gland, have evolved from components of the innate immune system, and have either retained or developed multiple functions including the provision of nourishment and protection of the hatchling/neonate. Thus, there is a strong argument to suggest that the mammary gland evolved from the inflammatory response; however, the extensive protection that has developed in milk to actively avoid triggering inflammation seems to be a contradiction.
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Menzies KK, Lefèvre C, Macmillan KL, Nicholas KR. Insulin regulates milk protein synthesis at multiple levels in the bovine mammary gland. Funct Integr Genomics 2008; 9:197-217. [PMID: 19107532 DOI: 10.1007/s10142-008-0103-x] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 11/25/2008] [Accepted: 11/25/2008] [Indexed: 01/24/2023]
Abstract
The role of insulin in milk protein synthesis is unresolved in the bovine mammary gland. This study examined the potential role of insulin in the presence of two lactogenic hormones, hydrocortisone and prolactin, in milk protein synthesis. Insulin was shown to stimulate milk protein gene expression, casein synthesis and (14)C-lysine uptake in mammary explants from late pregnant cows. A global assessment of changes in gene expression in mammary explants in response to insulin was undertaken using Affymetrix microarray. The resulting data provided insight into the molecular mechanisms stimulated by insulin and showed that the hormone stimulated the expression of 28 genes directly involved in protein synthesis. These genes included the milk protein transcription factor, ELF5, translation factors, the folate metabolism genes, FOLR1 and MTHFR, as well as several genes encoding enzymes involved in catabolism of essential amino acids and biosynthesis of non-essential amino acids. These data show that insulin is not only essential for milk protein gene expression, but stimulates milk protein synthesis at multiple levels within bovine mammary epithelial cells.
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Affiliation(s)
- Karensa K Menzies
- Department of Zoology, University of Melbourne, Parkville, VIC, Australia.
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Vanderghem C, Blecker C, Danthine S, Deroanne C, Haubruge E, Guillonneau F, De Pauw E, Francis F. Proteome analysis of the bovine milk fat globule: Enhancement of membrane purification. Int Dairy J 2008. [DOI: 10.1016/j.idairyj.2008.02.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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17
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Lisak RP, Benjamins JA, Bealmear B, Yao B, Land S, Nedelkoska L, Skundric D. Differential effects of Th1, monocyte/macrophage and Th2 cytokine mixtures on early gene expression for immune-related molecules by central nervous system mixed glial cell cultures. Mult Scler 2006; 12:149-68. [PMID: 16629418 DOI: 10.1191/135248506ms1251oa] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cytokines secreted within the central nervous system (CNS) are important in the development of multiple sclerosis (MS) lesions. The balance between Th1, monocyte/macrophage (M/M) and Th2 cytokines in the CNS may be pivotal in determining the outcome of lesion development. We examined the effects of mixtures of cytokines on gene expression by CNS glial cells, as mixtures of cytokines are present in MS lesions, which in turn contain mixtures of glial cells. In this initial analysis by gene array, we examined changes at 6 hours to identify early changes in gene expression that represent primary responses to the cytokines. Rat glial cells were incubated with mixtures of Th1, M/M and Th2 cytokines for 6 hours and examined for changes in early gene expression employing microarray gene chip technology. A minimum of 814 genes were differentially regulated by one or more of the cytokine mixtures in comparison to controls, including changes in expression in a large number of genes for immune system-related proteins. Expression of the proteins for these genes likely influences development and inhibition of MS lesions as well as protective and regenerative processes. Analysing gene expression for the effects of various combinations of exogenous cytokines on glial cells in the absence of the confounding effects of inflammatory cells themselves should increase our understanding of cytokine-induced pathways in the CNS.
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Affiliation(s)
- R P Lisak
- Department of Neurology, Wayne State University, Detroit, MI 48201, USA.
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18
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Robenek H, Hofnagel O, Buers I, Lorkowski S, Schnoor M, Robenek MJ, Heid H, Troyer D, Severs NJ. Butyrophilin controls milk fat globule secretion. Proc Natl Acad Sci U S A 2006; 103:10385-10390. [PMID: 16801554 PMCID: PMC1502467 DOI: 10.1073/pnas.0600795103] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The molecular mechanism underlying milk fat globule secretion in mammary epithelial cells ostensibly involves the formation of complexes between plasma membrane butyrophilin and cytosolic xanthine oxidoreductase. These complexes bind adipophilin in the phospholipid monolayer of milk secretory granules, the precursors of milk fat globules, enveloping the nascent fat globules in a layer of plasma membrane and pinching them off the cell. However, using freeze-fracture immunocytochemistry, we find these proteins in locations other than those previously inferred. Significantly, butyrophilin in the residual plasma membrane of the fat globule envelope is concentrated in a network of ridges that are tightly apposed to the monolayer derived from the secretory granule, and the ridges coincide with butyrophilin labeling in the globule monolayer. Therefore, we propose that milk fat globule secretion is controlled by interactions between plasma membrane butyrophilin and butyrophilin in the secretory granule phospholipid monolayer rather than binding of butyrophilin-xanthine oxidoreductase complexes to secretory granule adipophilin.
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Affiliation(s)
- Horst Robenek
- *Leibniz-Institute for Arteriosclerosis Research, University of Münster, 48149 Münster, Germany;
| | - Oliver Hofnagel
- *Leibniz-Institute for Arteriosclerosis Research, University of Münster, 48149 Münster, Germany
| | - Insa Buers
- *Leibniz-Institute for Arteriosclerosis Research, University of Münster, 48149 Münster, Germany
| | - Stefan Lorkowski
- *Leibniz-Institute for Arteriosclerosis Research, University of Münster, 48149 Münster, Germany
| | - Michael Schnoor
- *Leibniz-Institute for Arteriosclerosis Research, University of Münster, 48149 Münster, Germany
| | - Mirko J Robenek
- *Leibniz-Institute for Arteriosclerosis Research, University of Münster, 48149 Münster, Germany
| | - Hans Heid
- Division of Cell Biology, German Cancer Research Center, 69120 Heidelberg, Germany; and
| | - David Troyer
- *Leibniz-Institute for Arteriosclerosis Research, University of Münster, 48149 Münster, Germany
| | - Nicholas J Severs
- National Heart and Lung Institute, Imperial College, London SW3 6LY, United Kingdom
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19
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Singh H. The milk fat globule membrane—A biophysical system for food applications. Curr Opin Colloid Interface Sci 2006. [DOI: 10.1016/j.cocis.2005.11.002] [Citation(s) in RCA: 196] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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20
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Abstract
The cream or fat fraction of milk consists of fat droplets composed primarily of triacylglycerols that are surrounded by cellular membranes. In this review we discuss what is known about how these droplets are formed in and secreted by mammary epithelial cells during lactation. This secretion mechanism, which appears to be unique, is unlike the exocytotic mechanism used by other cell types to secrete lipids. Milk fat globules originate as small, triacylglycerol-rich, droplets that are formed on or in endoplasmic reticulum membranes. These droplets are released from endoplasmic reticulum into the cytosol as microlipid droplets coated by proteins and polar lipids. Microlipid droplets can fuse with each other to form larger cytoplasmic lipid droplets. Droplets of all sizes appear to be unidirectionally transported to apical cell regions by as yet unknown mechanisms that may involve cytoskeletal elements. These lipid droplets appear to be secreted from the cell in which they were formed by being progressively enveloped in differentiated regions of apical plasma membrane. While plasma membrane envelopment appears to be the primary mechanism by which lipid droplets are released from the cell, a mechanism involving exocytosis of lipid droplets from cytoplasmic vacuoles also has been described. As discussed herein, while we have a general overview of the steps leading to the fat globules of milk, virtually nothing is known about the molecular mechanisms involved in milk fat globule formation, intracellular transit, and secretion.
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Affiliation(s)
- Hans W Heid
- Division of Cell Biology, German Cancer Research Center, D-69120 Heidelberg, Germany
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21
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Carreno BM, Collins M. The B7 family of ligands and its receptors: new pathways for costimulation and inhibition of immune responses. Annu Rev Immunol 2002; 20:29-53. [PMID: 11861596 DOI: 10.1146/annurev.immunol.20.091101.091806] [Citation(s) in RCA: 617] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
T cell activation is dependent upon signals delivered through the antigen-specific T cell receptor and accessory receptors on the T cell. A primary costimulatory signal is delivered through the CD28 receptor after engagement of its ligands, B7-1 (CD80) or B7-2 (CD86). Engagement of CTLA-4 (CD152) by the same B7-1 or B7-2 ligands results in attenuation of T cells responses. Recently, molecular homologs of CD28 and CTLA-4 receptors and their B7-like ligands have been identified. ICOS is a CD28-like costimulatory receptor with a unique B7-like ligand. PD-1 is an inhibitory receptor, with two B7-like ligands. Additional members of B7 and CD28 gene families have been proposed. Integration of signals through this family of costimulatory and inhibitory receptors and their ligands is critical for activation of immune responses and tolerance. Understanding these pathways will allow development of new strategies for therapeutic intervention in immune-mediated diseases.
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Affiliation(s)
- Beatriz M Carreno
- Genetics Institute/Wyeth Research, 87 Cambridge Park Drive, Cambridge, Massachusetts 02140, USA.
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22
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Oshima K, Aoki N, Kato T, Kitajima K, Matsuda T. Secretion of a peripheral membrane protein, MFG-E8, as a complex with membrane vesicles. EUROPEAN JOURNAL OF BIOCHEMISTRY 2002; 269:1209-18. [PMID: 11856354 DOI: 10.1046/j.1432-1033.2002.02758.x] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
MFG-E8 (milk fat globule-EGF factor 8) is a peripheral membrane glycoprotein, which is expressed abundantly in lactating mammary glands and is secreted in association with fat globules. This protein consists of two-repeated EGF-like domains, a mucin-like domain and two-repeated discoidin-like domains (C-domains), and contains an integrin-binding motif (RGD sequence) in the EGF-like domain. To clarify the role of each domain on the peripheral association with the cell membrane, several domain-deletion mutants of MFG-E8 were expressed in COS-7 cells. The immunofluorescent staining of intracellular and cell-surface proteins and biochemical analyses of cell-surface-biotinylated and secreted proteins demonstrated that both of the two C-domains were required for the membrane association. During the course of these studies for domain functions, MFG-E8, but not C-domain deletion mutants, was shown to be secreted as membrane vesicle complexes. By size-exclusion chromatography and ultracentrifugation analyses, the complexes were characterized to have a high-molecular mass, low density and higher sedimentation velocity and to be detergent-sensitive. Not only such a exogenously expressed MFG-E8 but also that endogenously expressed in a mammary epithelial cell line, COMMA-1D, was secreted as the membrane vesicle-like complex. Scanning electron microscopic analyses revealed that MFG-E8 was secreted into the culture medium in association with small membrane vesicles with a size from 100 to 200 nm in diameter. Furthermore, the expression of MFG-E8 increased the number of these membrane vesicle secreted into the culture medium. These results suggest a possible role of MFG-E8 in the membrane vesicle secretion, such as budding or shedding of plasma membrane (microvesicles) and exocytosis of endocytic multivesicular bodies (exosomes).
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Affiliation(s)
- Kenji Oshima
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
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23
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24
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Iglesias A, Bauer J, Litzenburger T, Schubart A, Linington C. T- and B-cell responses to myelin oligodendrocyte glycoprotein in experimental autoimmune encephalomyelitis and multiple sclerosis. Glia 2001; 36:220-34. [PMID: 11596130 DOI: 10.1002/glia.1111] [Citation(s) in RCA: 211] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The identification of myelin oligodendrocyte glycoprotein (MOG) as a target for autoantibody-mediated demyelination in experimental autoimmune encephalomyelitis (EAE) resulted in the re-evaluation of the role of B cell responses to myelin autoantigens in the immunopathogenesis of multiple sclerosis. MOG is a central nervous system specific myelin glycoprotein that is expressed preferentially on the outermost surface of the myelin sheath. Although MOG is only a minor component of CNS myelin it is highly immunogenic, inducing severe EAE in both rodents and primates. In rat and marmoset models of MOG-induced EAE demyelination is antibody-dependent and reproduces the immunopathology seen in many cases of MS. In contrast, in mice inflammation in the CNS can result in demyelination in the absence of a MOG-specific B cell response, although if present this will enhance disease severity and demyelination. Clinical studies indicate that autoimmune responses to MOG are enhanced in many CNS diseases and implicate MOG-specific B cell responses in the immunopathogenesis of multiple sclerosis. This review provides a summary of our current understanding of MOG as a target autoantigen in EAE and MS, and addresses the crucial question as to how immune tolerance to MOG may be maintained in the healthy individual.
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Affiliation(s)
- A Iglesias
- Department of Neuroimmunology, Max-Planck-Institute of Neurobiology, Martinsried, Germany
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25
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Abstract
The characteristics and possible functions of the most abundant proteins associated with the bovine milk-fat globule membrane are reviewed. Under the auspices of the Milk Protein Nomenclature Committee of the ADSA, a revised nomenclature for the major membrane proteins is proposed and discussed in relation to earlier schemes. We recommend that proteins be assigned specific names as they are identified by molecular cloning and sequencing techniques. The practice of identifying proteins according to their Mr, electrophoretic mobility, or staining characteristics should be discontinued, except for uncharacterized proteins. The properties and amino acid sequences of the following proteins are discussed in detail: MUC1, xanthine dehydrogenase/oxidase, CD36, butyrophilin, adipophilin, periodic acid Schiff 6/7 (PAS 6/7), and fatty acid binding protein. In addition, a compilation of less abundant proteins associated with the bovine milk-fat globule membrane is presented.
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Affiliation(s)
- I H Mather
- Department of Animal and Avian Sciences, University of Maryland, College Park 20742, USA.
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26
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Cainarca S, Messali S, Ballabio A, Meroni G. Functional characterization of the Opitz syndrome gene product (midin): evidence for homodimerization and association with microtubules throughout the cell cycle. Hum Mol Genet 1999; 8:1387-96. [PMID: 10400985 DOI: 10.1093/hmg/8.8.1387] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Opitz syndrome (OS) is a multiple congenital anomaly manifested by abnormal closure of midline structures. The gene responsible for the X-linked form of this disease, MID1, encodes a protein (midin) that contains a RING, two B-boxes, a coiled-coil (the so-called tripartite motif) and an RFP-like domain. The tripartite motif is characteristic of a family of proteins, named the B-box family, involved in cell proliferation and development. Since the subcellular compartmentalization and the ability to form multiprotein structures both appear to be crucial for the function of this family of proteins, we have studied these properties on the wild-type and mutated forms of midin. We found that endogenous midin is associated with microtubules throughout the cell cycle, co-localizing with cytoplasmic fibres in interphase and with the mitotic spindle and midbodies during mitosis and cytokinesis. Immunoprecipitation experiments demonstrated the ability of the tripartite motif to mediate midin homodimerization, consistent with the evidence, obtained by gel filtration analysis, that midin exists in the form of large protein complexes. Functional characterization of altered forms of midin, resulting from mutations found in OS patients, revealed that association with microtubules is compromised, while the ability to homodimerize and form multiprotein complexes is retained. We suggest that midin is involved in the formation of multiprotein structures acting as anchor points to microtubules and that impaired association with these cytoskeletal structures causes OS developmental defects.
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Affiliation(s)
- S Cainarca
- Telethon Institute of Genetics and Medicine (TIGEM), San Raffaele Biomedical Science Park, Via Olgettina 58, Milan, Italy
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27
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Dawkins R, Leelayuwat C, Gaudieri S, Tay G, Hui J, Cattley S, Martinez P, Kulski J. Genomics of the major histocompatibility complex: haplotypes, duplication, retroviruses and disease. Immunol Rev 1999; 167:275-304. [PMID: 10319268 DOI: 10.1111/j.1600-065x.1999.tb01399.x] [Citation(s) in RCA: 228] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The genomic region encompassing the Major Histocompatibility Complex (MHC) contains polymorphic frozen blocks which have developed by local imperfect sequential duplication associated with insertion and deletion (indels). In the alpha block surrounding HLA-A, there are ten duplication units or beads on the 62.1 ancestral haplotype. Each bead contains or contained sequences representing Class I, PERB11 (MHC Class I chain related (MIC) and human endogenous retrovirus (HERV) 16. Here we consider explanations for co-occurrence of genomic polymorphism, duplication and HERVs and we ask how these features encode susceptibility to numerous and very diverse diseases. Ancestral haplotypes differ in their copy number and indels in addition to their coding regions. Disease susceptibility could be a function of all of these differences. We propose a model of the evolution of the human MHC. Population-specific integration of retroviral sequences could explain rapid diversification through duplication and differential disease susceptibility. If HERV sequences can be protective, there are exciting prospects for manipulation. In the meanwhile, it will be necessary to understand the function of MHC genes such as PERB11 (MIC) and many others discovered by genomic sequencing.
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Affiliation(s)
- R Dawkins
- Centre for Molecular Immunology and Instrumentation, University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands, Australia.
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28
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Abstract
Myelin oligodendrocyte glycoprotein (MOG) is a quantitatively minor component of CNS myelin whose function remains relatively unknown. As MOG is an autoantigen capable of producing a demyelinating multiple sclerosis-like disease in mice and rats, much of the research directed toward MOG has been immunological in nature. Although the function of MOG is yet to be elucidated, there is now a relatively large amount of biochemical and molecular data relating to MOG. Here we summarize this information and include our recent findings pertaining to the cloning of the marsupial MOG gene. On the basis of this knowledge we suggest three possible functions for MOG: (a) a cellular adhesive molecule, (b) a regulator of oligodendrocyte microtubule stability, and (c) a mediator of interactions between myelin and the immune system, in particular, the complement cascade. Given that antibodies to MOG and to the myelin-specific glycolipid galactocerebroside (Gal-C) both activate the same signaling pathway leading to MBP degradation, we propose that there is a direct interaction between the membrane-associated regions of MOG and Gal-C. Such an interaction may have important consequences regarding the membrane topology and function of both molecules. Finally, we examine how polymorphisms and/or mutations to the MOG gene could contribute to the pathogenesis of multiple sclerosis.
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Affiliation(s)
- T G Johns
- Neuroimmunology Laboratory, LaTrobe University, Bundoora, Victoria, Australia
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29
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Deyrup-Olsen I, Luchtel DL. Secretion of mucous granules and other membrane-bound structures: a look beyond exocytosis. INTERNATIONAL REVIEW OF CYTOLOGY 1998; 183:95-141. [PMID: 9666566 DOI: 10.1016/s0074-7696(08)60143-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The substances that animals secrete at epithelial surfaces include not only small molecules and ions delivered by exocytosis, but also a wide variety of materials in membrane-bound form. The latter include mucous granules of pulmonate molluscs, milk fat globules, and products of apocrine and holocrine secretion. Contents include hydrophobic entities (e.g., lipids, hydrocarbons), protective substances (e.g., mucus), and potentially injurious substances (e.g., digestive enzymes, toxins). In some cases vesicles or granules perform significant functions through enzymatic or other properties of the membrane itself (e.g., mammalian prostasome). Much work is still needed to elucidate the ways in which cells release membrane-bound products and how these products are deployed. The current concentration of research effort on exocytosis as a secretory modus should not divert attention from the remarkable versatility of epithelial cells that are capable of utilizing a variety of ways besides exocytosis to transfer materials and information to the external environment.
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Affiliation(s)
- I Deyrup-Olsen
- Department of Zoology, University of Washington, Seattle 98195, USA
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30
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Banghart LR, Chamberlain CW, Velarde J, Korobko IV, Ogg SL, Jack LJ, Vakharia VN, Mather IH. Butyrophilin is expressed in mammary epithelial cells from a single-sized messenger RNA as a type I membrane glycoprotein. J Biol Chem 1998; 273:4171-9. [PMID: 9461613 DOI: 10.1074/jbc.273.7.4171] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
We investigated the expression of butyrophilin in eukaryotic cells with a view to determining the number of mRNA species, the incorporation of the peptide chain into microsomes, and the topology of the processed protein in biological membranes. Butyrophilin is synthesized from a single sized mRNA in both bovine and murine lactating mammary tissue and associates with microsomal membranes with a type I topology (Nexo.Ccyto) via a single hydrophobic anchor in the middle of the sequence. Several isoelectric variants of the protein were detected in cellular membranes from lactating bovine mammary tissue and in the milk-fat-globule membrane. We found no evidence for soluble forms of butyrophilin in postmicrosomal supernatants. The 66-kDa protein appears to be subjected to limited proteolysis, giving rise to a 62-kDa fragment lacking the C terminus and to other more minor fragments of lower Mr in the milk-fat-globule membrane. Antipeptide antibodies to epitopes within the N- and C-terminal domains were used to show that butyrophilin retains a type I topology in plasma membranes when expressed in insect cells from a baculovirus vector, and in secreted milk-fat globules. These data do not agree with previous suggestions that butyrophilin may exist in cytoplasmic soluble forms, or be reorganized in the plane of the lipid bilayer during secretion in lipid droplets from mammary cells. The results are discussed with reference to the role butyrophilin may play as the principal scaffold for the assembly of a complex with xanthine oxidase and other proteins that functions in the budding and release of milk-fat globules from the apical surface during lactation.
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Affiliation(s)
- L R Banghart
- Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland 20742, USA
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31
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Quaderi NA, Schweiger S, Gaudenz K, Franco B, Rugarli EI, Berger W, Feldman GJ, Volta M, Andolfi G, Gilgenkrantz S, Marion RW, Hennekam RC, Opitz JM, Muenke M, Ropers HH, Ballabio A. Opitz G/BBB syndrome, a defect of midline development, is due to mutations in a new RING finger gene on Xp22. Nat Genet 1997; 17:285-91. [PMID: 9354791 DOI: 10.1038/ng1197-285] [Citation(s) in RCA: 257] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Opitz syndrome (OS) is an inherited disorder characterized by midline defects including hypertelorism, hypospadias, lip-palate-laryngotracheal clefts and imperforate anus. We have identified a new gene on Xp22, MID1 (Midline 1), which is disrupted in an OS patient carrying an X-chromosome inversion and is also mutated in several OS families. MID1 encodes a member of the B-box family of proteins, which contain protein-protein interaction domains, including a RING finger, and are implicated in fundamental processes such as body axis patterning and control of cell proliferation. The association of MID1 with OS suggests an important role for this gene in midline development.
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Affiliation(s)
- N A Quaderi
- Telethon Institute of Genetics and Medicine (TIGEM), Milan, Italy
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32
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Studies on the susceptibility of membrane-derived proteins to proteolysis as related to changes in their emulsifying properties. Food Res Int 1997. [DOI: 10.1016/s0963-9969(98)00018-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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33
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Davey HW, Ogg SL, Husaini Y, Snell RG, Korobko IV, Mather IH, Wilkins RJ. Structure and sequence of the bovine butyrophilin gene. Gene X 1997; 199:57-62. [PMID: 9358039 DOI: 10.1016/s0378-1119(97)00346-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The complete sequence of the bovine butyrophilin gene (BTN) is described and compared with the mouse gene (Btn). Both genes contain seven exons separated by six introns, and the organisation of exons is closely associated with structural domains of the protein. Individual exons of BTN and Btn are 68-87% similar in sequence. There are no canonical TATA or CCAAT boxes associated with the transcription initiation sites in the genes of either species. However, a number of potential binding sites for transcription factors were identified in the 5'-flanking DNA, some of which may function in regulating expression of the gene in mammary tissue. Conservation of a 110-bp region in the promoters of BTN and Btn may have some functional significance. Cloning and sequencing of BTN provides an additional mammary-specific gene promoter that may be used for driving the expression of transgenes in the lactating mammary gland, and for determining the basis for tissue-specific gene expression. In addition, the sequence of BTN may be used to map intragenic polymorphisms and identify quantitative trait loci in commercial livestock.
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Affiliation(s)
- H W Davey
- AgResearch, Ruakura Research Centre, Hamilton, New Zealand.
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34
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Barber MC, Clegg RA, Travers MT, Vernon RG. Lipid metabolism in the lactating mammary gland. BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1347:101-26. [PMID: 9295156 DOI: 10.1016/s0005-2760(97)00079-9] [Citation(s) in RCA: 188] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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35
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36
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Heid HW, Schnölzer M, Keenan TW. Adipocyte differentiation-related protein is secreted into milk as a constituent of milk lipid globule membrane. Biochem J 1996; 320 ( Pt 3):1025-30. [PMID: 9003395 PMCID: PMC1218030 DOI: 10.1042/bj3201025] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Milk lipid globules from humans, cows and rats contained a protein identified as adipocyte differentiation-related protein (ADRP) associated with the globule surface membrane material. This protein, previously believed to be specific to adipocytes, was a major constituent of the globule surface and was present in a detergent-insoluble complex that contained stoichiometric amounts of butyrophilin and xanthine oxidase. Identification of ADRP was by sequence similarity of tryptic peptides from cow and human proteins with the sequence inferred from the cDNA for mouse ADRP. The putative ADRP of lipid globules from cow, human and rat milk was recognized specifically by antisera raised against a peptide synthesized to duplicate the N-terminal 26 residues of the mouse protein. In homogenates of lactating mammary gland, ADRP was found only in endoplasmic reticulum and in lipid droplet fractions. ADRP was modified, apparently post-translationally, and one modification apparently was acylation, primarily with C14, C16 and C18 fatty acids. Two isoelectric variants of ADRP were present in cow globule membrane material. In vitro, ADRP served as a substrate for protein kinases associated with milk lipid globule membrane, but this protein did not seem to become phosphorylated intracellularly.
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Affiliation(s)
- H W Heid
- Division of Cell Biology, German Cancer Research Center, Heidelberg, Federal Republic of Germany
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37
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Ogg SL, Komaragiri MV, Mather IH. Structural organization and mammary-specific expression of the butyrophilin gene. Mamm Genome 1996; 7:900-5. [PMID: 8995761 DOI: 10.1007/s003359900265] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Butyrophilin is a glycoprotein of the immunoglobulin superfamily that is secreted in association with the milk-fat-globule membrane from mammary epithelial cells. As a first step towards determining the possible function(s) of this protein in lactation, the mouse butyrophilin gene (Btn) has been cloned from a 129-ES cell genomic library. Over 14 kb of DNA was sequenced, including the entire transcriptional unit of the gene, and 4.6 kb and 1.1 kb of the 5' and 3' flanking region, respectively. In addition, the overall structure of the bovine gene (BTN) was determined by amplification of genomic DNA by the polymerase chain reaction. Both Btn and BTN comprise seven exons and six introns. The signal sequence and two immunoglobulin-like folds of the exoplasmic domain and the membrane anchor are encoded by separate exons, and the cytoplasmic domain is encoded by two short exons and a large terminal exon that also includes 3' untranslated sequence. The butyrophilin gene appears to have evolved from a subset of genes in the immunoglobulin superfamily and genes encoding the B30.2 domain, which is conserved in a family of zinc-finger proteins. Murine butyrophilin mRNA was detected specifically in the mammary gland by RNase protection analysis. Expression increased during the last half of pregnancy and was maximal during lactation. The 5' flanking region of Btn was analyzed for putative regulatory elements and is different from the promoters of other mammary-specific genes. Btn should be useful for determining the mechanisms underlying mammary-specific gene expression and potentially for the production of heterologous proteins in the milk of transgenic animals.
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Affiliation(s)
- S L Ogg
- Department of Animal Sciences, University of Maryland, College Park 20742, USA
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38
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Brunner RM, Guérin G, Goldammer T, Seyfert H, Schwerin M. The bovine butyrophilin encoding gene (BTN) maps to chromosome 23. Mamm Genome 1996; 7:635-6. [PMID: 8678998 DOI: 10.1007/s003359900193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- R M Brunner
- Forschungsbereich Molekularbiologie, Institut für die Biologie landwirtschaftlicher Nutztiere, 18196 Dummerstorf, Germany
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Abstract
Chromosomal assignment of the bovine butyrophilin gene (BTN) was performed by analysis of DNA from somatic hybrid cell lines using the polymerase chain reaction. The gene was assigned to bovine chromosome 23 using two sets of primers specific for bovine BTN.
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Affiliation(s)
- M S Ashwell
- Gene Evaluation and Mapping Laboratory, USDA, ARS, Beltsville, MD 20705, USA
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Taylor MR, Peterson JA, Ceriani RL, Couto JR. Cloning and sequence analysis of human butyrophilin reveals a potential receptor function. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1306:1-4. [PMID: 8611614 DOI: 10.1016/0167-4781(19)60000-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Human butyrophilin was cloned and sequenced from a human breast cDNA library. The derived amino acid sequence shows 84% sequence identity and identical domain arrangements with the previously reported bovine sequence. Sequence analysis reveals an immunoglobulin constant (IgC) domain that was not previously identified in the bovine sequence. The extracellular domain composition of butyrophilin suggests a cell surface receptor function.
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Affiliation(s)
- M R Taylor
- Cancer Research Fund of Contra Costa, Walnut Creek CA 94596, USA
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41
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Expression of the butyrophilin gene, a milk fat globule membrane protein, is associated with the expression of the αS1casein gene. ACTA ACUST UNITED AC 1995. [DOI: 10.1007/bf02389025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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