Abstract
The MUC7 gene encodes the protein core of the low molecular weight human salivary mucin (MG2, mucin glycoprotein 2) and is expressed in a tissue-specific manner in salivary glands. The purpose of this study was to examine MUC7 expression by transgenic mouse technology. A 16 kb DNA fragment, containing the MUC7 gene (10 kb) and 3 kb of the upstream and 3 kb of the downstream sequences, was used to generate transgenic mice. We have identified five transgenic founder mice which were propagated as individual transgenic lines and analysed. Tissues of transgenic offspring from each line were analysed by RT-PCR to determine the sites of the MUC7 expression. The results indicated that only line 3 and line 5 expressed the MUC7 gene in salivary glands. The level of MUC7 expression in selected tissues was then determined by northern blot analyses. The results showed that line 3 mice contained high levels of MUC7 transcripts in the sublingual glands of both males and females and indicated low levels of MUC7 transcripts in the submandibular glands of females. No MUC7 expression was detected in this line by northern blot analysis in any other tissue tested. On the other hand, no expression of MUC7 was detected in any tissues of line 5 mice examined by northern blot analysis. A Southern blot analysis of human and mouse genomic DNA demonstrated multiple copies of the MUC7 transgene in line 3 and a single copy in line 5. Collectively, these results indicate that the regulatory sequences required for the tissue-specific expression of MUC7 are within the MUC7 transgene. However, the sequences necessary for expression comparable to that of MUC7 in human salivary glands may be missing from this construct. Western blot analysis of protein extracts from different tissues of transgenic mice line 3 showed that MUC7 gene product was produced in the submandibular-sublingual gland complex of both male and female mice and not in the other tissues examined
Similar content being viewed by others
References
Biesbrock, A.R., Reddy, M.S. and Levine, M.J. (1991) Interaction of a salivary mucin-secretory immunoglobulin A complex with mucosal pathogens. Infect. Immun. 59, 3492-7.
Biesbrock, A.R., Bobek, L.A. and Levine, M.J. (1997) MUC7 mucin gene expression and genetic polymorphism. Glycoconjugate J., 14, 415-422.
Bobek, L.A., Tsai, H., Biesbrock, A.R. and Levine, M.J. (1993) Molecular cloning, sequence and specificity of expression of the gene encoding the low molecular weight human salivary mucin (MUC7). J. Biol. Chem. 268, 20563-9.
Bobek, L.A., Liu, J., Bobek, Y. and Levine, M.J. (1996) Structure and chromosomal localization of the human salivary mucin gene, MUC7. Genomics 31, 277-82.
Chai, Y., Klauser, D.K., Denny, P.A. and Denny, P.C. (1993) Proliferative and structural differences between male and female mouse submandibular glands. Anatom. Records 235, 303-11.
Chomczynski, P. and Sacchi, N. (1987) Single step RNA isolation by acid guanidinium thiocyanate phenolchlorophorm extraction. Analytical Biochemistry 162, 156-9.
Cohen, R.E., Aguirre, A., Neiders, M.E., Levine, M.J., Jones, P.C., Reddy, M.S. and Haar, J.G. (1991) Immunochemistry and immunogenicity of low molecular-weight human salivary mucin. Arch. Oral Biol. 36, 127-36.
Denny, P.C., Mirels, L. and Denny, P.A. (1996) Mouse submandibular gland salivary apomucin contains repeated N-glycosylation sites. Glycobiology 6, 43-50.
Ebisu, S., Nakae, H., Fukuhara, H. and Okada, H. (1992) The mechanism of Eikenella corrodens aggregation by salivary glycoprotein and the effect of glycoprotein on oral bacterial aggregation. J. Periodontol. Res. 27, 615-22.
Feinberg, A.P. and Vogelstein, B. (1983) A technique for radiolabeling DNA restriction endonuclease fragments to high specific activity. Anal. Biochem. 132, 6-13.
Gallagher, S.R. and Smith, J.A. (1987) Denaturing (SDS) discontinuous gel electrophoresis: Laemmli gel method. In Ausubel, F.M., Brent, R., Kingston, R.E., Moore, D.D., Smith, J.A., Seidman, J.G., Struhl, K. (eds), Current Protocols in Molecular Biology, basic protocol, unit 10.2.4–10.2.6, New York, NY, USA: Greene Publishing Associates, Inc. and John Wiley & Sons, Inc.
Hogan, B., Costantini, F. and Lacy, E. (1986) Manipulating the Mouse Embryo: a Laboratory Manual, Cold Spring Harbor, NY, USA: Cold Spring Harbor Laboratory Press.
Kingston, R.E., Chomczynski, P. and Sacchi, N. (1987) Single-step RNA isolation from cultured cells or tissues. In Ausubel, F.M., Brent, R., Kingston, R.E., Moore, D.D., Smith, J.A., Seidman, J.G., Struhl, K. (eds), Current Protocols in Molecular Biology, alternate protocol, unit 4.2.4–4.2.5, New York, NY, USA: Greene Publishing Associates, Inc. and John Wiley & Sons, Inc.
Kollias, G., Wrighton, N., Hurst, J. and Grosveld, F. (1986) Regulated expression of human Aγ-, β-, and hybrid γβ-globin genes in transgenic mice: manipulation of the developmental expression patterns. Cell 46, 89-94.
Larsen, H.J., Brodersen, C.H. and Hjorth, J.P. (1994) High-level salivary gland expression in transgenic mice. Transgenic Res. 3, 311-6.
Levine, M.J., Herzberg, M.C., Levine, M.S., Ellison, S.A., Stinson, M.W., Li, H.C. and van Dyke, T. (1978) Specificity of salivary-bacterial interactions: role of terminal sialic acid residues in the interaction of salivary glycoproteins with Streptococcus sanguis and Streptococcus mutans. Infect. Immun. 19, 107-15.
Mikkelsen, T.R., Brandt, J., Larsen, H.J., Larsen, B.B., Poulsen, K., Ingerslev, J., Din, N. and Hjorth, J.P. (1992) Tissue-specific expression in the salivary glands of transgenic mice. Nucl. Acids Res. 20, 2249-55.
Mockrin, S.C., Dzau, V.J., Gross, K.W. and Horan, M.J. (1991) Transgenic animals: new approaches to hypertension research. Hypertension 17, 394-9.
Murray, P.A., Levine, M.J., Tabak, L.A. and Reddy, M.S. (1982) Specificity of salivary-bacterial interactions: II. Evidence for a lectin on Streptococcus sanguis with specificity for a NeuAcα2,3Galβ1,3GalNAc sequence. Biochem. Biophys. Res. Commun. 106, 390-6.
Murray, P.A., Prakobphol, A., Lee, T., Hoover, C.I. and Fisher, S.J. (1992) Adherence of oral streptococci to salivary glycoproteins. Infect. Immun. 60, 31-8.
Peat, N., Gendler, S.J., Lalani, E.-N., Duhig, T. and Taylor-Papadimitriou, J. (1992) Tissue-specific expression of human polymorphic epithelial mucin (MUC1) in transgenic mice. Cancer Res. 52, 1954-60.
Reddy, M.S., Bobek, L.A., Haraszthy, G.G., Biesbrock, A.R. and Levine, M.J. (1992) Structural features of the low-molecular weight mass human salivary mucin. Biochem. J. 287, 639-43.
Reddy, M.S., Levine, M.J. and Paranchych, W. (1993) Low-molecular-mass human salivary mucin, MG2: Structure and binding of Pseudomonas aeruginosa. Crit. Rev. Oral Biol. Med. 4, 315-23.
Samuelson, L.C. (1996) Transgenic approaches to salivary gland research. Annu. Rev. Physiol. 58, 209-29.
Sigmund, C.D., Jones, C.A., Jacob, H.J., Ingelfinger, J., Kim, U., Gamble, D., Dzau, V.J. and Gross, K.W. (1991) Pathophysiology of vascular smooth muscle in renin promoter-T-antigen transgenic mice. Am. J. Physiol. 260, 249-57.
Sigmund, C.D., Jones, C.A., Kane, C.M., Wu, C., Lang, J.A. and Gross, K.W. (1992) Regulated tissue-and cell-specific expression of the human renin gene in transgenic mice. Circulation Res. 70, 1070-9.
Swift, G.H., Hammer, R.E., MacDonald, R.J. and Brinster, R.L. (1984) Tissue-specific expression of the rat pancreatic elastase I enhancer gene in transgenic mice. Cell 38, 639-46.
Tabak, L.A., Levine, M.J., Jain, N.K., Bryan, A.R., Cohen, R.E., Monte, L.D., Zawacki, S., Nancollas, G.H., Slomiany, A. and Slomiany, B.L. (1985) Adsorption of human salivary mucin to hydroxyapatite. Arch. Oral Biol. 30, 423-7.
Ting, C.-N., Resenberg, M.P., Snow, C.M., Samuelson, L.C. and Meisler, M.H. (1992) Endogenous retroviral sequences are required for tissue-specific expression of a human amylase gene. Genes Develop. 6, 1457-65.
Zotter, S., Hageman, P.C., Lossnitzer, A., Mooi, W.J. and Hilgers, J. (1988) Tissue and tumor distribution of human polymorphic epithelial mucin. Cancer Rev. 11–12, 55-101.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Bobek, L., Li, H., Rojstaczer, N. et al. Tissue-specific expression of human salivary mucin gene, MUC7, in transgenic mice. Transgenic Res 7, 195–204 (1998). https://doi.org/10.1023/A:1008841013622
Issue Date:
DOI: https://doi.org/10.1023/A:1008841013622