Abstract
Sertoli cells synthesize and secrete a transferrin-like protein (testicular transferrin) [Skinner & Griswold (1980) J. Biol. Chem. 255, 1923-1925]. The purpose of the present study was to purify and characterize testicular transferrin and to compare it with serum transferrin. Testicular transferrin was obtained from the medium of cultured rat Sertoli cells, whereas serum transferrin was obtained from rat serum. Both proteins were purified with the use of phenyl-Sepharose hydrophobic chromatography and transferrin immunoaffinity chromatography. The purified proteins were shown to have similar molecular masses (75 000 Da) and amino acid compositions. The pattern of tryptic peptides from testicular and serum transferrin were found to be essentially the same when analysed by reverse-phase high-pressure liquid chromatography. The carbohydrate composition of both transferrins was determined by several colorimetric assays and g.l.c. Testicular transferrin, isolated from cell culture medium, had increased amounts of glucose, galactose and glucosamine. Serum transferrin that was incubated with cell culture medium also had a large amount of associated glucose. The results show that testicular transferrin and serum transferrin are structurally very similar and are possibly products of the same gene expressed in two different tissues, the testis and liver. However, the amount of carbohydrate associated with these two proteins is different.
Full text
PDF







Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Aisen P., Leibman A. Lactoferrin and transferrin: a comparative study. Biochim Biophys Acta. 1972 Feb 29;257(2):314–323. doi: 10.1016/0005-2795(72)90283-8. [DOI] [PubMed] [Google Scholar]
- Aisen P., Listowsky I. Iron transport and storage proteins. Annu Rev Biochem. 1980;49:357–393. doi: 10.1146/annurev.bi.49.070180.002041. [DOI] [PubMed] [Google Scholar]
- Dorrington J. H., Fritz I. B. Cellular localization of 5alpha-reductase and 3alpha-hydroxysteroid dehydrogenase in the seminiferous tubule of the rat testis. Endocrinology. 1975 Apr;96(4):897–889. doi: 10.1210/endo-96-4-879. [DOI] [PubMed] [Google Scholar]
- Hartree E. F. Determination of protein: a modification of the Lowry method that gives a linear photometric response. Anal Biochem. 1972 Aug;48(2):422–427. doi: 10.1016/0003-2697(72)90094-2. [DOI] [PubMed] [Google Scholar]
- Keutmann H. T., Potts J. T., Jr Improved recovery of methionine after acid hydrolysis using mercaptoethanol. Anal Biochem. 1969 May;29(2):175–185. doi: 10.1016/0003-2697(69)90300-5. [DOI] [PubMed] [Google Scholar]
- Kissinger C., Skinner M. K., Griswold M. D. Analysis of Sertoli cell-secreted proteins by two-dimensional gel electrophoresis. Biol Reprod. 1982 Aug;27(1):233–240. doi: 10.1095/biolreprod27.1.233. [DOI] [PubMed] [Google Scholar]
- Kornfeld R. Structure of the oligosaccharides of three glycopeptides from calf thymocyte plasma membranes. Biochemistry. 1978 Apr 18;17(8):1415–1423. doi: 10.1021/bi00601a009. [DOI] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Lee D. C., McKnight G. S., Palmiter R. D. The chicken transferrin gene. Restriction endonuclease analysis of gene sequences in liver and oviduct DNA. J Biol Chem. 1980 Feb 25;255(4):1442–1450. [PubMed] [Google Scholar]
- Livingston D. M. Immunoaffinity chromatography of proteins. Methods Enzymol. 1974;34:723–731. doi: 10.1016/s0076-6879(74)34094-3. [DOI] [PubMed] [Google Scholar]
- McDonald M. J., Shapiro R., Bleichman M., Solway J., Bunn H. F. Glycosylated minor components of human adult hemoglobin. Purification, identification, and partial structural analysis. J Biol Chem. 1978 Apr 10;253(7):2327–2332. [PubMed] [Google Scholar]
- Skinner M. K., Griswold M. D. Secretion of testicular transferrin by cultured Sertoli cells is regulated by hormones and retinoids. Biol Reprod. 1982 Aug;27(1):211–221. doi: 10.1095/biolreprod27.1.211. [DOI] [PubMed] [Google Scholar]
- Spik G., Bayard B., Fournet B., Strecker G., Bouquelet S., Montreuil J. Studies on glycoconjugates. LXIV. Complete structure of two carbohydrate units of human serotransferrin. FEBS Lett. 1975 Feb 15;50(3):296–299. doi: 10.1016/0014-5793(75)80513-8. [DOI] [PubMed] [Google Scholar]
- Thibodeau S. N., Lee D. C., Palmiter R. D. Identical precursors for serum transferrin and egg white conalbumin. J Biol Chem. 1978 Jun 10;253(11):3771–3774. [PubMed] [Google Scholar]
- WILLIAMS J. A comparison of conalbumin and transferrin in the domestic fowl. Biochem J. 1962 May;83:355–364. doi: 10.1042/bj0830355. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Williams J. A comparison of glycopeptides from the ovotransferrin and serum transferrin of the hen. Biochem J. 1968 Jun;108(1):57–67. doi: 10.1042/bj1080057. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wilson R. M., Griswold M. D. Secreted proteins from rat Sertoli cells. Exp Cell Res. 1979 Oct 1;123(1):127–135. doi: 10.1016/0014-4827(79)90429-4. [DOI] [PubMed] [Google Scholar]