Differential expression of an E-selectin ligand (SLex) by two Chinese hamster ovary cell lines transfected with the same alpha (1,3)-fucosyltransferase gene (ELFT).

摘要: The mammalian cDNA encoding alpha (1,3)-fucosyltransferase (alpha (1,3)Fuc-T) termed ELAM-1 ligand fucosyltransferase (ELFT) or Fuc-TIV was previously cloned by three groups who reported different results from transfection studies Goelz et al. (Goelz, S. E., Hession, C., Goff, D., Griffiths, B., Tizard, R., Newman, Chi-Rosso, G., and Lobb, R. (1990) Cell 63, 1349-1356) found that Chinese hamster ovary (CHO) cells expressing the ELFT had (1,3)Fuc-T activity were able to bind E-selectin. In contrast, Lowe (Lowe, J. Kukowska-Latallo, F., Nair, P., Larsen, Marks, M., Macher, B. A., Kelly, J., Ernst, L. K. (1991) Biol. Chem. 266, 17467-17477) Kumar (Kumar, Potvin, Muller, W. Stanley, P. 21777-21783) no binding E-selectin of CHO transfectants same gene; nor did latter synthesize a known ligand, sialylated Lex (SLex), although they substantial activity. We now show these discrepant due difference between parental cell lines. Following into Pro-5 dihydrofolate reductase (DHFR)- cells, only DHFR- expressed SLex bound Indirect evidence monoclonal antibody lectin indicates range carbohydrate structures synthesized lines differs. Since DHFR-/ELFT surface but transferred fucose poorly substrates in vitro, may be fucosylate complex missing cells. Alternatively, either line have an (such as (2,3)-sialyltransferase), modifies (1,3)-fucosylated lactosamines.