Sequence analysis of carcinoembryonic antigen: identification of glycosylation sites and homology with the immunoglobulin supergene family.
Proc Natl Acad Sci U S A
; 84(4): 920-4, 1987 Feb.
Article
en En
| MEDLINE
| ID: mdl-3469650
A direct method for the determination of N-linked glycosylation sites in highly glycosylated proteins is described. Carcinoembryonic antigen (CEA) and a nonspecific crossreacting antigen (NCA) were chemically deglycosylated, and peptide maps were prepared by reverse-phase HPLC. The peptides were sequenced on a gas-phase microsequencer, and glycosylation sites were identified as the phenylthiohydantoin derivative of N-acetylglucosaminylasparagine. The sequences were confirmed by fast atom bombardment mass spectrometry. Highly homologous, extended amino-terminal sequences were determined for CEA and two NCAs, NCA-95 and NCA-55. Cysteine-containing sequences for CEA and NCA-95 show up to 95% sequence homology, and the CEA sequences also show internal sequence homologies. A comparison of the CEA sequences with known protein sequences suggests that CEA may be a member of the immunoglobulin supergene family. The protein sequence data have been used to identify a genomic DNA clone for one of the NCA antigens [Thompson, J., Pande, H., Paxton, R. J., Shively, L., Padma, A., Simmer, R. L., Todd, C. W., Riggs, A. D. & Shively, J. E. (1987) Proc. Natl. Acad. Sci. USA, in press] and a cDNA clone for CEA [Zimmermann, W., Ortlieb, B., Friedrich, R. & von Kleist, S. (1987) Proc. Natl. Acad. Sci. USA, in press].
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Secuencia de Bases
/
Antígeno Carcinoembrionario
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Año:
1987
Tipo del documento:
Article
Pais de publicación:
Estados Unidos