Polysialic acid in human neuroblastoma cells

Conference · Fri May 01 04:00:00 EDT 1987 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5904426

Livingston, B D; Jacobs, J; Shaw, G W; Glick, M C; Troy, F A

Prokaryotic-derived probes that specifically detect ..cap alpha..-2,8-linked polysialic acid (PSA) units on embryonic neural cell adhesion molecules (N-CAM) were used to show that membrane glycoproteins (GPs) from metastatic human neuroblastoma cells (CHP-134) also contain these unique carbohydrate moieties. This conclusion was based on the following evidence: (1) membranes from CHP-134 cells served as an exogenous acceptor of (/sup 14/C)NeuNAc units in an E. coli K1 sialyltransferase (ST) assay. The bacterial ST is specific for the transfer of (/sup 14/C)NeuNAc to exogenous acceptors containing at least 3 sialyl units (DP3); (2) in SDS-PAGE, the (/sup 14/C)NeuNAc-labeled CHP-134 membranes showed a major peak of radioactivity that was polydisperse. N-CAM shows a similar Mr heterogeneity; (3) treatment of the high Mr CHP-134 product with Endo-N-acetylneuraminidase (Endo-N) released the (/sup 14/C)NeuNAc label as a DP4. Endo-N is specific for hydrolysing ..cap alpha..-2,8-linked PSA chains containing a minimum of 5 sialyl residues; (4) treatment of the DP4 with sialidase converted the label to (/sup 14/C)NeuNAc, thus proving the tetramer contained sialic acid; (5) CHP-134 cells were labeled in vivo with (/sup 3/H)GlcN. A glycopeptide fraction representing ca. 1% of the (/sup 3/H)GlcN incorporated was isolated. Based on Endo-N sensitivity, this glycopeptide contained at least 15-20% of the (/sup 3/H)GlcN label as PSA. Endo-N digestion of the (/sup 3/H)-labeled glycopeptide released (/sup 3/H)-DP4. These results suggest that the surface expression of PSA-containing GPs may be important in neuroblastoma metastasis.

• Research Organization: Univ. of California Medical School, Davis
• OSTI ID: 5904426
• Report Number(s): CONF-870644-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 46:6
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
550901 -- Pathology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANIMALS
CARBOHYDRATES
CARBON 14 COMPOUNDS
CELL CONSTITUENTS
CELL MEMBRANES
CHEMICAL PROPERTIES
ELECTROPHORESIS
GLUCOPROTEINS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
MAN
MEMBRANES
METASTASES
MONOSACCHARIDES
NERVE CELLS
ORGANIC COMPOUNDS
PRIMATES
PROTEINS
SACCHARIDES
SECRETION
SIALIC ACID
SOMATIC CELLS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
TUMOR CELLS
VERTEBRATES