Developmentally-regulated cell surface N-linked oligosaccharides participate in intercellular cohesion in Dictyostelium discoideum.
The ability of purified plasma membrane glycoconjugates to inhibit the EDTA-resistant agglutination between aggregation-stage cells of Dictyostelium discoideum has suggested that receptor binding of these glycoconjugates provides a basis for cell-cell cohesion during aggregation. This has been tested by analysis of a series of mutants with different defects in the assembly of N-linked oligosaccharides. Mutant HL241 lacks outer branch components of N-linked oligosaccharides and fails to aggregate or express EDTA-resistant cohesion. HL244 makes unsulphated but otherwise normal N-linked oligosaccharides, generates multiple tips on aggregated cell mounds in some clones, and shows abnormally strong EDTA-resistant cohesion. Two mutants that are temperature-sensitive for complete processing of N-linked oligosaccharides are also temperature-sensitive for expression of both aggregation ability and EDTA-resistant cohesion. A revertant that recovered essentially normal N-linked oligosaccharide processing at the restrictive temperature has also recovered its ability to aggregate and to agglutinate in EDTA.
Henderson
E J
EJ
Department of Biology, Georgetown University, Washington, DC 20057.
Boose
J A
JA
Cooke
S V
SV
Wu
W
W
D000371:Agglutination; D000818:Animals; D002240:Carbohydrate Sequence; D002462:Cell Membrane / Q000502:physiology; D004023:Dictyostelium / Q000502:physiology*; D006017:Glycolipids / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*; D008563:Membrane Lipids / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*
D006017:Glycolipids; D008562:Membrane Glycoproteins; D008563:Membrane Lipids; D009844:Oligosaccharides