The spore coat of a fucosylation mutant in Dictyostelium discoideum.
Strain HL250 of Dictyostelium discoideum cannot convert GDP-mannose to GDP-fucose, resulting in an inability to fucosylate protein. This affects a group of proteins which are normally fucosylated intracellularly and then secreted via prespore vesicles to become part of the outer lamina of the spore coat. We have found that strain HL250 nevertheless accumulates typical amounts of these proteins, stores them normally in prespore vesicles, and secretes them normally to become a part of the spore coat. However, affected proteins are proteolyzed after germination, the spore coat is more accessible to penetration by a macromolecular probe, and germination is inefficient in older spores. These findings can be explained by a dependence of the integrity of the outer layer of the spore coat on protein-linked fucose.
Gonzalez-Yanes
B
B
Department of Anatomy and Cell Biology, College of Medicine, University of Florida, Gainesville 32610-0235.
Mandell
R B
RB
Girard
M
M
Henry
S
S
Aparicio
O
O
Gritzali
M
M
Brown
R D
RD
Erdos
G W
GW
West
C M
CM
D000911:Antibodies, Monoclonal; D015153:Blotting, Western; D002463:Cell Membrane Permeability; D002851:Chromatography, High Pressure Liquid; D004023:Dictyostelium / Q000235:genetics / Q000502:physiology*; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D005456:Fluorescent Dyes; D005643:Fucose / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism; D006031:Glycosylation; D006154:Guanosine Diphosphate Fucose / Q000378:metabolism; D006155:Guanosine Diphosphate Mannose / Q000378:metabolism; D037102:Lectins / Q000378:metabolism; D008970:Molecular Weight; D009154:Mutation; D012235:Rhodamines / Q000378:metabolism; D013172:Spores, Fungal / Q000378:metabolism
D000911:Antibodies, Monoclonal; D005456:Fluorescent Dyes; D005656:Fungal Proteins; D006023:Glycoproteins; D037102:Lectins; D012235:Rhodamines; C060011:TRITC-RCA-I; D006154:Guanosine Diphosphate Fucose; D005643:Fucose; D006155:Guanosine Diphosphate Mannose