Isolation of an aggregation-less mutant of Dictyostelium discoideum with the expression of contact site A glycoprotein.
We isolated mutants defective in aggregation (aggregation-less) by mutagenizing the "double-bypass" mutant HG592 of Dictyostelium discoideum as the parental strain. One of the mutants expressed the contact site A glycoprotein with an apparent molecular weight of 80 X 10(3) on the cell surface in the normal developmental stage and retained EDTA-stable cell contact as well as EDTA-sensitive cell contact. However, the mutant failed to aggregate on agar plates with bacteria. This mutant was designated HG700. We could not identify any differences between this mutant and the parental strain in levels of adenylate cyclase or extracellular phosphodiesterase activity, or in its chemotaxis toward cAMP. The mutant had greatly decreased the incorporation of [35S] sulfate into the particulate fractions of the cells starved for 6 h. This suggests that the modification by sulfation may crucially affect the mechanism of cell aggregation.
Yoshida
M
M
Research Institute of Food Science, Kinki University, Higashi-Osaka, Japan.
Iizuka
Y
Y
D000262:Adenylyl Cyclases / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000096:biosynthesis*; D002449:Cell Aggregation; D002633:Chemotaxis; D015169:Colony Count, Microbial; D004023:Dictyostelium / Q000235:genetics / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D005656:Fungal Proteins / Q000096:biosynthesis*; D015151:Immunoblotting; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D008715:Methionine / Q000494:pharmacology; D008970:Molecular Weight; D009154:Mutation; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D015800:Protozoan Proteins
D015815:Cell Adhesion Molecules; D005656:Fungal Proteins; D008562:Membrane Glycoproteins; D015800:Protozoan Proteins; C052291:cell cohesion molecule, Dictyostelium; D008715:Methionine; D010727:Phosphoric Diester Hydrolases; D000262:Adenylyl Cyclases