title: The structural gene for alpha-mannosidase-1 in Dictyostellium discoideum.
abstract: We have isolated 4 independent mutations affecting alpha-mannosidase-1, a developmentally regulated activity in Dictyrostelium discoideum. Three of these result in a thermolabile alpha-mannosidase-1 activity. One mutation also affects the substrate affinity (Km) of the activity. In diploids these mutations show a gene dosage effect and are all alleles. The structural gene for alpha-mannosidase-1, as defined by these mutations, defines a new linkage group, linkage group VI. alpha-mammosidase 1 is probably a homopolymer with subunits of 54,000 daltons. We have also mapped two temperature-sensitive-for-growth mutations onto two previously defined linkage groups.
mesh_terms: D003513:Cycloheximide / Q000494:pharmacology; D004023:Dictyostelium / Q000187:drug effects / Q000201:enzymology*; D004171:Diploidy; D004186:Disaccharidases / Q000096:biosynthesis*; D004351:Drug Resistance; D004591:Electrophoresis, Polyacrylamide Gel; D005796:Genes; D005816:Genetic Complementation Test; D008040:Genetic Linkage; D006238:Haploidy; D006358:Hot Temperature; D008361:Mannosidases / Q000096:biosynthesis* / Q000302:isolation & purification; D009154:Mutation; D009235:Myxomycetes / Q000201:enzymology*
chemical_list: D003513:Cycloheximide; D004186:Disaccharidases; D008361:Mannosidases