title: Intercellular signaling is required for developmental gene expression in Myxococcus xanthus.
abstract: Certain developmental mutants of Myxococcus xanthus can be complemented (extracellularly) by wild-type cells. Insertions of Tn5 lac (a transposon which couples beta-galactosidase expression to exogenous promoters) into developmentally regulated genes were used to investigate extracellular complementation of the A group mutations. A- mutations reduced developmental beta-galactosidase expression from 18 of 21 Tn5 lac insertions tested and that expression was restored to A- Tn5 lac cells by adding wild-type cells. The earliest A-dependent Tn5 lac normally expresses beta-galactosidase at 1.5 hr of development indicating a developmental block at 1-2 hr in A- mutants. A substance which can rescue the expression of this early Tn5 lac is released by wild-type (A+) but not by A- cells. This substance appears in a cell-free wash of wild-type cells or in starvation buffer conditioned by wild-type cells 1-2 hr after development is initiated. The conditioned starvation buffer also restores normal morphological development to an A- mutant.
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D002450:Cell Communication; D003001:Cloning, Molecular; D004251:DNA Transposable Elements; D005786:Gene Expression Regulation; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D009154:Mutation; D009231:Myxococcales / Q000166:cytology / Q000235:genetics*; D013171:Spores, Bacterial; D001616:beta-Galactosidase / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D001616:beta-Galactosidase