title: A cascade of coregulating enhancer binding proteins initiates and propagates a multicellular developmental program.
abstract: The signal transduction networks that initiate multicellular development in bacteria remain largely undefined. Here, we report that Myxococcus xanthus regulates entry into its multicellular developmental program using a novel strategy: a cascade of transcriptional activators known as enhancer binding proteins (EBPs). The EBPs in the cascade function in sequential stages of early development, and several lines of evidence indicate that the cascade is propagated when EBPs that function at one stage of development directly regulate transcription of an EBP gene important for the next developmental stage. We also show that the regulatory cascade is designed in a novel way that extensively expands on the typical use of EBPs: Instead of using only one EBP to regulate a particular gene or group of genes, which is the norm in other bacterial systems, the cascade uses multiple EBPs to regulate EBP genes that are positioned at key transition points in early development. Based on the locations of the putative EBP promoter binding sites, several different mechanisms of EBP coregulation are possible, including the formation of coregulating EBP transcriptional complexes. We propose that M. xanthus uses an EBP coregulation strategy to make expression of EBP genes that modulate stage-stage transitions responsive to multiple signal transduction pathways, which provide information that is important for a coordinated decision to advance the developmental process.
authors.affiliation: Department of Biology, Syracuse University, Syracuse, NY 13244, USA.
authors.forename: Krista M
authors.initials: KM
authors.lastname: Giglio
authors.forename: Nora
authors.initials: N
authors.lastname: Caberoy
authors.forename: Garret
authors.initials: G
authors.lastname: Suen
authors.forename: Dale
authors.initials: D
authors.lastname: Kaiser
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Garza
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D024202:Electrophoretic Mobility Shift Assay; D004742:Enhancer Elements, Genetic / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D018507:Gene Expression Regulation, Developmental; D005798:Genes, Bacterial / Q000235:genetics; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D016941:Myxococcus xanthus / Q000166:cytology / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D009876:Operon / Q000235:genetics; D010641:Phenotype; D011401:Promoter Regions, Genetic; D011485:Protein Binding / Q000235:genetics; D051877:RNA Polymerase Sigma 54 / Q000235:genetics / Q000378:metabolism; D013171:Spores, Bacterial / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D051877:RNA Polymerase Sigma 54