title: Two-Component Signal Transduction Systems That Regulate the Temporal and Spatial Expression of Myxococcus xanthus Sporulation Genes.
abstract: When starved for nutrients, Myxococcus xanthus produces a biofilm that contains a mat of rod-shaped cells, known as peripheral rods, and aerial structures called fruiting bodies, which house thousands of dormant and stress-resistant spherical spores. Because rod-shaped cells differentiate into spherical, stress-resistant spores and spore differentiation occurs only in nascent fruiting bodies, many genes and multiple levels of regulation are required. Over the past 2 decades, many regulators of the temporal and spatial expression of M. xanthus sporulation genes have been uncovered. Of these sporulation gene regulators, two-component signal transduction circuits, which typically contain a histidine kinase sensor protein and a transcriptional regulator known as response regulator, are among the best characterized. In this review, we discuss prototypical two-component systems (Nla6S/Nla6 and Nla28S/Nla28) that regulate an early, preaggregation phase of sporulation gene expression during fruiting body development. We also discuss orphan response regulators (ActB and FruA) that regulate a later phase of sporulation gene expression, which begins during the aggregation stage of fruiting body development. In addition, we summarize the research on a complex two-component system (Esp) that is important for the spatial regulation of sporulation.
authors.affiliation: Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, New York, USA.
authors.forename: Zaara
authors.initials: Z
authors.lastname: Sarwar
authors.affiliation: Department of Biology, Syracuse University, Syracuse, New York, USA agarza@syr.edu.
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Garza
mesh_terms: D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D016941:Myxococcus xanthus / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D013171:Spores, Bacterial / Q000235:genetics / Q000502:physiology*; D013997:Time Factors