A Myxococcus xanthus cell density-sensing system required for multicellular development.

H B Kaplan; L Plamann

doi:10.1111/j.1574-6968.1996.tb08185.x

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A Myxococcus xanthus cell density-sensing system required for multicellular development.

H B Kaplan·L Plamann

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Abstract

Progression through early Myxococcus xanthus multicellular fruiting body development requires the generation of and response to extracellular A signal. Extracellular A signal is a specific set of amino acids at an extracellular concentration greater than 10 muM. It functions as a cell density signal during starvation that allows the cells to sense that a minimal cell density has been reached and development can proceed. The generation of extracellular A signal requires the products of three asg genes. They have recently been identified as AsgA, a fused two-component histidine protein kinase and response regulator; AsgB, a putative DNA-binding protein; and AsgC, the M, xanthus major sigma factor. Other elements of the A signaling pathway map to the sasB locus and appear to be A signal transducers. These elements are regulators of the earliest A signal-dependent gene, whose promoter is a member of the sigma-54 family. Continued study of the A signaling pathway is expected to identify additional components of this network required for the complex behavioural response of fruiting body formation.

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Cell Count Myxococcus xanthus Signal Transduction Journal Article Research Support, U.S. Gov't, P.H.S.Review

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H B Kaplan, L Plamann. 1996-06-01. A Myxococcus xanthus cell density-sensing system required for multicellular development.. https://doi.org/10.1111/j.1574-6968.1996.tb08185.x

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