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The Min oscillator uses MinD-dependent conformational changes in MinE to spatially regulate cytokinesis.

ABSTRACT: In E. coli, MinD recruits MinE to the membrane, leading to a coupled oscillation required for spatial regulation of the cytokinetic Z ring. How these proteins interact, however, is not clear because the MinD-binding regions of MinE are sequestered within a six-stranded ? sheet and masked by N-terminal helices. minE mutations that restore interaction between some MinD and MinE mutants were isolated. These mutations alter the MinE structure leading to release of the MinD-binding regions and the N-terminal helices that bind the membrane. Crystallization of MinD-MinE complexes revealed a four-stranded ? sheet MinE dimer with the released ? strands (MinD-binding regions) converted to ? helices bound to MinD dimers. These results identify the MinD-dependent conformational changes in MinE that convert it from a latent to an active form and lead to a model of how MinE persists at the MinD-membrane surface.

SUBMITTER: Park KT

PROVIDER: S-EPMC3155264 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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The Min oscillator uses MinD-dependent conformational changes in MinE to spatially regulate cytokinesis.

Park Kyung-Tae KT Wu Wei W Battaile Kevin P KP Lovell Scott S Holyoak Todd T Lutkenhaus Joe J

Cell 20110801 3

In E. coli, MinD recruits MinE to the membrane, leading to a coupled oscillation required for spatial regulation of the cytokinetic Z ring. How these proteins interact, however, is not clear because the MinD-binding regions of MinE are sequestered within a six-stranded β sheet and masked by N-terminal helices. minE mutations that restore interaction between some MinD and MinE mutants were isolated. These mutations alter the MinE structure leading to release of the MinD-binding regions and the N- ...[more]

PMID: 21816275

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MinE conformational dynamics regulate membrane binding, MinD interaction, and Min oscillation.

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Mechanistic insights of the Min oscillator via cell-free reconstitution and imaging.

Project description:The MinD and MinE proteins of Escherichia coli self-organize into a standing-wave oscillator on the membrane to help align division at mid-cell. When unleashed from cellular confines, MinD and MinE form a spectrum of patterns on artificial bilayers-static amoebas, traveling waves, traveling mushrooms, and bursts with standing-wave dynamics. We recently focused our cell-free studies on bursts because their dynamics recapitulate many features of Min oscillation observed in vivo. The data unveiled a patterning mechanism largely governed by MinE regulation of MinD interaction with membrane. We proposed that the MinD to MinE ratio on the membrane acts as a toggle switch between MinE-stimulated recruitment and release of MinD from the membrane. In this review, we summarize cell-free data on the Min system and expand upon a molecular mechanism that provides a biochemical explanation as to how these two 'simple' proteins can form the remarkable spectrum of patterns.

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