CtpB assembles a gated protease tunnel regulating cell-cell signaling during spore formation in Bacillus subtilis.
| Autor: | Mastny M; Research Institute of Molecular Pathology, 1030 Vienna, Austria., Heuck A, Kurzbauer R, Heiduk A, Boisguerin P, Volkmer R, Ehrmann M, Rodrigues CD, Rudner DZ, Clausen T |
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| Jazyk: | angličtina |
| Zdroj: | Cell [Cell] 2013 Oct 24; Vol. 155 (3), pp. 647-58. Date of Electronic Publication: 2013 Oct 24. |
| DOI: | 10.1016/j.cell.2013.09.050 |
| Abstrakt: | Spore formation in Bacillus subtilis relies on a regulated intramembrane proteolysis (RIP) pathway that synchronizes mother-cell and forespore development. To address the molecular basis of this SpoIV transmembrane signaling, we carried out a structure-function analysis of the activating protease CtpB. Crystal structures reflecting distinct functional states show that CtpB constitutes a ring-like protein scaffold penetrated by two narrow tunnels. Access to the proteolytic sites sequestered within these tunnels is controlled by PDZ domains that rearrange upon substrate binding. Accordingly, CtpB resembles a minimal version of a self-compartmentalizing protease regulated by a unique allosteric mechanism. Moreover, biochemical analysis of the PDZ-gated channel combined with sporulation assays reveal that activation of the SpoIV RIP pathway is induced by the concerted activity of CtpB and a second signaling protease, SpoIVB. This proteolytic mechanism is of broad relevance for cell-cell communication, illustrating how distinct signaling pathways can be integrated into a single RIP module. (Copyright © 2013 Elsevier Inc. All rights reserved.) |
| Databáze: | MEDLINE |
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