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Structural insights into stressosome assembly
The stressosome transduces environmental stress signals to SigB to upregulate SigB-dependent transcription, which is required for bacterial viability. The stressosome core is composed of RsbS and at least one of the RsbR paralogs. A previous cryo-electron microscopy (cryo-EM) structure of the RsbRA–...
Autores principales: | , , , , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
International Union of Crystallography
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6760441/ https://www.ncbi.nlm.nih.gov/pubmed/31576226 http://dx.doi.org/10.1107/S205225251900945X |
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author | Kwon, Eunju Pathak, Deepak Kim, Han-ul Dahal, Pawan Ha, Sung Chul Lee, Seung Sik Jeong, Hyeongseop Jeoung, Dooil Chang, Hyeun Wook Jung, Hyun Suk Kim, Dong Young |
author_facet | Kwon, Eunju Pathak, Deepak Kim, Han-ul Dahal, Pawan Ha, Sung Chul Lee, Seung Sik Jeong, Hyeongseop Jeoung, Dooil Chang, Hyeun Wook Jung, Hyun Suk Kim, Dong Young |
author_sort | Kwon, Eunju |
collection | PubMed |
description | The stressosome transduces environmental stress signals to SigB to upregulate SigB-dependent transcription, which is required for bacterial viability. The stressosome core is composed of RsbS and at least one of the RsbR paralogs. A previous cryo-electron microscopy (cryo-EM) structure of the RsbRA–RsbS complex determined under a D2 symmetry restraint showed that the stressosome core forms a pseudo-icosahedron consisting of 60 STAS domains of RsbRA and RsbS. However, it is still unclear how RsbS and one of the RsbR paralogs assemble into the stressosome. Here, an assembly model of the stressosome is presented based on the crystal structure of the RsbS icosahedron and cryo-EM structures of the RsbRA–RsbS complex determined under diverse symmetry restraints (nonsymmetric C1, dihedral D2 and icosahedral I envelopes). 60 monomers of the crystal structure of RsbS fitted well into the I-restrained cryo-EM structure determined at 4.1 Å resolution, even though the STAS domains in the I envelope were averaged. This indicates that RsbS and RsbRA share a highly conserved STAS fold. 22 protrusions observed in the C1 envelope, corresponding to dimers of the RsbRA N-domain, allowed the STAS domains of RsbRA and RsbS to be distinguished in the stressosome core. Based on these, the model of the stressosome core was reconstructed. The mutation of RsbRA residues at the binding interface in the model (R189A/Q191A) significantly reduced the interaction between RsbRA and RsbS. These results suggest that nonconserved residues in the conserved STAS folds between RsbS and RsbR paralogs determine stressosome assembly. |
format | Online Article Text |
id | pubmed-6760441 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | International Union of Crystallography |
record_format | MEDLINE/PubMed |
spelling | pubmed-67604412019-10-01 Structural insights into stressosome assembly Kwon, Eunju Pathak, Deepak Kim, Han-ul Dahal, Pawan Ha, Sung Chul Lee, Seung Sik Jeong, Hyeongseop Jeoung, Dooil Chang, Hyeun Wook Jung, Hyun Suk Kim, Dong Young IUCrJ Research Papers The stressosome transduces environmental stress signals to SigB to upregulate SigB-dependent transcription, which is required for bacterial viability. The stressosome core is composed of RsbS and at least one of the RsbR paralogs. A previous cryo-electron microscopy (cryo-EM) structure of the RsbRA–RsbS complex determined under a D2 symmetry restraint showed that the stressosome core forms a pseudo-icosahedron consisting of 60 STAS domains of RsbRA and RsbS. However, it is still unclear how RsbS and one of the RsbR paralogs assemble into the stressosome. Here, an assembly model of the stressosome is presented based on the crystal structure of the RsbS icosahedron and cryo-EM structures of the RsbRA–RsbS complex determined under diverse symmetry restraints (nonsymmetric C1, dihedral D2 and icosahedral I envelopes). 60 monomers of the crystal structure of RsbS fitted well into the I-restrained cryo-EM structure determined at 4.1 Å resolution, even though the STAS domains in the I envelope were averaged. This indicates that RsbS and RsbRA share a highly conserved STAS fold. 22 protrusions observed in the C1 envelope, corresponding to dimers of the RsbRA N-domain, allowed the STAS domains of RsbRA and RsbS to be distinguished in the stressosome core. Based on these, the model of the stressosome core was reconstructed. The mutation of RsbRA residues at the binding interface in the model (R189A/Q191A) significantly reduced the interaction between RsbRA and RsbS. These results suggest that nonconserved residues in the conserved STAS folds between RsbS and RsbR paralogs determine stressosome assembly. International Union of Crystallography 2019-08-21 /pmc/articles/PMC6760441/ /pubmed/31576226 http://dx.doi.org/10.1107/S205225251900945X Text en © Eunju Kwon et al. 2019 http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.http://creativecommons.org/licenses/by/4.0/ |
spellingShingle | Research Papers Kwon, Eunju Pathak, Deepak Kim, Han-ul Dahal, Pawan Ha, Sung Chul Lee, Seung Sik Jeong, Hyeongseop Jeoung, Dooil Chang, Hyeun Wook Jung, Hyun Suk Kim, Dong Young Structural insights into stressosome assembly |
title | Structural insights into stressosome assembly |
title_full | Structural insights into stressosome assembly |
title_fullStr | Structural insights into stressosome assembly |
title_full_unstemmed | Structural insights into stressosome assembly |
title_short | Structural insights into stressosome assembly |
title_sort | structural insights into stressosome assembly |
topic | Research Papers |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6760441/ https://www.ncbi.nlm.nih.gov/pubmed/31576226 http://dx.doi.org/10.1107/S205225251900945X |
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