An essential nonredundant role for mycobacterial DnaK in native protein folding.
Protein chaperones are essential in all domains of life to prevent and resolve protein misfolding during translation and proteotoxic stress. HSP70 family chaperones, including E. coli DnaK, function in stress induced protein refolding and degradation, but are dispensable for cellular viability due t...
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2014-07-01
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| Series: | PLoS Genetics |
| Online Access: | http://europepmc.org/articles/PMC4109909?pdf=render |
| _version_ | 1819070509928677376 |
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| author | Allison Fay Michael S Glickman |
| author_facet | Allison Fay Michael S Glickman |
| author_sort | Allison Fay |
| collection | DOAJ |
| description | Protein chaperones are essential in all domains of life to prevent and resolve protein misfolding during translation and proteotoxic stress. HSP70 family chaperones, including E. coli DnaK, function in stress induced protein refolding and degradation, but are dispensable for cellular viability due to redundant chaperone systems that prevent global nascent peptide insolubility. However, the function of HSP70 chaperones in mycobacteria, a genus that includes multiple human pathogens, has not been examined. We find that mycobacterial DnaK is essential for cell growth and required for native protein folding in Mycobacterium smegmatis. Loss of DnaK is accompanied by proteotoxic collapse characterized by the accumulation of insoluble newly synthesized proteins. DnaK is required for solubility of large multimodular lipid synthases, including the essential lipid synthase FASI, and DnaK loss is accompanied by disruption of membrane structure and increased cell permeability. Trigger Factor is nonessential and has a minor role in native protein folding that is only evident in the absence of DnaK. In unstressed cells, DnaK localizes to multiple, dynamic foci, but relocalizes to focal protein aggregates during stationary phase or upon expression of aggregating peptides. Mycobacterial cells restart cell growth after proteotoxic stress by isolating persistent DnaK containing protein aggregates away from daughter cells. These results reveal unanticipated essential nonredunant roles for mycobacterial DnaK in mycobacteria and indicate that DnaK defines a unique susceptibility point in the mycobacterial proteostasis network. |
| first_indexed | 2024-12-21T17:07:05Z |
| format | Article |
| id | doaj.art-faba580063e74fc7a5070c5571a27a03 |
| institution | Directory Open Access Journal |
| issn | 1553-7390 1553-7404 |
| language | English |
| last_indexed | 2024-12-21T17:07:05Z |
| publishDate | 2014-07-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Genetics |
| spelling | doaj.art-faba580063e74fc7a5070c5571a27a032022-12-21T18:56:30ZengPublic Library of Science (PLoS)PLoS Genetics1553-73901553-74042014-07-01107e100451610.1371/journal.pgen.1004516An essential nonredundant role for mycobacterial DnaK in native protein folding.Allison FayMichael S GlickmanProtein chaperones are essential in all domains of life to prevent and resolve protein misfolding during translation and proteotoxic stress. HSP70 family chaperones, including E. coli DnaK, function in stress induced protein refolding and degradation, but are dispensable for cellular viability due to redundant chaperone systems that prevent global nascent peptide insolubility. However, the function of HSP70 chaperones in mycobacteria, a genus that includes multiple human pathogens, has not been examined. We find that mycobacterial DnaK is essential for cell growth and required for native protein folding in Mycobacterium smegmatis. Loss of DnaK is accompanied by proteotoxic collapse characterized by the accumulation of insoluble newly synthesized proteins. DnaK is required for solubility of large multimodular lipid synthases, including the essential lipid synthase FASI, and DnaK loss is accompanied by disruption of membrane structure and increased cell permeability. Trigger Factor is nonessential and has a minor role in native protein folding that is only evident in the absence of DnaK. In unstressed cells, DnaK localizes to multiple, dynamic foci, but relocalizes to focal protein aggregates during stationary phase or upon expression of aggregating peptides. Mycobacterial cells restart cell growth after proteotoxic stress by isolating persistent DnaK containing protein aggregates away from daughter cells. These results reveal unanticipated essential nonredunant roles for mycobacterial DnaK in mycobacteria and indicate that DnaK defines a unique susceptibility point in the mycobacterial proteostasis network.http://europepmc.org/articles/PMC4109909?pdf=render |
| spellingShingle | Allison Fay Michael S Glickman An essential nonredundant role for mycobacterial DnaK in native protein folding. PLoS Genetics |
| title | An essential nonredundant role for mycobacterial DnaK in native protein folding. |
| title_full | An essential nonredundant role for mycobacterial DnaK in native protein folding. |
| title_fullStr | An essential nonredundant role for mycobacterial DnaK in native protein folding. |
| title_full_unstemmed | An essential nonredundant role for mycobacterial DnaK in native protein folding. |
| title_short | An essential nonredundant role for mycobacterial DnaK in native protein folding. |
| title_sort | essential nonredundant role for mycobacterial dnak in native protein folding |
| url | http://europepmc.org/articles/PMC4109909?pdf=render |
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