The Lon Protease Links Nucleotide Metabolism with Proteotoxic Stress.
Mol Cell
; 79(5): 758-767.e6, 2020 09 03.
Article
em En
| MEDLINE
| ID: mdl-32755596
ABSTRACT
During proteotoxic stress, bacteria maintain critical processes like DNA replication while removing misfolded proteins, which are degraded by the Lon protease. Here, we show that in Caulobacter crescentus Lon controls deoxyribonucleoside triphosphate (dNTP) pools during stress through degradation of the transcription factor CcrM. Elevated dNTP/nucleotide triphosphate (NTP) ratios in Δlon cells protects them from deletion of otherwise essential deoxythymidine triphosphate (dTTP)-producing pathways and shields them from hydroxyurea-induced loss of dNTPs. Increased dNTP production in Δlon results from higher expression of ribonucleotide reductase driven by increased CcrM. We show that misfolded proteins can stabilize CcrM by competing for limited protease and that Lon-dependent control of dNTPs improves fitness during protein misfolding conditions. We propose that linking dNTP production with availability of Lon allows Caulobacter to maintain replication capacity when misfolded protein burden increases, such as during rapid growth. Because Lon recognizes misfolded proteins regardless of the stress, this mechanism allows for response to a variety of unanticipated conditions.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Caulobacter crescentus
/
Dobramento de Proteína
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Protease La
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Nucleotídeos
Idioma:
En
Revista:
Mol Cell
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Estados Unidos