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Interplay between transcriptional regulators and VapBC toxin-antitoxin loci during thermal stress response in extremely thermoacidophilic archaea.

ABSTRACT: Thermoacidophilic archaea lack sigma factors and the large inventory of heat shock proteins (HSPs) widespread in bacterial genomes, suggesting other strategies for handling thermal stress are involved. Heat shock transcriptomes for the thermoacidophilic archaeon Saccharolobus (f. Sulfolobus) solfataricus 98/2 revealed genes that were highly responsive to thermal stress, including transcriptional regulators YtrA_Ss (Ssol_2420) and FadR_Ss (Ssol_0314), as well as type II toxin-antitoxin (TA) loci VapBC6 (Ssol_2337, Ssol_2338) and VapBC22 (Ssol_0819, Ssol_0818). The role, if any, of type II TA loci during stress response in microorganisms, such as Escherichia coli, is controversial. But, when genes encoding YtrA_Ss , FadR_Ss , VapC22, VapB6, and VapC6 were systematically mutated in Sa. solfataricus 98/2, significant up-regulation of the other genes within this set was observed, implicating an interconnected regulatory network during thermal stress response. VapBC6 and VapBC22 have close homologues in other Sulfolobales, as well as in other archaea (e.g. Pyrococcus furiosus and Archaeoglobus fulgidus), and their corresponding genes were also heat shock responsive. The interplay between VapBC TA loci and heat shock regulators in Sa solfataricus 98/2 not only indicates a cellular mechanism for heat shock response that differs from bacteria but one that could have common features within the thermophilic archaea.

SUBMITTER: Cooper CR

PROVIDER: S-EPMC10580297 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Interplay between transcriptional regulators and VapBC toxin-antitoxin loci during thermal stress response in extremely thermoacidophilic archaea.

Cooper Charlotte R CR Lewis April M AM Notey Jaspreet S JS Mukherjee Arpan A Willard Daniel J DJ Blum Paul H PH Kelly Robert M RM

Environmental microbiology 20230224 6

Thermoacidophilic archaea lack sigma factors and the large inventory of heat shock proteins (HSPs) widespread in bacterial genomes, suggesting other strategies for handling thermal stress are involved. Heat shock transcriptomes for the thermoacidophilic archaeon Saccharolobus (f. Sulfolobus) solfataricus 98/2 revealed genes that were highly responsive to thermal stress, including transcriptional regulators YtrA<sub>Ss</sub> (Ssol_2420) and FadR<sub>Ss</sub> (Ssol_0314), as well as type II toxin- ...[more]

PMID: 36752722

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Dataset Information

Interplay between transcriptional regulators and VapBC toxin-antitoxin loci during thermal stress response in extremely thermoacidophilic archaea.

Publications

Interplay between transcriptional regulators and VapBC toxin-antitoxin loci during thermal stress response in extremely thermoacidophilic archaea.

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