TY - JOUR
T1 - Role of Salmonella Typhimurium small RNAs RyhB-1 and RyhB-2 in the oxidative stress response
AU - Calderón, Iván L.
AU - Morales, Eduardo H.
AU - Collao, Bernardo
AU - Calderón, Paulina F.
AU - Chahuán, Catalina A.
AU - Acuña, Lillian G.
AU - Gil, Fernando
AU - Saavedra, Claudia P.
N1 - Funding Information:
This work received financial support from FONDECYT 11110216 , FONDECYT 1120384 , UNAB DI-42-11/R and UNAB DI-340-13/R . We would also like to thank to Lionello Bossi and Nara Figueroa-Bossi for critical reading of the manuscript, helpful suggestions and for providing some bacterial strains.
PY - 2014/1
Y1 - 2014/1
N2 - As part of the response to specific stress conditions, bacteria express small molecules of non-coding RNA which maintain cellular homeostasis by regulating gene expression, commonly at the post-transcriptional level. Among these, in Salmonella enterica sv. Typhimurium, the paralog small non-coding RNAs RyhB-1 and RyhB-2 play an important role in iron homeostasis. In addition, in the present work, we show that RyhB-1 and RyhB-2 also participate in the response to hydrogen peroxide (H2O2). Deletion of RyhB-1 and/or RyhB-2 resulted in increased levels of intracellular reactive oxygen species, protein carbonylation and an altered NADH/NAD+ ratio. Analyses of the transcriptional profiles of ryhB-1 and ryhB-2 by northern blot and qRT-PCR showed that they are induced in response to H2O2 in an OxyR-dependent manner. By using lacZ-fusions and electrophoretic mobility shift assays, we confirmed the requirement of OxyR for inducing expression of both ryhB-1 and ryhB-2. Taken together, our results support a model in which, in response to peroxide treatment, ryhB-1 and ryhB-2 are upregulated by OxyR through direct interaction with their promoter region.
AB - As part of the response to specific stress conditions, bacteria express small molecules of non-coding RNA which maintain cellular homeostasis by regulating gene expression, commonly at the post-transcriptional level. Among these, in Salmonella enterica sv. Typhimurium, the paralog small non-coding RNAs RyhB-1 and RyhB-2 play an important role in iron homeostasis. In addition, in the present work, we show that RyhB-1 and RyhB-2 also participate in the response to hydrogen peroxide (H2O2). Deletion of RyhB-1 and/or RyhB-2 resulted in increased levels of intracellular reactive oxygen species, protein carbonylation and an altered NADH/NAD+ ratio. Analyses of the transcriptional profiles of ryhB-1 and ryhB-2 by northern blot and qRT-PCR showed that they are induced in response to H2O2 in an OxyR-dependent manner. By using lacZ-fusions and electrophoretic mobility shift assays, we confirmed the requirement of OxyR for inducing expression of both ryhB-1 and ryhB-2. Taken together, our results support a model in which, in response to peroxide treatment, ryhB-1 and ryhB-2 are upregulated by OxyR through direct interaction with their promoter region.
KW - Oxidative stress
KW - RyhB
KW - SRNA
UR - http://www.scopus.com/inward/record.url?scp=84893801940&partnerID=8YFLogxK
U2 - 10.1016/j.resmic.2013.10.008
DO - 10.1016/j.resmic.2013.10.008
M3 - Article
C2 - 24239962
AN - SCOPUS:84893801940
SN - 0923-2508
VL - 165
SP - 30
EP - 40
JO - Research in Microbiology
JF - Research in Microbiology
IS - 1
ER -