| Full text | |
| Author(s): |
Santos, Juliana S.
[1]
;
da Silva, Carolina A. P. T.
[1]
;
Balhesteros, Heloise
[1]
;
Lourenco, Rogerio F.
[2]
;
Marques, Marilis V.
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Sao Paulo, Inst Ciencias Biomed, Dept Microbiol, BR-05508000 Sao Paulo, SP - Brazil
[2] Univ Sao Paulo, Inst Quim, Dept Bioquim, BR-05508000 Sao Paulo, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | BMC Genomics; v. 16, AUG 27 2015. |
| Web of Science Citations: | 4 |
| Abstract | |
Background: The Cold Shock proteins are RNA binding proteins involved in various cellular processes, including adaptation to low temperature, nutritional stress, cell growth and stationary phase. They may have an impact on gene expression by interfering with RNA stability and acting as transcription antiterminators. Caulobacter crescentus cspC is an essential gene encoding a stationary phase-induced protein of the Cold Shock Protein family and this work had as goal investigating the basis for the requirement of this gene for survival at this phase. In this work we investigate the role of CspC in C. crescentus stationary phase and discuss the molecular mechanisms that could be involved. Results: The expression of cspC increased significantly at stationary phase in complex media and in glucose depletion, indicating a putative role in responding to carbon starvation. Global transcriptional profiling experiments comparing cspC and the wild type strain both at exponential and stationary phases as well as comparing exponential and stationary phase in wild type strain were carried out by DNA microarray analysis. The results showed that the absence of cspC affected the transcription of 11 genes at exponential phase and 60 genes at stationary phase. Among the differentially expressed genes it is worth noting those encoding respiratory enzymes and genes for sulfur metabolism, which were upregulated, and those encoding enzymes of the glyoxylate cycle, which were severely downregulated in the mutant at stationary phase. mRNA decay experiments showed that the aceA mRNA, encoding isocitrate lyase, was less stable in the cspC mutant, indicating that this effect was at least partially due to posttranscriptional regulation. These observations were supported by the observed arrested growth phenotype of the cspC strain when grown in acetate as the sole carbon source, and by the upregulation of genes for assimilatory sulfate reduction and methionine biosynthesis. Conclusions: The stationary phase-induced RNA binding protein CspC has an important role in gene expression at this phase, and is necessary for maximal expression of the glyoxylate cycle genes. In the case of aceA, its downregulation may be attributed to the shorter half-life of the mRNA in the cspC mutant, indicating that one of the possible regulatory mechanisms is via altering RNA stabilization. (AU) | |
| FAPESP's process: | 14/04046-8 - Regulatory networks of bacterial stress response |
| Grantee: | Marilis Do Valle Marques |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 11/21883-2 - Characterization of the mechanisms of CspC action in Caulobacter crescentus cell viability and stress response |
| Grantee: | Juliana Santos Nakayama |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 12/10563-0 - Physiology and regulation of bacterial stress response |
| Grantee: | Marilis Do Valle Marques |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 11/17513-5 - Determination of genes regulated by the transcription factor SpdR and its involvement on stationary phase adaptation in Caulobacter crescentus |
| Grantee: | Carolina Antunes Do Prado Tavares da Silva |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |