Caballero Sánchez, Carlos

Profile Picture

Email Address

person.page.identifierURI

https://academica-e.unavarra.es/handle/2454/48766

Birth Date

Job Title

Last Name

Caballero Sánchez

First Name

Carlos

person.page.departamento

Producción Agraria

person.page.instituteName

ORCID

person.page.observainves

752018

person.page.upna

810919

Name

Filters

2018 - 201922020 - 20221
Reset filters

Settings

Author: Caballero Sánchez, Carlos × Subject: Staphylococcus aureus ×

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    PublicationOpen Access
    The regulon of the RNA chaperone CspA and its auto-regulation in Staphylococcus aureus
    (Oxford University Press, 2018) Caballero Sánchez, Carlos; Menéndez Gil, Pilar; Catalán Moreno, Arancha; Vergara Irigaray, Marta; García Martínez, Begoña; Segura, Víctor; Irurzun Domínguez, Naiara; Villanueva San Martín, Maite; Ruiz de los Mozos Aliaga, Igor; Solano Goñi, Cristina; Lasa Uzcudun, Íñigo; Toledo Arana, Alejandro; IdAB. Instituto de Agrobiotecnología / Agrobioteknologiako Institutua; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
    RNA-binding proteins (RBPs) are essential to finetune gene expression. RBPs containing the coldshock domain are RNA chaperones that have been extensively studied. However, the RNA targets and specific functions for many of them remain elusive. Here, combining comparative proteomics and RBPimmunoprecipitation- microarray profiling, we have determined the regulon of the RNA chaperone CspA of Staphylococcus aureus. Functional analysis revealed that proteins involved in carbohydrate and ribonucleotide metabolism, stress response and virulence gene expression were affected by cspA deletion. Stress-associated phenotypes such as increased bacterial aggregation and diminished resistance to oxidative-stress stood out. Integration of the proteome and targetome showed that CspA posttranscriptionally modulates both positively and negatively the expression of its targets, denoting additional functions to the previously proposed translation enhancement. One of these repressed targets was its own mRNA, indicating the presence of a negative post-transcriptional feedback loop. CspA bound the 5 UTR of its own mRNA disrupting a hairpin, which was previously described as an RNase III target. Thus, deletion of the cspA 5 UTR abrogated mRNA processing and auto-regulation. We propose that CspA interacts through a U-rich motif, which is located at the RNase III cleavage site, portraying CspA as a putative RNase III-antagonist.
  • Thumbnail Image
    PublicationOpen Access
    Regulation of heterogenous lexA expression in staphylococcus aureus by an antisense RNA originating from transcriptional read-through upon natural mispairings in the sbrB intrinsic terminator
    (MDPI, 2022) Bastet, Laurène; Bustos-Sanmamed, Pilar; Catalán Moreno, Arancha; Caballero Sánchez, Carlos; Cuesta Ferre, Sergio; Matilla Cuenca, Leticia; Villanueva San Martín, Maite; Valle Turrillas, Jaione; Lasa Uzcudun, Íñigo; Toledo Arana, Alejandro; IdAB. Instituto de Agrobiotecnología / Agrobioteknologiako Institutua
    Bacterial genomes are pervasively transcribed, generating a wide variety of antisense RNAs (asRNAs). Many of them originate from transcriptional read-through events (TREs) during the transcription termination process. Previous transcriptome analyses revealed that the lexA gene from Staphylococcus aureus, which encodes the main SOS response regulator, is affected by the presence of an asRNA. Here, we show that the lexA antisense RNA (lexA-asRNA) is generated by a TRE on the intrinsic terminator (TTsbrB) of the sbrB gene, which is located downstream of lexA, in the opposite strand. Transcriptional read-through occurs by a natural mutation that destabilizes the TTsbrB structure and modifies the efficiency of the intrinsic terminator. Restoring the mispairing mutation in the hairpin of TTsbrB prevented lexA-asRNA transcription. The level of lexA-asRNA directly correlated with cellular stress since the expressions of sbrB and lexA-asRNA depend on the stress transcription factor SigB. Comparative analyses revealed strain-specific nucleotide polymorphisms within TTsbrB, suggesting that this TT could be prone to accumulating natural mutations. A genome-wide analysis of TREs suggested that mispairings in TT hairpins might provide wider transcriptional connections with downstream genes and, ultimately, transcriptomic variability among S. aureus strains.
  • Thumbnail Image
    PublicationOpen Access
    Functional analysis of the RNA chaperone CspA in Staphylococcus aureus
    (2018) Caballero Sánchez, Carlos; Toledo Arana, Alejandro; Producción Agraria; Nekazaritza Ekoizpena
    En esta tesis se pone de manifiesto que las chaperonas de RNA, como CspA, pueden interactuar de manera específica con estructuras de RNA, que a su vez pueden ser reconocidas por otras RBPs. Esto contribuye a un mejor entendimiento de la regulación mediada por este grupo de chaperonas de RNA. Además, se destaca la importancia de los elementos reguladores intrínsecos, presentes en cada mRNA, y se propone que la interacción de dichos elementos con distintas RBPs es un factor clave para la correcta expresión proteica que, en última instancia, permite el adecuado desarrollo de todos los seres vivos.