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SpxA1 and SpxA2 Function as a Stoichiometry-Dependent Regulatory Rheostat Governing Virulence Gene Expression in Group A Streptococcus — CovR ChIP-exo dataset

ABSTRACT: Group A Streptococcus (GAS) encodes two paralogs of the Spx transcriptional regulator, SpxA1 and SpxA2, which interact with RNA polymerase to modulate virulence gene expression. SpxA2 is directly regulated by the LiaFSR three-component system in response to antimicrobial peptide stress. To define how SpxA2 influences CovR DNA occupancy genome-wide, we performed chromatin immunoprecipitation with exonuclease treatment (ChIP-exo) targeting CovR in wild-type MGAS10870 (emm3), an isogenic spxA2 deletion mutant (deltaSpxA2), and a LiaSQ146A constitutively active LiaS mutant used as a SpxA2 overexpression surrogate (SpxA2-OE). Differential binding analysis identified 439 sites with significantly altered CovR occupancy between wild-type and deltaSpxA2 (FDR < 0.05), with class-specific enrichment of CovR dimer and monomer binding motifs consistent with the two-class CovR binding model (Horstmann et al. 2023). These data contribute to a multi-omic analysis including RNA-seq, DIA proteomics, and NanoString nCounter that defines the regulatory roles of SpxA1 and SpxA2 in GAS pathogenesis.

ORGANISM(S): Streptococcus pyogenes

PROVIDER: GSE334313 | GEO | 2026/07/13

REPOSITORIES: GEO

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SpxA1 and SpxA2 Function as a Stoichiometry-Dependent Regulatory Rheostat Governing Virulence Gene Expression in Group A Streptococcus — RNA-seq dataset

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2026-07-13 | GSE334312 | GEO

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