Université Paris-Saclay, UVSQ, Inserm, Infection et inflammation, Montigny-Le-Bretonneux, France.
Université Paris-Saclay, Université d'Evry, Laboratoire Européen de Recherche pour la Polyarthrite rhumatoïde-Genhotel, Evry, France.
Microbiol Spectr. 2024 Mar 5;12(3):e0352823. doi: 10.1128/spectrum.03528-23. Epub 2024 Feb 14.
is a non-tuberculous mycobacterium, causing lung infections in cystic fibrosis patients. During pulmonary infection, switches from smooth (Mabs-S) to rough (Mabs-R) morphotypes, the latter being hyper-virulent. Previously, we isolated the gene as differentially expressed during S-to-R transition. encodes a pleiotropic transcription factor that falls under the superfamily of nucleoid-associated proteins. Here, we used two functional genomic methods, RNA-seq and chromatin immunoprecipitation-sequencing (ChIP-seq), to elucidate the molecular role of Lsr2 in the pathobiology of . Transcriptomic analysis shows that Lsr2 differentially regulates gene expression across both morphotypes, most of which are involved in several key cellular processes of , including host adaptation and antibiotic resistance. These results were confirmed through quantitative real-time PCR, as well as by minimum inhibitory concentration tests and infection tests on macrophages in the presence of antibiotics. ChIP-seq analysis revealed that Lsr2 extensively binds the genome at AT-rich sequences and appears to form long domains that participate in the repression of its target genes. Unexpectedly, the genomic distribution of Lsr2 revealed no distinctions between Mabs-S and Mabs-R, implying more intricate mechanisms at play for achieving target selectivity.IMPORTANCELsr2 is a crucial transcription factor and chromosome organizer involved in intracellular growth and virulence in the smooth and rough morphotypes of . Using RNA-seq and chromatin immunoprecipitation-sequencing (ChIP-seq), we investigated the molecular role of Lsr2 in gene expression regulation along with its distribution on genome. Our study demonstrates the pleiotropic regulatory role of Lsr2, regulating the expression of many genes coordinating essential cellular and molecular processes in both morphotypes. In addition, we have elucidated the role of Lsr2 in antibiotic resistance both and , where mutant strains display heightened sensitivity to antibiotics. Through ChIP-seq, we reported the widespread distribution of Lsr2 on genome, revealing a direct repressive effect due to its extensive binding on promoters or coding sequences of its targets. This study unveils the significant regulatory role of Lsr2, intricately intertwined with its function in shaping the organization of the genome.
是一种非结核分枝杆菌，可引起囊性纤维化患者肺部感染。在肺部感染过程中，从光滑（Mabs-S）形态转变为粗糙（Mabs-R）形态，后者具有更强的毒力。此前，我们已分离出在 S 到 R 转变过程中差异表达的 基因。编码一种多效转录因子，属于核相关蛋白超家族。在这里，我们使用两种功能基因组方法，RNA-seq 和染色质免疫沉淀测序（ChIP-seq），阐明了 Lsr2 在 病理学中的分子作用。转录组分析表明，Lsr2 在两种形态中都能差异调节基因表达，其中大多数基因涉及 的几个关键细胞过程，包括宿主适应和抗生素耐药性。这些结果通过定量实时 PCR 以及在存在抗生素的情况下对巨噬细胞进行最小抑菌浓度试验和感染试验得到了证实。ChIP-seq 分析显示，Lsr2 广泛结合在富含 AT 的 基因组序列上，并且似乎形成了参与其靶基因抑制的长结构域。出乎意料的是，Lsr2 的基因组分布在 Mabs-S 和 Mabs-R 之间没有区别，这表明在实现靶基因选择性方面存在更复杂的机制。重要的是，Lsr2 是一种关键的转录因子和染色体组织者，参与光滑和粗糙形态的 细胞内生长和毒力。使用 RNA-seq 和染色质免疫沉淀测序（ChIP-seq），我们研究了 Lsr2 在基因表达调控以及其在 基因组上的分布中的分子作用。我们的研究表明，Lsr2 具有多效调节作用，调节两种形态中许多协调重要细胞和分子过程的基因表达。此外，我们还阐明了 Lsr2 在抗生素耐药性中的作用， 突变株对抗生素的敏感性增加。通过 ChIP-seq，我们报告了 Lsr2 在 基因组上的广泛分布，揭示了由于其广泛结合在靶基因的启动子或编码序列上而产生的直接抑制作用。这项研究揭示了 Lsr2 的重要调节作用，它与它在塑造 基因组组织中的功能紧密交织在一起。
