Scholarlink

<p>In the bacterial Csr/Rsm system, non-coding RNAs activate mRNA translation by removing homodimeric Csr/Rsm proteins from ribosome-binding sites of mRNAs. In <i>Pseudomonas protegens</i>, each RsmZ ncRNA sequesters up to five RsmE dimers sequentially and specifically within a narrow affinity range, functioning as a ‘protein sponge’. Although the RsmE binding cascade is cooperative, binding of the highest affinity stem-loop RNA in RsmZ (SL2) reduces RNA binding affinity at the second site 10- to 30-fold. This unusual negative cooperativity may facilitate RsmE release from tightly bound mRNA for handover to the non-coding RNA, yet the underlying mechanisms remain unclear. Using Isothermal Titration Calorimetry, NMR spectroscopy and Molecular Dynamics, we reveal an allosteric mechanism resembling a Newton’s cradle, coupling the binding at one site to conformational and dynamic changes at the second site, explaining the reduced affinity of the second binding event, and handover of RsmE dimer from mRNA to the ncRNA RsmZ.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Newton’s cradle-like allosteric mechanism explains regulatory RsmE RNA binding

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年4月22日

查看全文
  • Esteban Finol,
  • Fred F. Damberger,
  • Miroslav Krepl,
  • Timo Flügel,
  • Priscilla Dietrich,
  • Thomas C. T. Michaels,
  • Beat Vögeli,
  • Jiří Šponer,
  • Frédéric H-T. Allain

摘要

In the bacterial Csr/Rsm system, non-coding RNAs activate mRNA translation by removing homodimeric Csr/Rsm proteins from ribosome-binding sites of mRNAs. In Pseudomonas protegens, each RsmZ ncRNA sequesters up to five RsmE dimers sequentially and specifically within a narrow affinity range, functioning as a ‘protein sponge’. Although the RsmE binding cascade is cooperative, binding of the highest affinity stem-loop RNA in RsmZ (SL2) reduces RNA binding affinity at the second site 10- to 30-fold. This unusual negative cooperativity may facilitate RsmE release from tightly bound mRNA for handover to the non-coding RNA, yet the underlying mechanisms remain unclear. Using Isothermal Titration Calorimetry, NMR spectroscopy and Molecular Dynamics, we reveal an allosteric mechanism resembling a Newton’s cradle, coupling the binding at one site to conformational and dynamic changes at the second site, explaining the reduced affinity of the second binding event, and handover of RsmE dimer from mRNA to the ncRNA RsmZ.