Japan Agency for Medical Research and Development (AMED)
JP21am0101071
日本
Japan Agency for Medical Research and Development (AMED)
JP21am0101091
日本
引用
ジャーナル: Nat Commun / 年: 2025 タイトル: Structural basis of transfer RNA processing by bacterial minimal RNase P. 著者: Takamasa Teramoto / Takeshi Koyasu / Takashi Yokogawa / Naruhiko Adachi / Kouta Mayanagi / Takahiro Nakamura / Toshiya Senda / Yoshimitsu Kakuta / 要旨: Precursor tRNAs (pre-tRNAs) require nucleolytic removal of 5'-leader and 3'-trailer sequences for maturation, which is essential for proper tRNA function. The endoribonuclease RNase P exists in ...Precursor tRNAs (pre-tRNAs) require nucleolytic removal of 5'-leader and 3'-trailer sequences for maturation, which is essential for proper tRNA function. The endoribonuclease RNase P exists in diverse forms, including RNA- and protein-based RNase P, and removes 5'-leader sequences from pre-tRNAs. Some bacteria and archaea possess a unique minimal protein-based RNase P enzyme, HARP, which forms dodecamers with twelve active sites. Here, we present cryogenic electron microscopy structures of HARP dodecamers complexed with five pre-tRNAs, and we show that HARP oligomerization enables specific recognition of the invariant distance between the acceptor stem 5'-end and the TψC-loop, functioning as a molecular ruler-a feature representing convergent evolution among RNase P enzymes. The HARP dodecamer uses only five active sites for 5'-leader cleavage, while we identify a 3'-trailer cleavage activity in the remaining seven sites. This elucidation reveals how small proteins evolve through oligomerization to adapt a pivotal biological function (5'-leader processing) and acquire a novel function (3'-trailer processing).
モデルのタイプ: OTHER 詳細: An ab initio model was generated using RELION3's own implementation of Stochastic Gradient Descent (SGD) algorithm and low-pass filtered to 60 A for use as an initial model for 3D classification.