解旋酶介导的SSU过程成熟和拆卸机制，这一成果由洛克菲勒大学Sebastian Klinge研究组经过不懈努力而取得。该项研究成果发表在2025年10月29日出版的《自然》上。

在这里，该团队报告了16个天然SSU加工体结构以及遗传数据，揭示了两种解旋酶，Mtr4 -外泌体和Dhr1，是如何控制精确和单向核糖体生物发生的。他们的数据显示，冗余拴住的RNA外泌体如何不可逆地降解核糖体前RNA，将SSU过程体转化为40s前颗粒，在此过程中，Utp14可以探测进化的表面，最终定位并激活Dhr1来解开U3 snoRNA并启动核核40s前释放。这项研究强调了一个大型动态RNA -蛋白复合物的范例，其中不可逆的RNA降解驱动组成变化，并将这些变化传达给酶活性，同时保持整体质量控制。

据了解，真核核糖体小亚基（SSU）的组装需要SSU过程体，这是一种含有RNA伴侣U3小核仁RNA （snoRNA）的核仁前体。由于缺乏中间体，SSU过程成熟、重塑、拆卸和RNA质量控制以及状态之间转换的潜在分子机制仍然未知。

附：英文原文

Title: Helicase-mediated mechanism of SSU processome maturation and disassembly

Author: Buzovetsky, Olga, Klinge, Sebastian

Issue&Volume: 2025-10-29

Abstract: Eukaryotic ribosomal small subunit (SSU) assembly requires the SSU processome, a nucleolar precursor containing the RNA chaperone U3 small nucleolar RNA (snoRNA). The underlying molecular mechanisms of SSU processome maturation, remodelling, disassembly and RNA quality control, and the transitions between states remain unknown owing to a paucity of intermediates1,2,3. Here we report 16 native SSU processome structures alongside genetic data, revealing how two helicases, the Mtr4-exosome and Dhr1, are controlled for accurate and unidirectional ribosome biogenesis. Our data show how irreversible pre-ribosomal RNA degradation by the redundantly tethered RNA exosome couples the transformation of the SSU processome into a pre-40S particle, during which Utp14 can probe evolving surfaces, ultimately positioning and activating Dhr1 to unwind the U3 snoRNA and initiate nucleolar pre-40S release. This study highlights a paradigm for large dynamic RNA–protein complexes in which irreversible RNA degradation drives compositional changes and communicates these changes to govern enzyme activity while maintaining overall quality control.

DOI: 10.1038/s41586-025-09688-3

Source: https://www.nature.com/articles/s41586-025-09688-3