A network of assembly factors is involved in remodeling rRNA elements during preribosome maturation
A network of assembly factors is involved in remodeling rRNA elements during preribosome maturation
复制标题
DOI：
10.1083/jcb.201408111
复制
发表时间：
2014-11-24
影响因子：
7.8
通讯作者：
Hurt, Ed
中科院分区：
文献类型：
--
作者：
Bassler, Jochen;Paternoga, Helge;Hurt, Ed
真核生物的核糖体生物发生涉及到类似200个组装因子，但这些如何有助于核糖体成熟知之甚少。在这里，我们确定了一个新生的60 S亚基，积极重塑前核糖体结构的因素网络。在它的中心是Rsa 4，它是产生力的ATP酶真实的的直接底物。我们表明，Rsa4连接到中央突起结合Rp15和核糖体RNA（rRNA）螺旋89的新生肽基转移酶中心（PTC）通过Nsa2。重要的是，Nsa2在螺旋89重新定位到PTC之前结合到螺旋89。基于结构的突变，这些因素揭示了它们的相互作用的核糖体组装的功能的重要性。因此，Rsa 4被紧紧地固定在前核糖体中，可以作为“分配盒”，将重塑能量从真实的传递到发育中的核糖体中。我们认为，一个中继样因子网络耦合到机械酶的战略定位重新定位核糖体成熟过程中的rRNA元件。
Eukaryotic ribosome biogenesis involves similar to 200 assembly factors, but how these contribute to ribosome maturation is poorly understood. Here, we identify a network of factors on the nascent 60S subunit that actively remodels preribosome structure. At its hub is Rsa4, a direct substrate of the force-generating ATPase Real. We show that Rsa4 is connected to the central protuberance by binding to Rp15 and to ribosomal RNA (rRNA) helix 89 of the nascent peptidyl transferase center (PTC) through Nsa2. Importantly, Nsa2 binds to helix 89 before relocation of helix 89 to the PTC. Structure-based mutations of these factors reveal the functional importance of their interactions for ribosome assembly. Thus, Rsa4 is held tightly in the preribosome and can serve as a "distribution box," transmitting remodeling energy from Real into the developing ribosome. We suggest that a relay-like factor network coupled to a mechano-enzyme is strategically positioned to relocate rRNA elements during ribosome maturation.