Studies of protein synthesis in the Bacteroidetes

拟杆菌是一类重要的细菌，广泛存在于包括人类在内的哺乳动物的肠道中。类杆菌的基因表达与研究得很好的细菌，如大肠杆菌的基因表达有很大的不同。这个项目将揭示类杆菌中蛋白质制造的独特方式。所获得的知识可能会推动生物技术和医学的进步。该项目还将为本科生、研究生和博士后学生提供研究培训，(Ii)为当地高中生(哥伦布公立学校)提供暑期研究机会，以及(Iii)为俄亥俄州立大学的初级教师提供导师培训。在所有细胞中，核糖体翻译遗传密码，根据信使核糖核酸的信息含量合成蛋白质。翻译速度因信使核糖核酸的翻译起始区(TIR)而异。TIR的内在特征如何决定翻译启动的速度仍然是一个重要的悬而未决的问题。在大肠杆菌等细菌中，TIR的一个众所周知的特征是Shine-Dalgarno(SD)序列，这是一种位于起始密码子上游的富含嘌呤的元件。SD与抗SD(ASD)配对，抗SD(ASD)是16S rRNA 3‘端的一个富含嘧啶的元件，促进启动。最近的研究表明，某些分类类群的细菌，如拟杆菌，在其mRNA中缺乏SD序列。然而，它们的核糖体保留了保守的ASD。该项目旨在利用强生黄杆菌作为模式生物，阐明类杆菌中蛋白质合成的独特方面。具体地说，这项工作将解决(I)核糖体的哪些成分控制ASD-mRNA配对，(Ii)启动复合体是如何在强氏杆菌中形成的，(Iii)ASD是否在核糖体组装中发挥作用，以及(Iv)释放因子RF2的自动调节如何在约翰氏杆菌中发生。这一结果将为不同细菌中的翻译启动、程序化框架转移和核糖体组装机制提供基本的见解。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The Bacteroidetes represent an important group of bacteria, well represented in intestinal tracts of mammals, including humans. Gene expression in the Bacteroidetes differs substantially from that of well-studied bacteria, such as Escherichia coli. This project will reveal the distinct manner in which proteins are made in the Bacteroidetes. The knowledge gained may spur advances in biotechnology and medicine. This project will also provide (i) research training for undergraduate, graduate, and postdoctoral students, (ii) summer research opportunities for local high school students (Columbus Public Schools), and (iii) mentorship training for junior faculty at Ohio State University.In all cells, ribosomes translate the genetic code, synthesizing proteins based on the information content of mRNA. The rate of translation varies dramatically, depending on the translation initiation region (TIR) of mRNA. How intrinsic features of the TIR govern the rate of translation initiation remains an important open question. In bacteria such as E. coli, one well-known feature of the TIR is the Shine-Dalgarno (SD) sequence, a purine-rich element that lies just upstream from the start codon. The SD pairs with the anti-SD (ASD), a pyrimidine-rich element at the 3’ end of the 16S rRNA, to promote initiation. Recent studies have shown that certain taxonomic groups of bacteria, such as the Bacteroidetes, lack SD sequences in their mRNA. Yet, their ribosomes retain the conserved ASD. The project aims to elucidate the unique aspects of protein synthesis in the Bacteroidetes, using Flavobacterium johnsoniae as a model organism. Specifically, the work will address (i) which components of the ribosome govern ASD-mRNA pairing, (ii) how initiation complex formation occurs in F. johnsoniae, (iii) whether the ASD plays a role in ribosome assembly, and (iv) how autoregulation of release factor RF2 occurs in F. johnsoniae. The results will provide fundamental insight on mechanisms of translation initiation, programmed frameshifting, and ribosome assembly in diverse bacteria.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.