Bhattacharyya Debmalya, Morris Mark J, Kharel Prakash, Mirihana Arachchilage Gayan, Fedeli Katy M, Basu Soumitra
Northeast Ohio Regional Sewer District, Cuyahoga Heights, OH, 44125, USA.
Department of Chemistry and Biochemistry, Kent State University, Kent, OH, 44242, USA.
Biochimie. 2017 Jun;137:147-150. doi: 10.1016/j.biochi.2017.03.007. Epub 2017 Mar 16.
RNA domain swapping typically demonstrates conservation of the native function of the domain in a non-native context. In contrast, we employed RNA engineering to demonstrate deviation of G-quadruplex (GQ) function that is contingent upon its context dependent location, which is opposite to their native functional role. Known translation repressing RNA GQs were engineered into human VEGF IRES A replacing the endogenous GQ domain essential for translation. Alternatively, the translation inhibitory GQ motif within the 5'-UTR of MT3-MMP mRNA was replaced with two known GQ motifs that are essential for translation. The results indicate that the engineered GQ domains can adopt GQ structures in a foreign environment with a functional role reversal to accommodate the need of the endogenous swapped motifs. The observations establish the functionality and context dependent modularity of RNA GQ structures.
RNA结构域交换通常表明在非天然环境中该结构域的天然功能得以保留。相比之下，我们利用RNA工程技术证明了G-四链体（GQ）功能会因其依赖于上下文的位置而发生偏差，这与其天然功能作用相反。已知的具有翻译抑制作用的RNA GQ被设计到人类血管内皮生长因子内部核糖体进入位点（VEGF IRES A）中，取代了对翻译至关重要的内源性GQ结构域。或者，MT3-MMP mRNA 5'-非翻译区（UTR）内的翻译抑制性GQ基序被两个对翻译至关重要的已知GQ基序所取代。结果表明，工程化的GQ结构域能够在外部环境中形成GQ结构，其功能作用发生反转以适应内源性交换基序的需求。这些观察结果确立了RNA GQ结构的功能性和依赖于上下文的模块化特性。
