K+-responsive off-to-on switching of hammerhead ribozyme through dual G-quadruplex formation requiring no heating and cooling treatment
K+-responsive off-to-on switching of hammerhead ribozyme through dual G-quadruplex formation requiring no heating and cooling treatment
复制标题
K-响应性锤头核酶通过双 G-四链体形成进行开关，无需加热和冷却处理
DOI：
10.1016/j.bbrc.2015.10.173
复制
发表时间：
2015
影响因子：
3.1
通讯作者：
Katahira M
中科院分区：
文献类型：
--
作者：
Yamaoki Y;Nagata T;Mashima T;Katahira M
根据K+改变活性的功能性rna可以感知细胞内（100 mM）和细胞外（5 mM）的K+浓度，并相应地调节其功能。在此之前，我们开发了一种四重锤头核酶（QHR），它的构象变化，从双工到g四工，由K+触发，导致活性的表达。然而，这种QHR需要加热和冷却处理（退火）来诱导K+响应的构象变化和活性。在这里，我们开发了一种新的四重锤头核酶（QHR）系统，不需要退火就能诱导K+响应的构象变化和活性。该系统由QHR和g -四联体形成的互补DNA链（QCS）组成。在没有K+的情况下，QCS与QHR形成双工，抑制了残留活性。当K+浓度升高时，与QHR解离的QCS被困在g -四重体中，QHR形成g -四重体并发挥活性。K+诱导活性提高11.6倍，ec50值为23 mM，而Na+则没有，当活性在细胞内/细胞外环境之间切换时，这是理想的。这是第一个通过“双g -四重体形成系统”激活功能性RNA的报道。
Functional RNAs that switch their activities in response to K+may sense the intracellular (100 mM) and extracellular (5 mM) K+concentrations and regulate their functions accordingly. Previously, we developed a quadruplex hammerhead ribozyme (QHR) whose conformational change, from a duplex to a G-quadruplex, triggered by K+results in expression of the activity. However, this QHR required heating and cooling treatment (annealing) to induce the K+-responsive conformational change and activity. Here, we developed a new quadruplex hammerhead ribozyme (QHR) system that does not require annealing to induce the K+-responsive conformational change and activity. This system is composed of QHR and a G-quadruplex-forming complementary DNA strand (QCS). In the absence of K+, QCS formed a duplex with QHR, which suppressed the residual activity. Upon elevation of the K+concentration, QCS dissociated from QHR was trapped in a G-quadruplex, and then QHR could form a G-quadruplex and exerted the activity. The 11.6-fold higher activity was induced by K+with an EC50value of 23 mM, but not by Na+, which is desirable when the activity switching between the intra-/extracellular environment is aimed at. This is the first report of the activation of functional RNA through a ‘dual G-quadruplex formation system’.