smFRET reveals DHX36 repetitive binding,not unfolding,of G-quadruplexes

Hai-Lei Guo; Na-Nv Liu; Xu-Guang Xi

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arXiv · 2106.07858

smFRET reveals DHX36 repetitive binding,not unfolding,of G-quadruplexes

Hai-Lei Guo·Na-Nv Liu·Xu-Guang Xi

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Abstract

Our data challenge Chen et al.'s interpretation of smFRET results, i.e. the repetitive unfolding of G4 with one-base translocations. We believe that the observed oscillatory curve represents the alternate binding of DHX36 to the 3' and 5'G-tetrad of G4s, rather than the repetitive unfolding between the canonical and the transformed non-canonical G4s. Noteworthily, our results reported here also call into question the previously published smFRET data of helicase-mediated G4 unfolding. Therefore,discriminating the smFRET signal of repetitive binding from that of unfolding is very important to avoid misinterpreting smFRET results.

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Hai-Lei Guo, Na-Nv Liu, Xu-Guang Xi. 2021-06-15. smFRET reveals DHX36 repetitive binding,not unfolding,of G-quadruplexes. https://arxiv.org/abs/2106.07858

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