Unknown

Dataset Information

0

NMR structural study on the self-trimerization of d(GTTAGG) into a dynamic trimolecular G-quadruplex assembly preferentially in Na+ solution with a moderate K+ tolerance.


ABSTRACT: Vast G-quadruplexes (GQs) are primarily folded by one, two, or four G-rich oligomers, rarely with an exception. Here, we present the first NMR solution structure of a trimolecular GQ (tri-GQ) that is solely assembled by the self-trimerization of d(GTTAGG), preferentially in Na+ solution tolerant to an equal amount of K+ cation. Eight guanines from three asymmetrically folded strands of d(GTTAGG) are organized into a two-tetrad core, which features a broken G-column and two width-irregular grooves. Fast strand exchanges on a timescale of second at 17°C spontaneously occur between folded tri-GQ and unfolded single-strand of d(GTTAGG) that both species coexist in dynamic equilibrium. Thus, this tri-GQ is not just simply a static assembly but rather a dynamic assembly. Moreover, another minor tetra-GQ that has putatively tetrameric (2+2) antiparallel topology becomes noticeable only at an extremely high strand concentration above 18 mM. The major tri-GQ and minor tetra-GQ are considered to be mutually related, and their reversible interconversion pathways are proposed accordingly. The sequence d(GTTAGG) could be regarded as either a reading frame shifted single repeat of human telomeric DNA or a 1.5 repeat of Bombyx mori telomeric DNA. Overall, our findings provide new insight into GQs and expect more functional applications.

SUBMITTER: Jing H 

PROVIDER: S-EPMC7913680 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

altmetric image

Publications

NMR structural study on the self-trimerization of d(GTTAGG) into a dynamic trimolecular G-quadruplex assembly preferentially in Na+ solution with a moderate K+ tolerance.

Jing Haitao H   Fu Wenqiang W   Hu Wenxuan W   Xu Suping S   Xu Xiaojuan X   He Miao M   Liu Yangzhong Y   Zhang Na N  

Nucleic acids research 20210201 4


Vast G-quadruplexes (GQs) are primarily folded by one, two, or four G-rich oligomers, rarely with an exception. Here, we present the first NMR solution structure of a trimolecular GQ (tri-GQ) that is solely assembled by the self-trimerization of d(GTTAGG), preferentially in Na+ solution tolerant to an equal amount of K+ cation. Eight guanines from three asymmetrically folded strands of d(GTTAGG) are organized into a two-tetrad core, which features a broken G-column and two width-irregular groove  ...[more]

Similar Datasets

| S-EPMC434435 | biostudies-literature
| S-EPMC6753160 | biostudies-literature
| S-EPMC1636422 | biostudies-literature
| S-EPMC4900677 | biostudies-literature
| S-EPMC8215082 | biostudies-literature
| S-EPMC3905899 | biostudies-literature
| S-EPMC7263470 | biostudies-literature
| S-EPMC6115404 | biostudies-literature
| S-EPMC3955360 | biostudies-other
| S-EPMC4242248 | biostudies-literature