TY - JOUR
T1 - PDGFR-β Promoter Forms a Vacancy G-Quadruplex that Can Be Filled in by dGMP
T2 - Solution Structure and Molecular Recognition of Guanine Metabolites and Drugs
AU - Wang, Kai Bo
AU - Dickerhoff, Jonathan
AU - Wu, Guanhui
AU - Yang, Danzhou
N1 - Funding Information:
This research was supported by the National Institutes of Health R01CA177585 (DY), P30CA023168 (Purdue Center for Cancer Research), and the Deutsche Forschungsgemeinschaft (German Research Foundation) Projektnummer 427347592 (JD). We thank Dr. Clement Lin for his comments and help on NMR experiments. We thank Dr. Lan Chen at Chemical Genomics Facility, Purdue Institute for Drug Discovery at Purdue University for helping on MST experiments.
Publisher Copyright:
© 2020 American Chemical Society.
PY - 2020/3/18
Y1 - 2020/3/18
N2 - Aberrant expression of PDGFR-β is associated with a number of diseases. The G-quadruplexes (G4s) formed in PDGFR-β gene promoter are transcriptional modulators and amenable to small molecule targeting. The major G4 formed in the PDGFR-β gene promoter was previously shown to have a broken G-strand. Herein, we report that the PDGFR-β gene promoter sequence forms a vacancy G-quadruplex (vG4) which can be filled in and stabilized by physiologically relevant guanine metabolites, such as dGMP, GMP, and cGMP, as well as guanine-derivative drugs. We determined the NMR structure of the dGMP-fill-in PDGFR-β vG4 in K+ solution. This is the first structure of a guanine-metabolite-fill-in vG4 based on a human gene promoter sequence. Our structure and systematic analysis elucidate the contributions of Hoogsten hydrogen bonds, sugar, and phosphate moieties to the specific G-vacancy fill-in. Intriguingly, an equilibrium of 3′- and 5′-end vG4s is present in the PDGFR-β promoter sequence, and dGMP favors the 5′-end fill-in. Guanine metabolites and drugs were tested and showed a conserved selectivity for the 5′-vacancy, except for cGMP. cGMP binds both the 3′- and 5′-end vG4s and forms two fill-in G4s with similar population. Significantly, guanine metabolites are involved in many physiological and pathological processes in human cells; thus, our results provide a structural basis to understand their potential regulatory functions by interaction with promoter vG4s. Moreover, the NMR structure can guide rational design of ligands that target the PDGFR-β vG4.
AB - Aberrant expression of PDGFR-β is associated with a number of diseases. The G-quadruplexes (G4s) formed in PDGFR-β gene promoter are transcriptional modulators and amenable to small molecule targeting. The major G4 formed in the PDGFR-β gene promoter was previously shown to have a broken G-strand. Herein, we report that the PDGFR-β gene promoter sequence forms a vacancy G-quadruplex (vG4) which can be filled in and stabilized by physiologically relevant guanine metabolites, such as dGMP, GMP, and cGMP, as well as guanine-derivative drugs. We determined the NMR structure of the dGMP-fill-in PDGFR-β vG4 in K+ solution. This is the first structure of a guanine-metabolite-fill-in vG4 based on a human gene promoter sequence. Our structure and systematic analysis elucidate the contributions of Hoogsten hydrogen bonds, sugar, and phosphate moieties to the specific G-vacancy fill-in. Intriguingly, an equilibrium of 3′- and 5′-end vG4s is present in the PDGFR-β promoter sequence, and dGMP favors the 5′-end fill-in. Guanine metabolites and drugs were tested and showed a conserved selectivity for the 5′-vacancy, except for cGMP. cGMP binds both the 3′- and 5′-end vG4s and forms two fill-in G4s with similar population. Significantly, guanine metabolites are involved in many physiological and pathological processes in human cells; thus, our results provide a structural basis to understand their potential regulatory functions by interaction with promoter vG4s. Moreover, the NMR structure can guide rational design of ligands that target the PDGFR-β vG4.
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U2 - 10.1021/jacs.9b12770
DO - 10.1021/jacs.9b12770
M3 - Article
C2 - 32101424
AN - SCOPUS:85081650938
SN - 0002-7863
VL - 142
SP - 5204
EP - 5211
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 11
ER -