Subtopic Deep Dive

G-Quadruplex Molecular Recognition
Research Guide

What is G-Quadruplex Molecular Recognition?

G-Quadruplex Molecular Recognition refers to the biophysical mechanisms by which proteins such as helicases, transcription factors, and nucleases specifically bind and interact with G-quadruplex (G4) DNA structures.

Studies employ techniques like circular dichroism (CD), FRET, and SPR to quantify binding affinities and kinetics of proteins to G4 motifs in telomeres, promoters, and UTRs. Key papers include Kypr et al. (2009) on CD spectroscopy of G4 conformations (1719 citations) and Rhodes and Lipps (2015) reviewing G4 regulatory roles (1471 citations). Over 10 high-citation papers document G4-protein interactions in gene regulation and cancer.

Curated Papers

Key Challenges

Why It Matters

G4 recognition by proteins like BLM helicase influences telomere maintenance and DNA repair, impacting cancer progression (Patel et al., 2007, 876 citations). Transcription factor binding to promoter G4s modulates oncogene expression, offering targets for therapeutics like AS1411 aptamer (Bates et al., 2009, 834 citations). These interactions underpin G4 roles in translation regulation via 5'-UTR RNA G4s (Bugaut and Balasubramanian, 2012, 635 citations).

Key Research Challenges

Quantifying Binding Kinetics

Distinguishing specific G4-protein interactions from non-specific binding requires high-resolution methods like SPR and FRET. Conformational polymorphism complicates affinity measurements (Kypr et al., 2009). Few studies provide kinetic data for helicases like WRN on diverse G4 topologies.

Predicting G4 Propensity

Tools like QGRS Mapper identify potential G4s, but false positives limit recognition studies (Kikin et al., 2006, 992 citations). G4Hunter improves accuracy for in vivo relevance (Bedrat et al., 2016, 673 citations). Validating predictions in cellular contexts remains challenging.

Cation Effects on Stability

Metal cations like K+ and Na+ modulate G4 folding and protein binding, affecting recognition (Bhattacharyya et al., 2016, 612 citations). Diverse loop sequences yield hybrid topologies hard to predict. Integrating cation effects into binding models is unresolved.

Essential Papers

Circular dichroism and conformational polymorphism of DNA

Jaroslav Kypr, Iva Kejnovská, Daniel Renčiuk et al. · 2009 · Nucleic Acids Research · 1.7K citations

Here we review studies that provided important information about conformational properties of DNA using circular dichroic (CD) spectroscopy. The conformational properties include the B-family of st...

G-quadruplexes and their regulatory roles in biology

Daniela Rhodes, Hans J. Lipps · 2015 · Nucleic Acids Research · 1.5K citations

'If G-quadruplexes form so readily in vitro, Nature will have found a way of using them in vivo' (Statement by Aaron Klug over 30 years ago).During the last decade, four-stranded helical structures...

QGRS Mapper: a web-based server for predicting G-quadruplexes in nucleotide sequences

O. Kikin, Lawrence D’Antonio, Paramjeet S. Bagga · 2006 · Nucleic Acids Research · 992 citations

The quadruplex structures formed by guanine-rich nucleic acid sequences have received significant attention recently because of growing evidence for their role in important biological processes and...

Nanomaterials Based on DNA

Nadrian C. Seeman · 2010 · Annual Review of Biochemistry · 986 citations

The combination of synthetic stable branched DNA and sticky-ended cohesion has led to the development of structural DNA nanotechnology over the past 30 years. The basis of this enterprise is that i...

Human telomere, oncogenic promoter and 5'-UTR G-quadruplexes: diverse higher order DNA and RNA targets for cancer therapeutics

Dinshaw J. Patel, Anh Tuân Phan, Vitaly Kuryavyi · 2007 · Nucleic Acids Research · 876 citations

Guanine-rich DNA sequences can form G-quadruplexes stabilized by stacked G-G-G-G tetrads in monovalent cation-containing solution. The length and number of individual G-tracts and the length and se...

Thrombin-binding DNA aptamer forms a unimolecular quadruplex structure in solution.

Román F. Macaya, Peter Schultze, F. W. Smith et al. · 1993 · Proceedings of the National Academy of Sciences · 869 citations

We have used two-dimensional 1H NMR spectroscopy to study the conformation of the thrombin-binding aptamer d(GGTTGGTGTGGTTGG) in solution. This is one of a series of thrombin-binding DNA aptamers w...

Discovery and development of the G-rich oligonucleotide AS1411 as a novel treatment for cancer

Paula J. Bates, Damian A. Laber, Donald M. Miller et al. · 2009 · Experimental and Molecular Pathology · 834 citations

Reading Guide

Foundational Papers

Start with Kypr et al. (2009) for CD-based G4 conformational analysis, Macaya et al. (1993) for NMR structure of thrombin-binding aptamer, and Patel et al. (2007) for diverse G4 topologies in telomeres and promoters.

Recent Advances

Study Rhodes and Lipps (2015) for G4 regulatory roles, Bedrat et al. (2016) for G4Hunter prediction tool, and Bhattacharyya et al. (2016) for cation effects on stability.

Core Methods

Core techniques include CD spectroscopy (Kypr et al., 2009), NMR for atomic structures (Macaya et al., 1993), computational prediction (Kikin et al., 2006; Bedrat et al., 2016), and biophysical assays like FRET/SPR for kinetics.

How PapersFlow Helps You Research G-Quadruplex Molecular Recognition

Discover & Search

Research Agent uses searchPapers('G-quadruplex protein binding helicase') to retrieve 50+ papers, then citationGraph on Rhodes and Lipps (2015) to map regulatory networks, and findSimilarPapers for helicase-specific G4 binders. exaSearch uncovers unpublished preprints on WRN-G4 kinetics.

Analyze & Verify

Analysis Agent applies readPaperContent on Kypr et al. (2009) to extract CD spectra data, verifyResponse with CoVe against FRET datasets, and runPythonAnalysis to plot binding curves using NumPy/pandas. GRADE grading scores evidence strength for SPR kinetics claims.

Synthesize & Write

Synthesis Agent detects gaps in helicase-G4 kinetics via contradiction flagging across papers, then Writing Agent uses latexEditText for structural diagrams, latexSyncCitations for 20+ references, and latexCompile to generate a review manuscript. exportMermaid visualizes G4 topologies and protein interfaces.

Use Cases

"Analyze BLM helicase binding affinities to telomeric G4s from recent papers"

Research Agent → searchPapers → Analysis Agent → runPythonAnalysis (pandas aggregation of Kd values from 10 papers) → matplotlib binding isotherm plots.

"Draft LaTeX figure of thrombin aptamer G4 structure with citations"

Synthesis Agent → gap detection → Writing Agent → latexGenerateFigure (NMR structure from Macaya et al., 1993) → latexSyncCitations → latexCompile → PDF output.

"Find GitHub repos with G4 prediction code linked to QGRS Mapper papers"

Research Agent → paperExtractUrls (Kikin et al., 2006) → paperFindGithubRepo → Code Discovery → githubRepoInspect → runnable Python G4 scanner.

Automated Workflows

Deep Research workflow scans 50+ G4 papers via searchPapers → citationGraph → structured report on recognition motifs. DeepScan applies 7-step CoVe analysis to verify BLM-WRN binding claims with GRADE scoring. Theorizer generates hypotheses on nucleolin-G4 roles from Rhodes and Lipps (2015) literature synthesis.

Try Doxa for G-Quadruplex Molecular Recognition Research

Frequently Asked Questions

What defines G-quadruplex molecular recognition?

It encompasses protein binding to G4 structures via biophysical methods like CD, NMR, FRET, and SPR to measure kinetics and specificity (Kypr et al., 2009).

What are key methods for studying G4-protein interactions?

CD spectroscopy distinguishes G4 conformations (Kypr et al., 2009), NMR resolves thrombin aptamer structure (Macaya et al., 1993), and SPR/FRET quantify kinetics.

What are seminal papers on G4 recognition?

Kypr et al. (2009, 1719 citations) on CD of G4s; Rhodes and Lipps (2015, 1471 citations) on biological roles; Patel et al. (2007, 876 citations) on telomeric G4s.

What open problems exist in G4 recognition?

In vivo validation of predicted G4-protein pairs, cation-dependent topology effects on binding (Bhattacharyya et al., 2016), and kinetics for diverse cellular proteins.