MOTIVATION: Expanding research highlights the importance of guanine quadruplex structures. Therefore, easy-accessible tools for quadruplex analyses in DNA and RNA molecules are important for the scientific community. RESULTS: We developed a web version of the G4Hunter application. This new web-based server is a platform-independent and user-friendly application for quadruplex analyses. It allows retrieval of gene/nucleotide sequence entries from NCBI databases and provides complete characterization of localization and quadruplex propensity of quadruplex-forming sequences. The G4Hunter web application includes an interactive graphical data representation with many useful options including visualization, sorting, data storage and export. AVAILABILITY AND IMPLEMENTATION: G4Hunter web application can be accessed at: http://bioinformatics.ibp.cz. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

ARNA Laboratory Inserm U1212 CNRS UMR5320 IECB Université de Bordeaux Pessac France

Brno University of Technology Technicka 2896 2 61969 Brno Czech Republic

Department of Biology and Ecology Faculty of Science University of Ostrava Ostrava Czech Republic

Department of biophysical chemistry and molecular oncology Institute of Biophysics Academy of Sciences of the Czech Republic Brno Czech Republic

Department of Informatics Mendel University in Brno Brno Czech Republic

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