Structure and decoy-mediated inhibition of the SOX18/Prox1-DNA interaction

Miriam Klaus, Nina Prokoph, Mathias Girbig, Xuecong Wang, Yong Heng Huang, Yogesh Srivastava, Linlin Hou, Kamesh Narasimhan, Prasanna Kolatkar, Mathias Francois, Ralf Jauch

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23 Citations (Scopus)


The transcription factor (TF) SOX18 drives lymphatic vessel development in both embryogenesis and tumour-induced neo-lymphangiogenesis. Genetic disruption of Sox18 in a mouse model protects from tumour metastasis and established the SOX18 protein as a molecular target. Here, we report the crystal structure of the SOX18 DNA binding high-mobility group (HMG) box bound to a DNA element regulating Prox1 transcription. The crystals diffracted to 1.75Å presenting the highest resolution structure of a SOX/DNA complex presently available revealing water structure, structural adjustments at the DNA contact interface and non-canonical conformations of the DNA backbone. To explore alternatives to challenging small molecule approaches for targeting the DNA-binding activity of SOX18, we designed a set of five decoys based on modified Prox1-DNA. Four decoys potently inhibited DNA binding of SOX18 in vitro and did not interact with non-SOX TFs. Serum stability, nuclease resistance and thermal denaturation assays demonstrated that a decoy circularized with a hexaethylene glycol linker and terminal phosphorothioate modifications is most stable. This SOX decoy also interfered with the expression of a luciferase reporter under control of a SOX18-dependent VCAM1 promoter in COS7 cells. Collectively, we propose SOX decoys as potential strategy for inhibiting SOX18 activity to disrupt tumour-induced neo-lymphangiogenesis.

Original languageEnglish
Pages (from-to)3922-3935
Number of pages14
JournalNucleic Acids Research
Issue number8
Publication statusPublished - 5 May 2016


ASJC Scopus subject areas

  • Genetics

Cite this

Klaus, M., Prokoph, N., Girbig, M., Wang, X., Huang, Y. H., Srivastava, Y., Hou, L., Narasimhan, K., Kolatkar, P., Francois, M., & Jauch, R. (2016). Structure and decoy-mediated inhibition of the SOX18/Prox1-DNA interaction. Nucleic Acids Research, 44(8), 3922-3935.