**4. Materials and Methods**

Experimental details are provided in the Supplementary Materials. Briefly, ensemble fluorescence anisotropy and fluorescence electrophoretic mobility assay (fEMSA) experiments were performed in Buffer E (20 mM Tris, 50 mM NaCl, 0.10 mg/mL BSA, 5% glycerol, 0.1 mM DTT/0.05 mM TCEP, pH 8) with Alexa Fluor-647 labeled dsDNANANOG (Forward: ACTTTTGCATTACAATG; 17 bp). smFRET experiments were performed in the same buffer using a custom-built confocal fluorescence microscopy set up as described previously [28].

**Supplementary Materials:** Supplementary materials can be found at http://www.mdpi.com/1422-0067/19/12/ 3865/s1.

**Author Contributions:** A.C.M.F. and J.C.F. conceived and designed the experiments; M.M.M., P.S.T., K.-J.C., A.C.M.F. and J.C.F. performed the experiments; M.M.M., P.S.T., A.C.M.F. and J.C.F. analyzed the data; M.M.M., A.C.M.F. and J.C.F. wrote the paper.

**Funding:** This work was supported by laboratory startup funds from the Baylor College of Medicine (A.C.M.F. and J.C.F.). J.C.F. is supported by R01 GM122763 from the NIGMS, NIH.

**Conflicts of Interest:** The authors declare no conflict of interest.
