Dr. Ta-Chau Chang (Biophysics and Bioanalytical Technology)
Tel of Office:
+886-2-2366-8231
Latest Research Work
M.H. Kuo, Z.-F. Wang, T.-Y. Tseng, M.-H. Li, S.-T. Hsu, J.-J. Lin, T.-C. Chang*
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 137(1), 210–218 (2015).

The role of G-quadruplexes (G4s) in biological systems has been widely studied. It is found that they have an important function in gene transcription and regulation. In this work, we have identified two topologies of hairpin and G4 structures formed by a native G-rich sequence (WT22: 5′-GGGCCACCGGGCAGGGGGCGGG-3′) from the WNT1 promoter region using nuclear magnetic resonance (NMR) spectroscopy. With the help of site-specific isotope labeling, the topologies of these two structures are unambiguously characterized. Circular dichroism and NMR results are analyzed to determine the kinetics associated with the potassium ion-induced hairpin-to-G4 transition, which is very slow—on the time scale of 4800 s—compared to the previously reported folding kinetics of G4 formation. In addition, the free energies of the unfolding of these two structures are obtained using differential scanning calorimetry. Combining the kinetic and thermodynamic data, we have established the free energy landscape of this two-state folding system. Considering that similar conformational change may exist in other native G-rich sequences, this work highlights an important hairpin to G4 conformational transition which can be used in manipulation of gene regulation or ligand modulation in vivo.
Now at:
People / Faculty / Ta-Chau Chang
Copyright©2012 Institute of Atomic and Molecular Sciences, Academia Sinica
|
Mobile Version
Address: No. 1, Roosevelt Rd., Sec. 4, Taipei, 106319, Taiwan
P.O. Box 23-166 Taipei National Taiwan University, Taipei City, 106923, Taiwan
Tel: 886-2-2362-0212 Fax:886-2-2362-0200 E-mail:
iamspublic@gate.sinica.edu.tw
Latest update 2025-04-30 14:15:19