Biochemistry and Structural Biology - a tool
to unlock the secrets of human diseases
The revealing of human genome sequences promises
an unprecedented potential for new discoveries in
biomedical research. Dr. Ban's research focuses
are the determination of 3D protein structures by
X-ray crystallography and NMR studies and the development
of a detection method for protein-protein/DNA interactions
using the biosensor technique. The endeavor
requires coordinated efforts from a number of disciplines
including molecular biology, biochemistry, bioinformatics,
and structural biology. Research topics of
Dr.Ban's laboratory include the followings:
Structural studies on DNA repairing protein
Hereditary nonpolyposis colorectal carcinoma
(HNPCC) is caused by inherited mutations in some
of the gene encoding components of a base-pair mismatch
repair pathway. Dr. Ban and his research staff
are focusing on the continuous structural
studies of three proteins such as MutS, MutL and
MutH as well as their human homologs.
Structural genomics of checkpoint proteins
Understanding the nature of interaction along
the checkpoint cascade would reveal how malfunctions
of those proteins lead to diseases such as human
cancers. "We will target more than 200
proteins involved in the checkpoint pathway,"
explains Dr. Ban.
Structural studies on ssDNA binding transcription
Transcription activation or repression of RNA
polymerase II is often mediated by sequence-specific
DNA-binding proteins (i.e. transcription activating
factors) that respond to extracellular signals by
interacting with critical cis-acting regulatory
elements. Here, they are focusing on structural
studies of three key single-strand binding proteins,
Pura, Purβ, and MSY1 that affect on the human neurodegenerative
Development of electrochemical sensors for
the detection and screening of interacting protein
Biotechnology and medical diagnostics are currently
in need of devices capable of continuously and selectively
detecting biological molecules. "In this
project, electrochemical biosensors detecting specific
DNA interactions, DNA-protein interactions, and/or
protein-protein interactions are under development,"
says Dr. Ban. .
Yang, W., Junop, M. S., Ban, C., Obmolova, G.,
Hsieh, P. (2000). DNA mismatch
repair: From structure
to mechanism. Cold Spring Harbor Symposium on Biological
responses to DNA damage, 65, 225-232.
Obmolova, G., Ban, C., Heish, P., & Yang,
W. (2000). Crystal Structures of Mismatch Repair
Protein MutS and its Complex with a Substrate DNA.
Nature. 407, 703-710.
Ban, C., Junop, M. & Yang, W. (1999). Transformation
of MutL by ATP Binding and Hydrolysis: A Switch
in DNA Mismatch Repair. Cell. 97, 85-97.
Biswas, I., Ban, C., Fleming, K. G. Qin, J.,
Lary J. W., Yphantis D. A., Yang, W. & Hsieh,
P. (1999). Oligomerization of a MutS Mismatch Repair
Protein from Thermus Aquaticus. J. Biol. Chem. 274,
Ban, C., & Yang, W. (1998). Crystal Structure
and ATPase Activity of MutL: Implications for DNA
Repair and Mutagenesis. Cell. 95, 541-552.
Ban, C., & Yang, W. (1998). Structure Basis
of MutH Activation in E. coli. Mismatch Repair and
Relationship of MutH to Restriction Endonucleases.
EMBO J. 17, 1526-1534.