Medical Student Research Fellowship for Summer 2011

Mentor: Drs. David Chuang and R. Max Wynn                        
Department: Biochemistry
Room number: E5.302      
Mail Code: 9038                  
Phone number: 214-648-2457 or 214-648-8693          
E-mail: David.chuang@utsouthwestern.edu or Richard.wynn@utsouthwestern.edu
                       
Project title:  Mitochondrial Protein Kinases                  

Human subjects IRB approved project number (where applicable): N/A     

Animal subjects IRB approved project number (where applicable): N/A     

Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects) 

Project Type: Basic Research with emphasis on cell culture and in vitro assays. Expression and purification of branched-chain alpha-ketoacid dehydrogenase complex (BCKDC) proteins including BCKD kinase (BDK) and cell culture assays for the inhibition of mitochondrial kinase activities by novel small-molecule inhibitors.

Brief Description of Project:

We have determined crystal and solution structures for the three catalytic components (E1, E2 and E3) and the E2 domains of the mammalian branched-chain alpha-ketoacid dehydrogenase complex (BCKDC). We have also deciphered the structure of rat BDK (BCKD kinase), and described the structural basis for the regulation of BCKDC by the phosphorylation (inactivation) /dephosphorylation (reactivation) cycle. We will continue to dissect the structure and function of BCKDC as well as the structural and biochemical mechanisms for Maple Syrup Urine Disease (MSUD). The scope will be extended to the development of a new generation of efficient BDK inhibitors as a novel therapeutic approach to MSUD. The project aims to develop novel small-molecule inhibitors for BDK as a therapeutic approach to E2-affected MSUD with intermediate and thiamine-responsive phenotypes.

Previous Research Activities or Publications with Medical Students:

Davie, J.R., R.M. Wynn, R.P. Cox and D.T. Chuang 1992.  Expression and Assembly of a Functional E1 Component (a2b2) of Mammalian Branched-Chain a-Keto Acid Dehydrogenase Complex in E. coli, J. Biol. Chem. 267, 16601-16606.

Davie, J.R., R.M. Wynn, M. Meng, Y.-S. Huang, G. Aalund, D.T. Chuang, and K.S. Lau 1995. Expression and characterization of rat branched-chain a-ketoacid dehydrogenase kinase.  Is it a histidine-protein kinase? J. Biol. Chem. 270, 19861-19867.

Wynn, R.M., J.R. Davie, J. L. Chuang, C.D. Cote, R.P. Cox, and D.T. Chuang 1998. Impaired Assembly of E1 Decarboxylase of the Branched-Chain a-Ketoacid Dehydrogenase Complex in Type IA Maple Syrup Urine Disease.  J. Biol. Chem., 273, 13110-13118.

Wynn, R.M., J.R. Davie J.-L. Song, J.L. Chuang, D.T. Chuang 2000.  Efficient expression of the E1 component of Human BCKD complex in E. coli by co-transformation with chaperonins GroEL and GroES.  In: Methods In Enzymology (Harris, R.A. and Socatch, R. eds.) Academic Press, New York, 179-192.

Chuang, J.L., J.R.Davie, R.M. Wynn, and D.T. Chuang 2000.  Production of recombinant mammalian holo-E2 and E3 and reconstitution of functional BCKD complex with recombinant E1.  In: Methods In Enzymology (Harris, R.A. and Socatch, R. eds) Academic Press, New York, 192-200.

Two additional students have also trained in the lab:

Jun Lee and Aaron Jones-both students worked to help clone the genes for the BCKDC.