Yin Laboratory |research
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Yin Laboratory |research |
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Structural basis for anti-HIV drug toxicity Tremendous success fighting human immunodeficiency virus (HIV) replication and transmission with current antiviral drugs must now be balanced against the severe side effects of these reagents. Antiviral inhibitors of HIV reverse transcriptase interfere with human mitochondrial DNA polymerase leading to cellular and tissue toxicity with respect to key cell biological pathological and pharmacological events. We are
conducting structural studies of human mitochondrial DNA polymerase in
complex with various antiviral inhibitors captured during DNA replication.
Specifically, 1) To elucidate interactions between mitochondrial DNA
polymerase and its processivity factor by determination of a co-crystal
structure of Pol
gA
and Pol gB.
2) To capture Pol
gAB
in the action of replication by determination of Comparison of these structures to the corresponding structures of HIV reverse transcriptase (RT) inhibitors complexes will provide: 1) a framework for understanding the clinical toxicity profile of the various inhibitors, and 2) a rationale for design of HIV-RT inhibitors with minimum adverse reactions. Mechanism for gene expression in mitochondria Mitochondrial dysfunctions have been implicated in numerous human diseases including muscular dystrophy, cardiomyopathy, diabetes and neurodegenerative diseases such as Parkinson’s and Alzheimer’s. Mitochondrial gene expression is essential for the integrity of the organelle. It is also a central event for coupling mitochondrial gene transcription with DNA replication and protein translation. Mitochondrial transcription machinery consists of a bacteriophage-like RNA polymerase and a set of transcription factors. However, unlike its bacteriophage ancestor, the mitochondrial RNA polymerase has lost the ability to independently sustain transcription reaction and relies a set the transcription factors for full activity. Despite the importance of mitochondrial transcription, the knowledge of mitochondrial gene expression is incomplete, no structural or systematic kinetic studies of the mitochondrial transcription machinery are available to understand the interaction between the polymerase and the factors in controlling gene expression. We are conducting research to understand the structural and functional aspects of gene expression in mitochondria. We are trying to address questions as 1) how dose the phage-like, self-sufficient RNA transcription system evolved to be regulated by a set of transcription factors; 2) structural basis for collective and individual roles in promoter recognition and unwinding by the RNA polymerase and transcription factors; and 3) Determine the function roles of Rpo41 and MTF1 in de novo RNA synthesis. Bioengineering of T7 RNA polymerase for new functions
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This site was last updated 12/06/07
complexes structures of Pol
T7
RNA polymerase exhibits an amazing structural flexibility as it undergoes
large scale refolding and conformational changes when transitions from
initiation to elongation phase during a transcription reaction (Figure on
the left). Our research focuses on 1) investigating the folding
pathways; 2) engineering T7 RNAP to gain new functions for RNA synthesis,
and 3) transcription termination.