Research Awards
Michael G. Rosenfeld, M.D.
University of California, San Diego
"MeCP2 and CoREST Target Genes in Developing CNS"
2-Year Award: $99,946
Research Sponsor: The Coca- Cola Company
Final Report (November 2005)
Defining the molecular epigenetic strategies that underlie neurodevelopment is a central problem in contemporary molecular neurobiology, and critical to understanding new degenerative diseases. The ability to effectively perform the analyses required to decipher this code during development in a mouse model system depends, in part, on an approach that can accurately locate all DNA binding factors, factor-modifying enzymes, and all coactivators and corepressors using the limited quantity of tissue that is available. We first successfully generated a human 20,000K array of 40 mer oligonucleotides representing human promoters, for use in a "location" analysis using a new strategy referred to as ChIP-DASL-chip array, and demonstrated the efficacy of the technology works at the 20K primer pair level, providing clear results. We have initially applied the technology to the study of an aspect of transcriptional activation/repression events including the study of the CoREST/StBP complex with the 20K array. Tiling a number of genomic loci have revealed that promoters can be thought of in "cohorts" that use similar but distinct, cofactors/modifications, documenting a diversity of epigenetic behavior in control of specific target genes. Based on the hypothesis that histone modifications are a "code, and consistent with the prediction that the balance between activation and repression is reflected in the methylation status of histone H3, we found that activated promoters can exhibit the presence of tri-Me H3K4 in 90% of the promoters, but it does not determine whether a gene is active. Silenced genes exhibit tri-Me H3K9 on their promoters. Thus, a full 10% of promoters harboring the tri-Me H3K4 mark remain Pol II-negative. This platform has now permitted us to look at CoREST as an associated initial evaluation of demethylase and several methyltransferases. CoREST, which as a corepressor of REST target genes, can also employ MeCP2 in repression events. Our data have provided insights into critical aspects of gene regulation, indicating that components of REST-mediated gene silencing events exert a separate, broader role in modulating activation of gene expression programs revealing the multiple, functionally distinct roles of components of the CoREST/CtBP complex. This link between gene activation/repression events involving a specific demethylase/CoREST complex provides a new way to explore an aspect of MeCP2-dependent events in gene regulation.
Michael G. Rosenfeld, M.D.University of California, San Diego
"MeCP2 and CoREST Target Genes in Developing CNS"
2-Year Award: $99,946
Research Sponsor: The Coca- Cola Company
Final Report (November 2005)
Defining the molecular epigenetic strategies that underlie neurodevelopment is a central problem in contemporary molecular neurobiology, and critical to understanding new degenerative diseases. The ability to effectively perform the analyses required to decipher this code during development in a mouse model system depends, in part, on an approach that can accurately locate all DNA binding factors, factor-modifying enzymes, and all coactivators and corepressors using the limited quantity of tissue that is available. We first successfully generated a human 20,000K array of 40 mer oligonucleotides representing human promoters, for use in a "location" analysis using a new strategy referred to as ChIP-DASL-chip array, and demonstrated the efficacy of the technology works at the 20K primer pair level, providing clear results. We have initially applied the technology to the study of an aspect of transcriptional activation/repression events including the study of the CoREST/StBP complex with the 20K array. Tiling a number of genomic loci have revealed that promoters can be thought of in "cohorts" that use similar but distinct, cofactors/modifications, documenting a diversity of epigenetic behavior in control of specific target genes. Based on the hypothesis that histone modifications are a "code, and consistent with the prediction that the balance between activation and repression is reflected in the methylation status of histone H3, we found that activated promoters can exhibit the presence of tri-Me H3K4 in 90% of the promoters, but it does not determine whether a gene is active. Silenced genes exhibit tri-Me H3K9 on their promoters. Thus, a full 10% of promoters harboring the tri-Me H3K4 mark remain Pol II-negative. This platform has now permitted us to look at CoREST as an associated initial evaluation of demethylase and several methyltransferases. CoREST, which as a corepressor of REST target genes, can also employ MeCP2 in repression events. Our data have provided insights into critical aspects of gene regulation, indicating that components of REST-mediated gene silencing events exert a separate, broader role in modulating activation of gene expression programs revealing the multiple, functionally distinct roles of components of the CoREST/CtBP complex. This link between gene activation/repression events involving a specific demethylase/CoREST complex provides a new way to explore an aspect of MeCP2-dependent events in gene regulation.