The primary goal of this research is to understand the mechanisms by which gene expression is regulated within the cell. DNA is the long-term storage unit for genetic information, providing instructions for cellular and life functions. Access to different genetic regions is partially regulated by reversible chemical changes to localized regions of the DNA, defined as epigenetic modifications. This project evaluates the role of a small family of proteins, the ZBTB family, that are important in making these epigenetic modifications. The broader impacts for this project include two major aspects: First, the training of graduate students in an interdisciplinary research program that utilizes a broad spectrum of techniques to identify and characterize the three ZBTB. Second, this project includes the development of biochemical and DNA-focused hands-on and inquiry-based activities at The Leonardo, a museum in downtown Salt Lake City. In addition to the broader public, The Leonardo accommodates a significant number of students from underrepresented and underserved groups from Salt Lake Valley schools. It is well recognized that the interest of a child in science is best instilled at an early and impressionable age, and it is expected that development and implementation of hands-on activities will have a long-term significant impact on the state's diversity growth in STEM areas.
DNA methylation is one form of epigenetic modification. While insight into how the DNA methylation mark is established and removed has been gained, there is only minimal knowledge for the mechanisms by which methyl-CpG binding proteins (MBPs),read DNA methylation marks and translate this information into a specific transcriptional outcome, particularly for the ZBTB MBPs. An understanding for how the ZBTB MBPs modulate transcription is complicated by the fact that they exhibit bimodal DNA recognition, targeting both methylated and sequence-specific non-methylated DNA sites, which affords them the capability of functioning as both transcriptional repressors and activators. Additionally, each of the ZBTB MBPs can interact with multiple co-repressor/-activator protein complexes at target gene sites. Thus, an understanding for how each of these proteins elicits selectivity for their binding partners is central to discerning their role in transcriptional regulation. To investigate this, a combined in vitro biophysical and in cell approach will be utilized to delineate the mechanisms by which this family of MBPs recognize their DNA and proteins targets. The overall goals are to structurally characterize ZBTB protein:DNA interactions to gain mechanistic insight into how each protein preferentially selects DNA targets; to utilize function-specific mutations to probe the molecular basis for bimodal DNA recognition; and to define protein interactomes for each ZBTB MBP. The outcomes of this research will provide an essential foundation for the larger goal of discerning the full mechanisms by which each member of this under studied family of ZBTB MBPs elicits selective gene targeting, recruits specific protein complexes to the target site and alters transcription to provide a particular cellular function.
