Hamline, Michelle Yvonne2011-06-222011-06-222011-05https://hdl.handle.net/11299/107820University of Minnesota Ph.D. dissertation. May 2011. Major: Molecular, Cellular, Developmental Biology and Genetics. Advisor:Dr. Vivian June Bardwell. 1 computer file (PDF); vii, 166 pages.The BCL6 transcriptional corepressor (BCOR) is mutated in the human multisystemic developmental disorder Oculofaciocardiodental syndrome (OFCD). The aim of this thesis is to understand the repressive function of BCOR in embryonic development. To accomplish this, BCOR was first tandem affinity purified from human embryonic kidney cells and found to interact with chromatin modifying proteins and several transcription factors, suggesting a molecular mechanism by which BCOR effects repression. In addition, conditional overexpression and null Bcor alleles were created in mice to elucidate the in vivo role of BCOR. The conditional overexpression allele revealed tight control of Bcor transcript levels in B cells and a requirement for proper control of Bcor expression for embryonic viability. The conditional null allele revealed that Bcor is required in neural crest cells for craniofacial development, in hindlimb precursors for proper limb formation, and in cardiovascular progenitors for cardiovascular development and function. These findings provide important insights into the function of BCOR in embryonic development and will facilitate the future diagnosis and treatment of developmental disorders such as OFCD.en-USBCORCardiovascular developmentCraniofacial developmentOculofaciocardiodental syndromeOFCDTranscriptional repressionMolecular, Cellular, Developmental Biology and GeneticsThesis or Dissertation