Regulation of epidermal homeostasis by centrosomal proteins

PROJECT SUMMARY This proposal describes a five-year training program to support the development of an academic, physician- scientist with a focus on advancing the understanding of cutaneous inflammatory diseases. The principal investigator has a strong track record of basic science research in the areas of molecular virology, immunology, and cell biology and seeks to enhance her expertise in centrosome, cytoskeletal, and keratinocyte biology. Central to her further training is a proposed mentored research project focusing on the role of centrosomal protein CEP43 in the maintenance of epidermal integrity and its link to immune activation. Keratinocytes prevent epidermal disruption and promote epidermal homeostasis by the formation of a highly organized network supported by specialized cell junctions and adhesion molecules that are supported by the cytoskeleton and organized by the centrosome. The PI presents preliminary data showing that targeted deletion of Cep43 in the epidermis leads to dysregulation of the keratinocyte cytoskeleton and robust psoriasiform rash. These data strongly suggest that the research plan will define new mechanisms linking keratinocyte and epidermal integrity to immune activation by focusing on the centrosome and the centrosomal protein CEP43 in particular, and that this approach will ultimately lead to the identification of novel pathways contributing to epidermal homeostasis that could serve as therapeutic targets for the treatment of inflammatory skin disease. The specific aims are: (1) Define mechanisms by which CEP43 loss leads to keratinocyte stress and p53 activation, (2) Define mechanisms by which CEP43 loss leads to inflammation and psoriasiform dermatitis. The research design employs cutting- edge techniques and novel animal models. Ultra-expansion microscopy (UExM) will be used for super-resolution imaging of centrosomal and cytoskeletal structures in keratinocytes. Newly created conditional knockout mice enable Cep43 deletion specifically in keratinocytes, followed by phenotypic analyses using histology, transmission electron microscopy, and transcriptomic profiling to assess cellular stress responses and inflammatory pathways. The candidate’s career development plan includes hands-on training in UExM and participation in leadership, mentorship, and grant-writing workshops. Regular mentorship meetings with Dr. Marco Colonna, a world expert in innate immunity, and Dr. Moe R. Mahjoub, a leader in centrosomal and cytoskeletal biology, will provide robust guidance. Washington University in St. Louis provides a supportive environment with state-of-the-art facilities, a collaborative research community, and guaranteed protected research time. This environment, combined with strong mentorship and advanced resources, will enable the candidate to successfully transition to an independent investigator and significantly advance our understanding of cutaneous inflammatory diseases.