Martin Wuhr, Princeton University

Martin Wuhr, Princeton University

Butler Seminar Series

Event Date/Location

September 28, 2022 - 12:00 pm to 1:00 pm
Thomas Laboratory 003

Speaker

  • Martin Wuhr photo

    Martin Wuhr

    Assistant Professor of Molecular Biology and the Lewis-Sigler Institute for Integrative Genomics
    Princeton University

    How do molecules organize into living systems?

    We now have a near complete parts list of all the molecules constituting cells. However, we still only poorly understand how all these tiny molecules self-organize into much larger organelles, cells, and organisms. Our group aims to elucidate principles underlying this organization. Specifically, we study how the proteome partitions between nucleus and cytoplasm. We aim to decipher the underlying molecular mechanisms, and ask how different nuclear composition affects biological function. To address these questions we employ and develop mass-spectrometry based proteomics and combine this technology with computational, biochemical, and imaging approaches.  Our main research models are human tissue culture cells and the eggs, cell-free extracts, and embryos of the frog Xenopus laevis.

Topic

Development of Proteomics Technology and its Application to Study Cellular Organization

Global studies of proteins via mass spectrometry lag behind other omics approaches. I will present an overview of our efforts to close this gap, simultaneously improving precision, accuracy, and sensitivity. I will outline ongoing work which could enable quantitative proteomics data from entry-level mass spectrometers, with the general aim to “democratize” proteomics. To illustrate these approaches, I will discuss how we have used them for systems-level analysis of cellular organization. Specifically, I will focus on how the nuclear proteome changes in early development. We quantify changes in the nuclear proteome during early development and find that nuclear proteins, such as transcription factors and RNA polymerases, enter nuclei sequentially. Moreover, we find that the timing of nuclear proteins’ access to the genome corresponds to the timing of downstream gene activation. We show that the affinity of proteins to importin is a major determinant in the timing of protein entry into embryonic nuclei. Thus, we propose a mechanism by which embryos encode the timing of gene expression in early development via biochemical affinities. These results demonstrate the potential of quantitative proteomics and our techniques to address systems-level questions about protein dynamics in various biological contexts.

Audience

Free and open to the university community and the public.

Host

Department of Molecular Biology