Sabine Petry

Position
Associate Professor of Molecular Biology
Office Phone
Office
415 Schultz Laboratory
Education

M.S., Biochemistry, Goethe University, Frankfurt am Main, Germany, 2003

Ph.D., Biochemistry, University of Cambridge, UK, 2007

Advisee(s):
Bio/Description

Honors and Awards

  • Packard Fellowship, David and Lucile Packard Foundation, 2014-2019
  • Pew Scholar in the Biomedical Sciences, 2014-2016
  • Kimmel Scholar for Cancer Research, 2014-2016
  • NIH Pathway to Independence Award, 2012-2016
  • Postdoctoral HHMI Fellow of the Life Science Research Foundation, 2009-2011
  • EMBO Long-term Fellowship for Postdoctoral Research, 2008
  • FEBS Young Scientist Prize, 2007
  • Max Perutz Student Price for Outstanding Research, 2005

Affiliations

  • Associate Professor, Department of Molecular Biology
  • Associated Faculty, Department of Chemical and Biological Engineering
  • Associated Faculty, Department of Chemistry
  • Associated Faculty, Omenn-Darling Bioengineering Institute

Research Interests

Molecular Architecture and Function of the Microtubule Cytoskeleton.

 

 

Acentrosomal spindles are assembled around microprinted chromatin-beads
Acentrosomal spindles are assembled around microprinted chromatin-beads upon addition of Xenopus egg extract depleted of augmin. Imaging was performed with confocal laser scanning microscopy. Spindles forming in augmin-depleted extracts showed reduced rates of MT formation and were predominantly multipolar, revealing a function of augmin in stabilizing the bipolar shape of the acentrosomal meiotic spindle (Petry et al., PNAS 2011).
We are interested in understanding how cells acquire their shape, position organelles, move materials, and segregate chromosomes during cell division. These features are essential for life and organized by the microtubule cytoskeleton, which resembles the skeletal system that supports our human body. Each cell type and shape requires a specific microtubule architecture. For instance, long and bundled microtubules make up the axonal extensions of a nerve cell that can reach up to 1 meter in length, whereas a spherical microtubule network renders a lymphocyte perfectly round. In contrast to the human skeleton, the microtubule cytoskeleton is also highly dynamic. Most cells regularly undergo cell division, during which the cell-type specific interphase microtubule network is completely disassembled and replaced by short and dynamic microtubules of the mitotic spindle to capture, align and then segregate chromosomes.
How is a specific microtubule architecture established at the molecular level?

 

 

Microtubules grow off the wall of existing microtubules
Microtubules (red with growing tips in green) grow off the wall of existing microtubules, which is visualized by total internal reflection (TIRF) microscopy. This recently uncovered mechanism, termed branching microtubule nucleation, amplifies microtubules while preserving their polarity and is needed to assemble the mitotic spindle of a dividing cell (Petry et al., Cell 2013).
Microtubules are cylindrical and dynamic polymers that consist of the protein tubulin. The biological function of the microtubule cytoskeleton relies on the precise arrangement of microtubules in the cell. To achieve this organization, microtubule associated proteins generate, sever, polymerize, shrink, bundle, anchor, or move microtubules. We want to understand these functionalities mechanistically and use this insight to explain how they ultimately result in the self-organization of the microtubule cytoskeleton.

We employ two complementary approaches that allow us to both look at structural detail of microtubule effectors and explain their function in the biological context. To study the mechanism by which microtubules are organized at a structural level, we use biophysical methods, electron microscopy and X-ray crystallography. To understand the dynamic assembly of the microtubule cytoskeleton, we combine biochemical and cell biological techniques along with advanced light microscopy methods.

Our goal is to identify and characterize new mechanisms that establish the cellular microtubule architecture. This will ultimately reveal how the microtubule cytoskeleton builds cellular structures to give cells their shape, position organelles, serve as tracks that move materials, generate force for movement, and segregate chromosomes. 

Selected Publications
  1. Thawani A, Kadzik RS, Petry S. XMAP215 is a microtubule nucleation factor that functions synergistically with the γ-tubulin ring complex. Nat Cell Biol. 2018; 20(5):575-585.

  2. Dixit R, Petry S. The life of a microtubule. Mol Biol Cell. 2018; 29(6):689.

  3. Song J-G, King MR, Zhang R, Kadzik RS, Thawani A, Petry S. Mechanism of how augmin directly targets the γ-tubulin ring complex to microtubules. J Cell Biol. 2018; 217(7):2417-2428.

  4. Song J-G, Petry S. Dissecting Protein Complexes in Branching Microtubule Nucleation Using Meiotic Xenopus Egg Extracts. Cold Spring Harb Protoc. 2018.

  5. Rale MJ, Kadzik RS, Petry S. Phase Transitioning the Centrosome into a Microtubule Nucleator. Biochemistry. 2017.