Research Interests

Research in the Amann lab focuses on developing a molecular understanding of the mechanisms underlying cell structure and motility in both eukaryotes and prokaryotes. We are particularly interested in answering the question - How is it that tremendously divergent cells use essentially similar cytoskeletal polymer systems to carry out widely varying physiological tasks? More specifically, we study the mechanisms by which motile eukaryotic cells control the polymerization state of the protein actin and the means by which actin polymerization is translated into the forces that drive motility. More recently, we have begun intensive studies of the actin-like molecules that have just been identified in bacteria. Because almost nothing is known about the biochemical behavior of these molecules, it is currently very difficult to understand how they carry out the functions that affect bacterial physiology and what roles they may play in bacterial pathology. We are addressing this problem by carrying out the first rigorous biochemical characterization of the chromosomally encoded bacterial actins with the hope that we will largely elucidate the means by which these surprisingly complex molecules contribute to bacterial cell biology.

Courses:

L&S 104 - First-Year Interest Group "Critical Thinking"
Zoology 151 - Introductory Biology
Zoology 570 - Cell Biology
Zoology 960 - Seminar in Cell Biology
Anatomy 700 - Cytoskeletal Dynamics

Note to prospective graduate students:

We are actively recruiting ambitious graduate students with a strong interest in biochemical characterization of the cytoskeleton.

Graduate students currently supervised:

Joshua Mayer, 4th year CMB student (joshuamayer@wisc.edu).
   Josh is attempting to identify the first B. subtilis proteins that interact directly with the actin homologue MreB.

Selected Publications

• Perrin, B.J., Amann, K.J., and Huttenlocher, A. (2006) Proteolysis of cortactin by calpain regulates membrane protrusion during cell migration. Molecular Biology of the Cell . 7(1):239-250.

• Maul, R.S., Song, Y., Amann, K.J., Gerbin, S.C., Pollard, T.D., and Chang, D.D. (2003) EPLIN regulates actin dynamics by crosslinking and stabilizing filaments. J. Cell Biol. 160(3): 399-407.

• Amann, K.J., and Pollard, T.D. (2001) Direct real-time observation of actin filament branching mediated by Arp2/3 complex using total internal reflection fluorescence microscopy. Proc. Nat. Acad. Sci. 98(26):15009-15013.

• Volkmann, N., Amann, K.J., Stoilova-McPhie, S., Egile, C., Winter, D.C., Hazelwood, L., Heuser, J.E., Li, R., Pollard, T.D., and Hanein, D. (2001) Structure of the Arp2/3 complex and its actin-bound form at branch junctions. Science . 293(5539):2456-2459.

• Amann, K.J., and Pollard, T.D. (2001) The Arp2/3 complex nucleates actin filament branches from the sides of pre-existing filaments. Nature Cell Biology . 3(3):306-310.

• Amann, K.J., and Pollard, T.D. (2000) Cellular Regulation of Actin Network Assembly. Current Biology. 10(20):R728-730.

• Blanchoin, L.*, Amann, K.J.*, Higgs, H.N., Marchand, J.-B., Kaiser, D.A., and Pollard, T.D. (2000) Direct observation of dendritic actin filament networks nucleated by Arp2/3 complex and WASP/Scar proteins. Nature . 404(6781):1007-1011.
  *These authors contributed equally to this work.

• Amann, K.J., and Pollard, T.D. (2000) Cellular Regulation of Actin Network Assembly. Current Biology . 10(20):R728-730.Amann, K.J., Guo, A. W.-X, and Ervasti, J.M. (1999) Utrophin lacks the rod domain actin binding activity of dystrophin. Journal of Biological Chemistry . 274(50):35375-35380.

• Amann, K.J., Renley, B.A., and Ervasti, J.M. (1998) A cluster of basic repeats in the dystrophin rod domain binds F-actin through an electrostatic interaction. Journal of Biological Chemistry . 273(43): 28419-28423