Aaron Turkewitz, Ph.D.

Primary:

Associate Professor, Molecular Genetics and Cell Biology

Secondary:

Committee on Genetics
Committee on Cellular and Molecular Physiology
Committee on Microbiology
Cancer Research Center
The College

Education:
Degree Year Institution Area
BA
   1981
   Harvard University
   Biochemistry
PhD
   1988
   Harvard University
   Biochemistry & Molecular Biology
Postdoc
1988-1993
UCSF, San Francisco, CA
Cell Biology


Phone: (773) 702-4374
E-Mail: apturkew@uchicago.edu
Address: Room 611A CLSC; 920 E. 58th St.; Chicago, IL 60637
Web page:
 http://mgcb.bsd.uchicago.edu/faculty/turkewitz/index.html

Research Summary

Regulation of protein traffic; exocytosis and endocytosis in protists; evolution.
Our laboratory studies membrane traffic in a somewhat unusual model system, the ciliate Tetrahymena thermophila. Ciliates emerged as an early branch during eukaryotic evolution, and are far more distantly related to humans, for example, than are most organisms being studied by cell biologists. Our interest in these cells stems from the fact that ciliates are unicellular and offer a host of experimental advantages, but at the same time are highly complex and maintain many cellular features that are usually associated with animal cells. In particular, ciliates have a prominent pathway for regulated secretion of polypeptides via dense core granules. Such granules arise by mechanisms that are poorly understood in the mammalian cells in which they have classically been studied. We use a combination of biochemical and genetic approaches, taking advantage of the ability to derive viable Tetrahymena mutants with defects in granule function. Our second major interest is in the complementary process, endocytosis, by which membrane is taken up from the cell surface. Ciliates also appear to maintain endocytic structures that are remarkably similar to those in animal cells, yet differences at the molecular level, first suggested by analysis of the recently completed (2004) Tetrahymena genome, are turning out to be informative both for mechanistic and evolutionary studies.

Selected Publications

Chilcoat, N.D., Elde, N.C. and Turkewitz, A.P.  An antisense approach to phenotype-based gene cloning in Tetrahymena.  Proc. Natl. Acad. Sci. USA, 98:8709-13, 2001. PubMed Citation

Turkewitz, A.P., Orias, E. and Kapler, G. Functional genomics: the coming of age for Tetrahymena thermophila.  Trends Genet., 18:35-40, 2002. PubMed Citation

Bradshaw, N.R., Chilcoat, N.D., Verbsky, J.W. and Turkewitz, A.P. Proprotein processing within secretory dense core granules of Tetrahymena thermophila.  J. Biol. Chem., 278:4087-95, 2003. PubMed Citation

A.P. Turkewitz. Out with a bang! Tetrahymena as a model system to study secretory granule biogenesis. Traffic, Feb;5(2):63-8, 2004. Review. PubMed Citation

Bowman, G.R., Smith, D.G., Michael Siu, K.W., Pearlman, R.E. and Turkewitz, A.P. Genomic and Proteomic Evidence for a Second Family of Dense Core Granule Cargo Proteins in Tetrahymena thermophila. J Eukaryot Microbiol., Jul-Aug;52(4):291-7, 2005.

Bowman, G.R., Elde, N.C., Morgan, G., Winey, M. and Turkewitz, A.P. Core formation and the acquisition of fusion competence are linked during secretory granule maturation in Tetrahymena. Traffic, Apr;6(4):303-23, 2005.  PubMed Citation

Cowan, A.T., Bowman, G.R., Edwards, K.F., Emerson, J.J., Turkewitz, A.P. Genetic, Genomic, and Functional Analysis of the Granule Lattice Proteins in Tetrahymena Secretory Granules. Mol Biol Cell., Sep;16(9):4046-60, 2005.  PubMed Citation

Elde, N.C., Morgan, G., Winey, M., Sperling, L., Turkewitz, A.P. Elucidation of Clathrin-Mediated Endocytosis in Tetrahymena Reveals an Evolutionarily Convergent Recruitment of Dynamin. PLoS Genet., 1(5) e52, 2005.

Elde, N.C., Long, M. and Turkewitz, A.P. A role for convergent evolution in the secretory life of cells. Trends Cell Biol., 17:157-64, 2007.

Updated 9/4/07.