Gregory M. Guild, Ph.D.

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Graduate Group Affiliations

Contact information
319 Leidy Labs
Philadelphia, PA 19104
Office: 215 898-3433
Fax: 215 898-8780
B.A. (Biological Sciences)
North Carolina State University, 1972.
Ph.D. (Microbiology)
Rutgers University, 1976.
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Description of Research Expertise

Research Interests
Eukaryotic cell shape

Key words: Drosophila, cytoskeleton, actin filaments, actin binding proteins, cell shape.

Description of Research
How do eukaryotic cells morph into and maintain a myriad of different cell shapes? In many cases, crossbridged bundles of polarized actin filaments provide the cytoskeletal scaffolding for this. We are interested in discovering the critical components required for filament bundling and the assembly principles cells use to generate shape. We use Drosophila as a model system because we can employ molecular and genetic tools to modify cytoskeleton assembly and confocal and electron microscopic techniques to evaluate the cell biological consequences in real time or at high resolution. In order to permit detection of cell shape changes with high sensitivity, we study cells that have an extreme shape – primarily the bristle cells that cover the fly. These are single cells that grow to elongate a beautiful curved extension that is 400 µm in length. We are interested in two specific questions. How are extremely long actin bundles constructed and what role does filament dynamics play in this process. Since all eukaryotes use actin cytoskeletons to establish shape, what we learn from flies is likely to be widely applicable.

Lab personnel:
Megan Malloy – Research Specialist
Felina Zolotarev – Undergraduate Student
Bo Zhou – Undergraduate Student
Tim Wilkins – Undergraduate Student
Roslyn Duvall – Undergraduate Student

Selected Publications

Guild, G.M., P.S. Connelly, L. Ruggiero, K.A. Vranich and L.G. Tilney : Actin filament bundles in Drosophila wing hairs: Hairs and bristles use different strategies for assembly. Mol. Biol. Cell 16: 3620-3631, 2005.

Tilney LG, Connelly PS, Guild GM, Vranich KA, Artis D. : Adaptation of a nematode parasite to living within the mammalian epithelium. J Exp Zoolog A Comp Exp Biol 303: 927-45. 2005.

Tilney, L.G., P.S. Connelly, and G.M. Guild: Microvilli appear to represent the first step in actin bundle formation in Drosophila bristles. J. Cell Sci. 117: 3531-3538, 2004.

Tilney, L.G., P.S. Connelly, L. Ruggiero, K.A. Vranich, L. Ruggiero, Guild, G.M. and DeRosier, D. : The role actin filaments play in providing the characteristic curved form of Drosophila bristles. Mol. Biol. Cell 15: 5481-91, 2004.

Tilney, L.G., P.S. Connelly, L. Ruggiero, K.A. Vranich, L. Ruggiero, and Guild, G.M. : Actin filament turnover regulated by cross-linking accounts for the size, shape, location and number of actin bundles in Drosophila bristles. Mol. Biol. Cell 14: 3953-66, 2003.

Guild, G.M., P.S. Connelly, L. Ruggiero, K.A. Vranich, and L.G. Tilney: Long continuous actin bundles in Drosophila bristles are constructed by overlapping short filaments. J. Cell Biol 162: 1069-77, 2003.

Guild, G.M., P.S. Connelly, K.A. Vranich, M.K. Shaw and L.G. Tilney: Actin filament turnover removes bundles from Drosophila bristle cells. J. Cell Sci. 115: 641-53, 2002.

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Last updated: 08/21/2009
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