Date of Completion

Spring 5-6-2012

Thesis Advisor(s)

David Knecht

Disciplines

Biology | Cell and Developmental Biology

Abstract

Actin binding proteins (ABPs) play key roles in the dynamic organization of the actin cytoskeleton during cell movement. The general localization of ABPs during dynamic cellular processes has been characterized. However, their specific functions and mechanisms of regulating the cytoskeleton during motile cellular processes remain unclear. Two approaches have been utilized to ask how these proteins contribute to cytoskeletal function during motility. Using homologous recombination, mutant cell lines lacking α-actinin, fimbrin or both proteins have been created. By analyzing mutants that lack these proteins, we hope to disrupt processes that require a functional cytoskeleton such as phagocytosis, random motility, development, and chemotaxis. Dictyostelium cells lacking a combination of actin binding proteins, including fimbrin, α-actinin, and ABP-34, show reduced cell motility and defects in development. In addition, we have asked whether the presence of a particular ABP in excess influences random motility and chemotaxis. Dictyostelium cell lines over-expressing GFP-Enlazin and 34-GFP show reduced motility.