A REVERSE GENETICS BASED SCREEN FOR ACTIN MUTANTS IN SCHIZOSACCHAROMYCES POMBE

Abstract

Actin is a eukaryotic cytoskeletal protein with multiple cellular functions. The detailed investigation of actin¿s role in a particular process has been hampered by the lack of mutants defective only in that specific actin function. With the primary goal to dissect actin¿s function in cytokinesis, a total of 39 fission yeast actin mutants were identified. The first part of this thesis describes the key findings from this screen. Some mutants were defective in either a discrete actin function or in a particular structure of actin. Described in the second part is the oscillatory pattern of actin patches seen in one mutant. An actin turnover defect in this mutant might generate patterns of alternating assembly and disassembly of actin. Oscillations in many dynamic cellular processes have been shown before and these oscillations may share many common features. Analysis of this actin mutant might help understand the underlying principles behind such oscillatory patterns.