MICROSCOPY Vol.44▶No.3 2009

Ultrastructural Analysis of the Actin Cytoskeleton in Fission Yeast

Tomoko Kamasaki, Tomoko Takagi, Issei Mabuchi and Masako Osumi

Abstract: In eukaryotes, the actin cytoskeleton plays important roles in polarized cell growth and cytokinesis. Fission yeastis a model system for studying formation and role of actin cytoskeleton. Actin cytoskeleton in fission yeast cells forms patch, cable, and ring, which have been mainly observed by fluorescent microscopy. On the other hand, little is known about ultrastructures of actin cytoskeleton. Recently, we visualized the ultrastructure of these F-actin structures by high-pressure freezing and immuno electron microscopy. Furthermore, we clarified the directionality of F-actins forming the actin cytoskeleton in fission yeast cells. These results provide fundamental informations of actin cytoskeleton and insights into elucidating the functions.

Key words: actin cytoskeleton,high-pressure freezing,myosin-S1 decoration,fission yeast,electron microscope