[
International Worm Meeting,
2005]
Cellular autophagy is a process for the degradation of cytoplasmic constituents in eukaryotic cells. Since its discovery in 1957 in the epithelial cells of kidney of the newborn mice (1) electron microscopy has been and still remains an indispensable method for studying autophagy. One of the main reasons of the late start of autophagy research in C. elegans is the relative difficulty of performing transmission electron microscopy with worm samples. Recently we have developed a technique by which autophagic processes of the worm become accessible for systematic morphological and, in three major tissue types, for morphometric analysis by transmission electron microscopy (2). Our poster introduces the method, presents the criteria for the identification and morphological analysis of various types of autophagic vacuoles in all major cell types, and shows the latest morphometric data on autophagy in hypodermal, gut epithelial and body wall muscle cells during postembryonic development including all four larval, as well as the predauer, dauer and postdauer stages. Our results indicate that the cells of continuously feeding worms are practically devoid of autophagic vacuoles. Significant increase in the quantity of autophagic vacuoles can be observed at the end of each larval stage when the lethargus is reactivated. Systematic measurements on Daf-c mutants in the predauer period show that preparation for the dauer stage does not involve constitutive autophagic activity. (1) Clark S.L. (1957) Cellular differentiation in the kidneys of newborn mice studied with the electron microscope, J. Biophysic. Biochem. Cytol. 3, 349 (2) Kovacs AL, Vellai T, Muller F (2004) Autophagy in Caenorhabditis elegans. In: "Autophagy" Ed. Daniel J. Klionsky, Landes Bioscience 2004, Chapter 17, pp 216-223