International Review of Cytology presents current advances and comprehensive reviews in cell biology both plant and animal. Authored by some of the foremost scientists in the field, each volume provides up-to-date information and directions for future research. Articles in this volume address biosynthesis and alternate targeting of the lysosomal cysteine protesase cathepsin L, microtubule-associated proteins and their essential roles during mitosis, molecular and functional analysis of the dictyostelium centrosome, polytene chromosomes, and insect basic leucine zipper proteins and their role in cyclic AMP dependent regulation of gene expression.