Chapter 18 Methods for Isolating and Analyzing Mitotic Mutants in Aspergillus nidulans

Abstract

Publisher Summary This chapter overviews the process of isolating and studying mitotic mutants in Aspergillus nidulans. The three approaches used to isolate mitotic mutants in A. nidulans are: (i) the isolation of randomly mutagenized temperature-sensitive mutants, which are subsequently screened microscopically for mitotic blockage, (ii) the isolation of tubulin mutations that block microtubule function and mitosis by isolating antimicrotubule drug-resistant mutants and screening for temperature sensitivity, and (iii) the isolation of conditionally lethal revertants of existing mitotic or tubulin mutants. In addition, mutant alleles of cloned genes that are essential for mitosis can be created at will in A. nidulans . To understand how mutations are generated and studied in A. nidulans, it is important to understand the life cycle and cell cycle of this organism. A. nidulans can reproduce both asexually (vegetatively) and sexually. Vegetative reproduction occurs through asexual spores called conidospores or conidia. Conidia are quite small (3–3.5 pm) in size and each contains a single nucleus. The cell cycle of A. nidulans is similar to that of higher organisms.