Wild-type and mutant stocks of Aspergillus nidulans.

VER the past decade the homothallic ascomycete Aspergillus nidulans has become an important organism for genetic investigation. As a consequence of the pioneering research of PROFESSOR G. PONTECORVO and associates, a wide variety of mutant strains have become available for research and teaching. Recognizing these facts, the Committee on the Maintenance of Genetic Stocks of the Genetics Society of America suggested that stocks of A . nidulans be added to those of Neurospora at the Fungal Genetics Stock Center. Established in 1960 for the maintenance and distribution of fungal genetic strains, the center first concentrated on Neurospora, and currently contains over 1250 mutant and wildtype strains of Neurospora (for stock list see BARRATT and OGATA 1964*). In 1962, Aspergillus workers were requested to deposit significant genetic stocks of A . nidulans with the Fungal Genetics Stock Center. DR. ETTA KAFER, Department of Genetics, McGill University, agreed to act as a consultant. More than 170 strains have now been deposited and are available for free distribution. The lists and descriptions in the present report are intended to serve as a reference for individuals wishing to make use of Aspergillus stocks for research or teaching. Additional information on many of these strains and others may be obtained from Aspergillus Newsletter (DR. J. A. ROPER, Editor, Department of Genetics, The University, Sheffield 10, England). It is hoped that the appearance of this paper will encourage the deposition of additional stocks. The stocks are given in five tables, which include listings of gene loci, mutant strains. wild-type strains, heterocaryon incompatable strains, and a brief classification of the general character and principal usefulness of each strain. Pedigrees of all but a few stocks are given in Figures 1 and 2 of the present paper, and in Figures 2 through 6 of GFER (1965). It has become evident that certain translocations have become widespread among existing Aspergillus stocks. Owing to the work of DR. ETTA KAFER (KAFECR 1965), detailed information is available concerning the presence and nature of translocations in the stocks listed in this paper. References cited on the origin of strains refer to published information in which the year of origin, person who obtained the mutant, etc., can be found, as well as available information on mapping. It should be noted that very often a different person obtained a mutant than the one who published it. For proper credit to the originators of these mutants, refer to the reference cited.