AN APPARENT CONNECTION BETWEEN HISTIDINE, RECOMBINATION, AND REPAIR IN NEUROSPORA

Dorothy Newmeyer ¹, Alice L. Schroeder ², and Donna R. Galeazzi ¹

¹ Department of Biological Sciences, Stanford University, Stanford, California 94305
² Program in Genetics, Washington State University, Pullman, Washington 99163

Two mutants of Neurospora crassa, uvs-3 and mei-3 , share four properties—UV sensitivity, inhibition by histidine, meiotic blockage when homozygous, and increased duplication instability (due to mitotic crossing over, to deletions or to both). The present paper shows that a third nonallelic mutant, uvs-6, exhibits the same four properties.—Also, the instability of duplications in the absence of any UV-sensitive mutant is increased by the presence of histidine in the growth medium.