Complementation between mutants of Phycomyces deficient with respect to carotenogenesis

✍ Scribed by Ootaki, T. ;Lighty, Anita Crafts ;Delbrück, M. ;Hsu, Wan-Jean

• Publisher: Springer
• Year: 1973
• Tongue: English
• Weight: 702 KB
• Volume: 121
• Category: Article
• ISSN: 0026-8925
• DOI: 10.1007/bf00353693

✦ Synopsis

White and red mutants of Phycomyces, derived from two independent wild types (yellow) by mutagenesis using nitrosoguanidine, either in a single step (26 whi~, 5 red mutants), or in two steps (10 white mutants, from one of the red mutants) were studied with respect to complementation in heterokaryons. The tests clearly establish the involvement of three and only three genes, here named sarA, carB, and sarR. The sarA and the sarB mutants are white, the sarA mutants do not accumulate phytoene, the sarB mutants do. The carR mutants are red and accumulate lyeopene. The two step mutants are either sara and carR, or sarB and sat/? double mutants. A few of the white mutants obtained in a single mutagenization step are affected in sara and sarR. They may be polar mutants in an operon or accidental double mutants.