STUDIES WITH PURPLE ADENINE MUTANTS IN NEUROSPORA CRASSA. IV. LACK OF COMPLEMENTATION BETWEEN DIFFERENT ad-3A MUTANTS IN HETEROKARYONS AND PSEUDOWILD TYPES

Journal Article · Sun May 01 04:00:00 EDT 1960 · Genetics (U.S.)

OSTI ID:4142064

de Serres, F J

Heterokaryon tests on a series of 13 genetically unmarked ad-3A strains of independent origin showed no evidence for interallelic complementation in any pairwise combination. The possibility that such negative results might be inconclusive was investigated with forced heterokaryon tests on genetically marked strnins. No evidence for interallelic complementation in any pairwise combination of these mutants was found in forced heterokaryons grown on unsupplemented medium or medium supplemented with suboptimal levels of adenine. The recovery of true wild type progeny from crosses of different ad-3A mutants with a marked strain of mutant A2 suggest that the ad-3A region consists of an undetermined number of mutable sites, but the lack of asymmetry in marker segregation among the adenine-independent progeny did not permit an ordering of the mutamts with reference to mutant A2 and the adjacent markers hist-2 and nic-2. The failure to recover pseudowild type progeny involving both ad-3A parental chromosomes from the fertile intercrosses provides further evidence for the absence of interallelic complementation in these combinations. The present experiments firmly substantiate the original interpretation of the negative heterokaryon tests with genetically unthe adjacent markers hist-2 and nic-2. The failure to recover pseudowild type progeny involving both ad-3A parental chromosomes from the fertile intercrosses provides further evidence for the absence of interallelic complementation in these combinations. The present experiments firmly substantiate the original interpretation of the negative heterokaryon tests with genetically unmarked but isogenic ad-3 mutants: that, under the experimental conditions used, such results are significant and provide evidence for the absence of complementation. The present data are consistent with the ad-3A locus being a one-cistron locus with an undetermined number of recombinable, mutable sites. (auth)

• Research Organization: Oak Ridge National Lab., Tenn.
• NSA Number: NSA-14-018744
• OSTI ID: 4142064
• Journal Information: Genetics (U.S.), Journal Name: Genetics (U.S.) Vol. Vol: 45; ISSN GENTA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BIOLOGY AND MEDICINE
CHROMOSOMES
FUNGI
GENETICS
MUTATIONS
TESTING