ISSN:
1432-0983
Keywords:
Missense suppressors
;
tRNA suppressors
;
Coprinus
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Recessiveness and dosage effects of two suppressor genes in Coprinus were correlated with suppressed enzyme activity in cell free extracts. Wild type, the suppressible acu-1.4 mutation and suppressor gene mutations supa4.1+ and supa4.2+ were used to construct appropriate diploid strains which allowed comparison of the following situations: (i) wild type, (ii) unsuppressed mutant (iii) homoallelism for a single suppressor, (iv) heterozygosity for a single suppressor (sup +/sup −) and (v)heterozygosity for two nonallelic suppressors. Extracts of the unsuppressed mutant had no enzyme activity whereas extracts of both the homoallelic suppressor strains had the suppressed level of some 20% wild type acetyl-CoA synthetase activity. Diploids heterozygous for sup +/sup − were acu− in phenotype. These had only 3–6% wild type enzyme activity, a level too low to support growth on acetate and hence the apparent recessiveness of each sup + mutation. The doubly heterozygous diploid had exactly the same level of enzyme activity as homoallelic diploids, 20% wild type, hence the acu + suppressed phenotype.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00377605
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