Selection on Viability of Individuals Heterozygous for the Temperature-Sensitive Lethal Mutation l(2)M167DTS in Experimental Populations of Drosophila melanogaster

In experiments on introduction of mutation l(2)M167 ^DTS in Drosophila melanogaster populations, larval and pupal viability and developmental rate are limiting factors determining the intensity of selection on the l(2)M167 ^DTS mutation. Notwithstanding the rapid elimination of the mutation from the population, positive selection for viability was shown, which increased fitness of the mutation carriers in generations. The fitness component viability was estimated in individuals l(2)M167 ^DTS /+; relative to that of wild-type individuals, it varied from 0.5 to 1.0. Factors affecting this trait in overcrowded populations were found.__________Translated from Genetika, Vol. 41, No. 6, 2005, pp. 759–766.Original Russian Text Copyright © 2005 by Kulikov, Marec, Mitrofanov.     

Determination of Fitness Components of Flies Bearing the Recessive Lethal l(2)M167DTS Mutation with Dominant Heat Sensitivity in Artificial Drosophila melanogaster Populations

Elimination of the heat-sensitive l(2)M167 ^DTS mutation from artificial Drosophila melanogaster populations at constant temperature 25°C and various frequencies of the mutation in the parental generation was studied. Components of fitness of the l(2)M167 ^DTS mutation were estimated in the artificial populations by means of the recurrent model of the dependence of the frequency of this mutation in a given generation on its frequency in the previous generation. The model was solved by a numerical method with limitations on the values of some fitness components obtained in test experiments. According to the limitations and frequencies of the l(2)M167 ^DTS mutation, the leading role and limits of the variation in egg-to-adult viability and female fertility were determined. The previously suggested effect of the positive selection for viability of individuals heterozygous for l(2)M167 ^DTS was confirmed.__________Translated from Genetika, Vol. 41, No. 6, 2005, pp. 767–777.Original Russian Text Copyright © 2005 by Kulikov, Kuznetsov, Marec, Mitrofanov.     

The effect of population density on the elimination dynamics of a recessive lethal mutation l(2)M167DTS from experimental populations of Drosophila melanogaster

Dynamics of the elimination of the temperature-sensitive lethal mutation l(2)M167 ^DTS from experimental populations of Drosophila melanogaster under permissive conditions (25°C) was studied. We have shown a rapid elimination of the mutation from the populations, selection for fitness of heterozygous individuals, association of the selection with high larval density and with the direction of the cross that had produced the founder males of the l(2)M167 ^DTS /+ population, and the effect of relative competitive ability of l(2)M167 ^DTS /+ males on the efficiency of the mutation introduction. Modification systems were shown be involved in fitness selection under conditions of high larval density.Translated from Genetika, Vol. 41, No. 3, 2005, pp. 326–333.Original Russian Text Copyright © 2005 by Kulikov, Marec, Mitrofanov.