0000000000661040
AUTHOR
A González
Chromosomal polymorphism and patterns of viability in natural populations of Drosophila melanogaster from cellar and vineyard.
Two neighbouring natural populations of Drosophila melanogaster have been analysed, one from a cellar habitat and the other from a vineyard outside. An extensive study of inversion polymorphism in the two populations has been carried out. Furthermore, the relationship between inversion polymorphism and the viability of the second chromosome has been studied. The data regarding the total frequency of inversion-carrying chromosomes indicate a lower frequency in the cellar population than in the vineyard population. Some possibilities that could explain the behaviour of the chromosomes from the cellar in relation to the peculiar environment of this habitat are discussed. New endemic inversions…
Genetic polymorphism and high detrimental load in natural populations of Drosophila melanogaster from cellar and vineyard
Two Spanish natural populations of Drosophila melanogaster have been analysed with respect to genetic variability in third chromosome viability. The two populations, although from the same locality, belong to relatively different habitats: the inside of a cellar and a vineyard. The patterns of homozygote and heterozygote viability are similar in both populations. The homozygous detrimental loads estimated are very high and the values for the D:L (detrimental/lethal) ratio close to 2.5, which is higher than any previously found. The environmental variance of viability, average degrees of dominance of lethal genes and of viability polygenes and effective population sizes were estimated in eac…
Identification, characterization and analysis of expression of genes encoding arylalkylamine N-acetyltransferases in the pea aphidAcyrthosiphon pisum
Most organisms exhibit some kind of rhythmicity in their behaviour and/or physiology as an adaptation to the cyclical movements of the Earth. In addition to circadian rhythms, many organisms have an annual rhythmicity in certain activities, such as reproduction, migration or induction of diapause. Current knowledge of the molecular basis controlling seasonal rhythmicity, especially in insects, is scarce. One element that seems to play an essential role in the maintenance of both circadian and seasonal rhythms in vertebrates is the hormone melatonin. In vertebrates, the limiting enzyme in its synthesis is the arylalkylamine N-acetyltransferase (AANAT). Melatonin is also present in insects bu…