Projects We’re Currently Working On:

Climatic adaptations have been thought to play an important reason of chromosomal inversions. In D. melanogaster, for example, some inversions show seasonal and latitudinal variations. Because many fitness traits show congruent variation pattern with these chromosomal inversions, it is plausible to hypothesize that inversion underlies observed seasonal/ latitudinal patterns for some of these traits.

There are recent papers, which show evidence of the role of chromosomal inversions in relation to biological processes such as local adaptations and speciation. The classical example of the adaptive role of chromosomal polymorphism is the clines of inversion frequencies repeatable across the continents. However, there is limited knowledge about the molecular variation associated with these polymorphisms, which makes this project valuable. We aim to identify environmental variables that effect on the frequency of occurrence of chromosomal inversions.

We only focus on seasonal variation of phenotypic effects on D. melanogaster. From this reasons we use population collected from the same geographical region in different time points. In this viewpoint, tolerance of lineages against hot and cold, starvation and desiccation, and reproductive (ovarian) diapause and lipid content will be evaluated. After we decide the phenotypes that show seasonal variation, cytological assessment will be evaluated on chromosomal inversions. In the last step of this project, we will use next-generation sequencing to have full genome data of each lineage. Then, the frequency of common inversions and single nucleotide polymorphisms will be analyzed. All data will be analyzed using a generalized linear models to show the relationship between seasonal phenotypes and chromosomal inversions.

In case of determination of adaptive changes related with the climate in chromosomal inversions, we will evaluate these results taking in account the other similar studies. Genetic indicators, which found in D.melanogaster populations, may be considering as climate change indicators as well.

Analysis of the genetic variability in natural populations is an important tool in the field of population, evolutionary, and ecologic genetics, together with Drosophila as a model for these studies. In recent years, a bulk of information about DNA sequences of functionally important genes and whole individual genomes from natural populations was collected. Several directions are of a particular importance for further research in this field. Analysis of genomes in populations inhabiting different environments can provide unique insights into forces shaping genomic polymorphism and divergence. Temporal changes in variation patterns within the same population are still to be studied. Understanding the functional value of the genome variation existing in nature might shed light on mechanisms involved in maintaining genetic variation and regulation of gene expression.

The long term goal of this project is to assess latitudinal, seasonal, and year-to-year variation in genome, transcriptome, and life history traits in Drosophila melanogaster populations.