Multiple loci linked to inversions are associated with eye size variation in species of the Drosophila virilis phylad.

The size and shape of organs is tightly controlled to achieve optimal function. Natural morphological variations often represent functional adaptations to an ever-changing environment. For instance, variation in head morphology is pervasive in insects and the underlying molecular basis is starting to be revealed in the Drosophila genus for species of the melanogaster group.

Cloudy with a Chance of Insights: Context Dependent Gene Regulation and Implications for Evolutionary Studies.

Research in various fields of evolutionary biology has shown that divergence in gene expression is a key driver for phenotypic evolution. An exceptional contribution of -regulatory divergence has been found to contribute to morphological diversification. In the light of these findings, the analysis of genome-wide expression data has become one of the central tools to link genotype and phenotype information on a more mechanistic level.

Origin and Consequences of Chromosomal Inversions in the virilis Group of Drosophila.

In Drosophila, large variations in rearrangement rate have been reported among different lineages and among Muller's elements. Nevertheless, the mechanisms that are involved in the generation of inversions, their increase in frequency, as well as their impact on the genome are not completely understood. This is in part due to the lack of comparative studies on species distantly related to Drosophila melanogaster.

The Drosophila melanogaster Muc68E Mucin Gene Influences Adult Size, Starvation Tolerance, and Cold Recovery.

Mucins have been implicated in many different biological processes, such as protection from mechanical damage, microorganisms, and toxic molecules, as well as providing a luminal scaffold during development. Nevertheless, it is conceivable that mucins have the potential to modulate food absorption as well, and thus contribute to the definition of several important phenotypic traits. Here we show that the Drosophila melanogaster Muc68E gene is 40- to 60-million-yr old, and is present in Drosophila species of the subgenus Sophophora only.

Drosophila americana Diapausing Females Show Features Typical of Young Flies.

Diapause is a period of arrested development which is controlled physiologically, preprogrammed environmentally and characterized by metabolic depression that can occur during any stage of insect development. Nevertheless, in the genus Drosophila, diapause is almost always associated with the cessation of ovarian development and reproductive activity in adult females. In this work, we show that, in D.

Genes belonging to the insulin and ecdysone signaling pathways can contribute to developmental time, lifespan and abdominal size variation in Drosophila americana.

Even within a single genus, such as Drosophila, cases of lineage-specific adaptive evolution have been found. Therefore, the molecular basis of phenotypic variation must be addressed in more than one species group, in order to infer general patterns. In this work, we used D.

The Drosophila melanogaster methuselah gene: a novel gene with ancient functions.

The Drosophila melanogaster G protein-coupled receptor gene, methuselah (mth), has been described as a novel gene that is less than 10 million years old. Nevertheless, it shows a highly specific expression pattern in embryos, larvae, and adults, and has been implicated in larval development, stress resistance, and in the setting of adult lifespan, among others. Although mth belongs to a gene subfamily with 16 members in D.

Drosophila americana as a model species for comparative studies on the molecular basis of phenotypic variation.

Understanding the molecular basis of within and between species phenotypic variation is one of the main goals of Biology. In Drosophila, most of the work regarding this issue has been performed in D. melanogaster, but other distantly related species must also be studied to verify the generality of the findings obtained for this species.

A comparative study of the short term cold resistance response in distantly related Drosophila species: the role of regucalcin and frost.

The molecular basis of short term cold resistance (indexed as chill-coma recovery time) has been mostly addressed in D. melanogaster, where candidate genes (Dca (also known as smp-30) and Frost (Fst)) have been identified. Nevertheless, in Drosophila, the ability to tolerate short term exposure to low temperatures evolved several times independently.

Resolving the phylogenetic relationships and evolutionary history of the Drosophila virilis group using multilocus data.

The Drosophila virilis group is one of the major lineages of Drosophila previously recognised and it has been used as a model for different types of studies. It comprises 13 species whose phylogenetic relationships are not well resolved. In the present study, six nuclear genes (Adh, fused, Gpdh, NonA, CG9631 and CG7219) and the mitochondrial ribosomal RNA genes (12S-16S) have been used to estimate the evolutionary tree of the group using different methods of phylogenetic reconstruction.

Drosophila genes that affect meiosis duration are among the meiosis related genes that are more often found duplicated.

Using a phylogenetic approach, the examination of 33 meiosis/meiosis-related genes in 12 Drosophila species, revealed nine independent gene duplications, involving the genes cav, mre11, meiS332, polo and mtrm. Evidence is provided that at least eight out of the nine gene duplicates are functional. Therefore, the rate at which Drosophila meiosis/meiosis-related genes are duplicated and retained is estimated to be 0.

An old bilbo-like non-LTR retroelement insertion provides insight into the relationship of species of the virilis group.

In Drosophila, at the population and species level, fixation of a TE insertion is an unlikely fate. Of the few reported fixations at the species level most involve non-LTR retroelements. In this work we report the fixation of a non-LTR retroelement in five species (Drosophila littoralis, Drosophila virilis, Drosophila lummei, Drosophila americana and Drosophila novamexicana) of the virilis group of Drosophila.