Descriptions of recently evolved genes suggest several mechanisms origin including exon shuffling, gene fission/fusion, retrotransposition, duplication-divergence, and lateral transfer, all which involve recruitment preexisting or genetic elements into new function. The importance noncoding DNA in the novel remains an open question. We used well annotated genome model system Drosophila melanogaster sequences related species to carry out a whole-genome search for D. that are derived from DNA....

Abstract Drosophila melanogaster shows clinal variation along latitudinal transects on multiple continents for several phenotypes, allozyme variants, sequence and chromosome inversions. Previous investigation suggests that many such clines are due to spatially varying selection rather than demographic history, but the genomic extent of is unknown. To map differentiation throughout genome, we hybridized DNA from temperate subtropical populations Affymetrix tiling arrays. The dense sampling...

Telomere length is inherited directly as a DNA sequence and classic quantitative trait controlled by many genes across the genome. Here, we show that neither paradigm fully accounts for telomere inheritance, which also depends on parent-of-origin effect elongation in early embryo. By reciprocally crossing mouse strains with different lengths, find telomeres elongate hybrid embryos only when maternal are short paternal long. In reciprocal cross, shorten. These differences embryonic...

The genotypic signature of spatially varying selection is ubiquitous across the Drosophila melanogaster genome. Spatially structured adaptive phenotypic differences are also commonly found, particularly along New World and Australian latitudinal gradients. However, investigation gene expression variation in one or multiple environments these well-studied populations surprisingly limited. Here, we report genome-wide transcript levels tropical temperate eastern reared at two temperatures. As...

Heterochromatin is the gene-poor, satellite-rich eukaryotic genome compartment that supports many essential cellular processes. The functional diversity of proteins bind and often epigenetically define heterochromatic DNA sequence reflects diverse functions supported by this enigmatic compartment. Moreover, heterogeneous signatures selection at chromosomal mirror heterogeneity evolutionary forces act on DNA. To identify new such surrogates for dissecting heterochromatin function evolution,...

In most eukaryotes, telomerase counteracts chromosome erosion by adding repetitive sequence to terminal ends. Drosophila melanogaster instead relies on specialized retrotransposons that insert exclusively at telomeres. This exchange of goods between host and mobile element-wherein the element provides an essential genome service a hospitable niche for propagation-has been called "genomic symbiosis." However, these telomere-specialized, jockey family may actually evolve "selfishly"...

Fluctuating environments threaten fertility and viability. To better match the immediate, local environment, many organisms adopt alternative phenotypic states, a phenomenon called “phenotypic plasticity.” Natural populations that predictably encounter fluctuating tend to be more plastic than conspecific constant suggesting plasticity can adaptive. Despite pervasive evidence of such “adaptive plasticity,” gene regulatory mechanisms underlying remains poorly understood. Here we test...

Telomeres are nucleoprotein complexes at the ends of linear chromosomes. These specialized structures ensure genome integrity and faithful chromosome inheritance. Recurrent addition repetitive, telomere-specific DNA elements to combats end-attrition, while telomere-associated proteins protect naked, double-stranded from promiscuous repair into end-to-end fusions. Although telomere length homeostasis end-protection ubiquitous across eukaryotes, there is sporadic but building evidence that...

Abstract Maintaining genome integrity is vital for organismal survival and reproduction. Essential, broadly conserved DNA repair pathways actively preserve integrity. However, many proteins evolve adaptively. Ecological forces like UV exposure are classically cited drivers of evolution. Intrinsic repetitive DNA, which also imperil integrity, have received less attention. We recently reported that a Drosophila melanogaster-specific satellite array triggered species-specific, adaptive...

Abstract A species tree is a central concept in evolutionary biology whereby single branching phylogeny reflects relationships among species. However, the phylogenies of different genomic regions often differ from tree. Although discordance widespread phylogenomic studies, we still lack clear understanding how variation phylogenetic patterns shaped by genome or extent to which may compromise comparative studies. We characterized across murine rodents – large and ecologically diverse group...

Abstract Despite being essential for fertility, genome-defense-pathway genes often evolve rapidly. However, little is known about the molecular basis of this adaptation. Here, we characterized evolution a protein interaction network within PIWI-interacting small RNA (piRNA) genome-defense pathway in Drosophila at unprecedented scale and evolutionary resolution. We uncovered pervasive rapid anchored heterochromatin 1 (HP1) paralog Rhino. Through cross-species high-throughput yeast-two-hybrid...

Compensation following herbivory is an important element of plant defense; however, variation in compensation under naturally stressful conditions has yet to be evaluated directly. During Arizona's worst drought on record, we explored ungulate a typically overcompensating population scarlet gilia (Ipomopsis aggregata) near Flagstaff, Arizona, USA. In natural survey browsed and unbrowsed plants, documented severe undercompensation. We tested two factors that potentially contributed this...

Transposable elements (TEs) comprise large fractions of many eukaryotic genomes and imperil host genome integrity. The combats these challenges by encoding proteins that silence TE activity. Both the introduction new TEs via horizontal transfer sequence evolution requires constant innovation host-encoded silencing machinery to keep pace with TEs. One form is adaptation existing, single-copy genes. Indeed, suppressors replication often harbor signatures positive selection. Such are especially...

Sperm-packaged DNA must undergo extensive reorganization to ensure its timely participation in embryonic mitosis. Whereas maternal control over this remodeling is well described, paternal contributions are virtually unknown. In study, we show that Drosophila melanogaster males lacking Heterochromatin Protein 1E (HP1E) sire inviable embryos catastrophic these embryos, the genome fails condense and resolve into sister chromatids synchrony with genome. This delay leads a failure of chromosomes,...

Essential, conserved cellular processes depend not only on essential, strictly proteins but also essential that evolve rapidly. To probe this poorly understood paradox, we exploited the rapidly evolving Drosophila telomere-binding protein, cav /HOAP, which protects chromosomes from lethal end-to-end fusions. We replaced D. melanogaster HOAP with a highly diverged version its close relative, yakuba . The D ('HOAP[yak]') localizes to telomeres and However, HOAP[yak] fails rescue previously...

Abstract The packaging of DNA into proper chromatin structure contributes to transcriptional regulation. This is environment sensitive, yet its role in adaptation novel environmental conditions completely unknown. We set out identify candidate chromatin-remodeling loci that are differentiated between tropical and temperate populations Drosophila melanogaster, an ancestrally equatorial African species has recently colonized environments around the world. Here we describe sequence variation at...