Entangled and non-modular enhancer sequences producing independent spatial activities.

The modularity of transcriptional enhancers is central to our understanding of morphological evolution, allowing specific changes to a gene expression pattern component, without affecting others. Enhancer modularity refers to physically separated stretches of regulatory sequence producing discrete spatiotemporal transcriptional activity. This concept stems from assays that test the sufficiency of a DNA segment to drive spatial reporter expression resembling that of the corresponding gene.

Regulatory evolution tuning pigmentation intensity quantitatively in .

Quantitative variation in attributes such as color, texture, or stiffness dominates morphological diversification. It results from combinations of alleles at many Mendelian loci. Here, we identify an additional source of quantitative variation among species, continuous evolution in a gene regulatory region.

On the taxonomic status of the tenebrionoid genera Falsopedilus Pic, 1924 and Hintonosia Báguena Corella, 1948 (Coleoptera: Mycteridae) with descriptions of new species.

We re-evaluate the taxonomic placement of the genus Hintonosia Báguena Corella, 1948, hitherto placed in Aderidae Csíki, 1909. The assessment of key morphological characters based on the type specimen of the type species of this genus, Hintonosia bismacrocephalus Báguena Corella, 1948 (= Hintonosia macrocephalus Pic, 1935, homonym), demonstrated that it does not possess the synapomorphies of the Aderidae. Instead, its clear position in Mycteridae Blanchard, 1845 is uncovered, leading us to the transfer of Hintonosia to the subfamily Eurypinae Thomson, 1860 of Mycteridae.

Odor-regulated oviposition behavior in an ecological specialist.

Colonization of a novel ecological niche can require, or be driven by, evolution of an animal's behaviors promoting their reproductive success. We investigated the evolution and sensory basis of oviposition in Drosophila sechellia, a close relative of Drosophila melanogaster that exhibits extreme specialism for Morinda citrifolia noni fruit. D.

Increased chromatin accessibility promotes the evolution of a transcriptional silencer in .

The loss of discrete morphological traits, the most common evolutionary transition, is typically driven by changes in developmental gene expression. Mutations accumulating in regulatory elements of these genes can disrupt DNA binding sites for transcription factors patterning their spatial expression, or delete entire enhancers. Regulatory elements, however, may be silenced through changes in chromatin accessibility or the emergence of repressive elements.

The genus Syzeton Blackburn, 1891 (Coleoptera, Aderidae) in the United States of America.

The species of Syzeton Blackburn, 1891 (=Zonantes Casey, 1895, syn. nov.) known from the United States are revised.

A standardized nomenclature and atlas of the female terminalia of .

The model organism has become a focal system for investigations of rapidly evolving genital morphology as well as the development and functions of insect reproductive structures. To follow up on a previous paper outlining unifying terminology for the structures of the male terminalia in this species, we offer here a detailed description of the female terminalia of . Informative diagrams and micrographs are presented to provide a comprehensive overview of the external and internal reproductive structures of females.

Large-scale analysis of Drosophila core promoter function using synthetic promoters.

The core promoter plays a central role in setting metazoan gene expression levels, but how exactly it "computes" expression remains poorly understood. To dissect its function, we carried out a comprehensive structure-function analysis in Drosophila. First, we performed a genome-wide bioinformatic analysis, providing an improved picture of the sequence motifs architecture.

Resolving between novelty and homology in the rapidly evolving phallus of Drosophila.

The genitalia present some of the most rapidly evolving anatomical structures in the animal kingdom, possessing a variety of parts that can distinguish recently diverged species. In the Drosophila melanogaster group, the phallus is adorned with several processes, pointed outgrowths, that are similar in size and shape between species. However, the complex three-dimensional nature of the phallus can obscure the exact connection points of each process.

New Mixaderus species from the Mascarene Islands (Coleoptera: Aderidae).

Following a previous revision of species of the genus Mixaderus Collado Alonso-Zarazaga, 1996 (Coleoptera: Aderidae) from Madagascar and the Mascarene islands, I describe here six new species from the same genus from La Réunion and Mauritius: Mixaderus reunionensis n. sp.; Mixaderus chassaini n.

Review of Aderidae Csiki, 1909 (Insecta: Coleoptera) of Cabo Verde.

The Aderidae (Coleoptera: Tenebrionoidea) of Cabo Verde (or Cape Verde in English transcription) Archipelago in the Central Atlantic Ocean is revised based on an examination of types and additional material. Four species are confirmed for the archipelago, three of the genus Cobososia Collado et Alonso-Zarazaga, 1996 and one of the genus Aderus Stephens, 1829. We also propose to transfer Anthicus reductus Wollaston, 1867 (Anthicidae: Anthicinae: Anthicini) to the genus Cobososia (Aderidae), as Cobososia reducta (Wollaston, 1867) comb.

Regulatory encoding of quantitative variation in spatial activity of a enhancer.

Developmental enhancers control the expression of genes prefiguring morphological patterns. The activity of an enhancer varies among cells of a tissue, but collectively, expression levels in individual cells constitute a spatial pattern of gene expression. How the spatial and quantitative regulatory information is encoded in an enhancer sequence is elusive.

A sensitive mNeonGreen reporter system to measure transcriptional dynamics in Drosophila development.

The gene regulatory network governing anterior-posterior axis formation in Drosophila is a well-established paradigm to study transcription in developmental biology. The rapid temporal dynamics of gene expression during early stages of development, however, are difficult to track with standard techniques. We optimized the bright and fast-maturing fluorescent protein mNeonGreen as a real-time, quantitative reporter of enhancer expression.

Synopsis of the Asian species in the genus Zarcosia Collado amp; Alonso-Zarazaga, 1996 with new combinations and descriptions of fourteen new species.

This work represents a provisional inventory of Asian species placed in the genus Zarcosia Collado Alonso-Zarazaga, 1996. Most of these species had not been reassigned since their original description under now obsolete genera, in spite of the morphological homogeneity of the genus Zarcosia Collado Alonso-Zarazaga, 1996. The present work includes the following transfers resulting in 34 new combinations: Z.

Enhancer evolutionary co-option through shared chromatin accessibility input.

The diversity of forms in multicellular organisms originates largely from the spatial redeployment of developmental genes [S. B. Carroll, 134, 25-36 (2008)].

Near-chromosome level genome assembly of the fruit pest Drosophila suzukii using long-read sequencing.

Over the past decade, the spotted wing Drosophila, Drosophila suzukii, has invaded Europe and America and has become a major agricultural pest in these areas, thereby prompting intense research activities to better understand its biology. Two draft genome assemblies already exist for this species but contain pervasive assembly errors and are highly fragmented, which limits their values. Our purpose here was to improve the assembly of the D.

A strawberry accession with elevated methyl anthranilate fruit concentration is naturally resistant to the pest fly Drosophila suzukii.

During the past decade, Drosophila suzukii has established itself as a global invasive fruit pest, enabled by its ability to lay eggs into fresh, ripening fruit. In a previous study, we investigated the impact of different strawberry accessions on the development of D. suzukii eggs, in the search of natural resistance.

Developmental Transcriptional Enhancers: A Subtle Interplay between Accessibility and Activity: Considering Quantitative Accessibility Changes between Different Regulatory States of an Enhancer Deconvolutes the Complex Relationship between Accessibility and Activity.

Measurements of open chromatin in specific cell types are widely used to infer the spatiotemporal activity of transcriptional enhancers. How reliable are these predictions? In this review, it is argued that the relationship between the accessibility and activity of an enhancer is insufficiently described by simply considering open versus closed chromatin, or active versus inactive enhancers. Instead, recent studies focusing on the quantitative nature of accessibility signal reveal subtle differences between active enhancers and their different inactive counterparts: the closed silenced state and the accessible primed and repressed states.

Evolution: Remodelling Animal Body Plans, Gene by Gene.

Changes in Homeotic (Hox) gene regulation have long been thought to drive the evolution of animal body plans. Direct genetic evidence of their evolutionary role has, however, remained limited. A new study reveals how several mutations distributed across a gene network mask the phenotypic effects of a Hox gene's evolution.

Quantitative and Discrete Evolutionary Changes in the Egg-Laying Behavior of Single Females.

How a nervous system assembles and coordinates a suite of elementary behavioral steps into a complex behavior is not well understood. While often presented as a stereotyped sequence of events, even extensively studied behaviors such as fly courtship are rarely a strict repetition of the same steps in a predetermined sequence in time. We are focusing on oviposition, the act of laying an egg, in flies of the genus to describe the elementary behavioral steps or microbehaviors that a single female fly undertakes prior to and during egg laying.

Evolution of Ovipositor Length in Drosophila suzukii Is Driven by Enhanced Cell Size Expansion and Anisotropic Tissue Reorganization.

Morphological diversity is dominated by variation in body proportion [1], which can be described with scaling relationships and mathematical equations, following the pioneering work of D'Arcy Thompson [2] and Julian Huxley [3]. Yet, the cellular processes underlying divergence in size and shape of morphological traits between species remain largely unknown [4-8]. Here, we compare the ovipositors of two related species, Drosophila melanogaster and D.

A short guide to insect oviposition: when, where and how to lay an egg.

Egg-laying behavior is one of the most important aspects of female behavior, and has a profound impact on the fitness of a species. As such, it is controlled by several layers of regulation. Here, we review recent advances in our understanding of insect neural circuits that control when, where and how to lay an egg.

ATAC-seq reveals regional differences in enhancer accessibility during the establishment of spatial coordinates in the blastoderm.

Establishment of spatial coordinates during embryogenesis relies on differential regulatory activity of axis patterning enhancers. Concentration gradients of activator and repressor transcription factors (TFs) provide positional information to each enhancer, which in turn promotes transcription of a target gene in a specific spatial pattern. However, the interplay between an enhancer regulatory activity and its accessibility as determined by local chromatin organization is not well understood.

Drosophila (Sophophora) carrolli n. sp., a new species from Brunei, closely related to Drosophila (Sophophora) rhopaloa Bock Wheeler, 1972 (Diptera: Drosophilidae).

We describe a new species in the Drosophila melanogaster species group, Drosophila carrolli n. sp., showing morphological affinities with D.