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Genomics Mar 2022The subfamily Ototretinae represents an important and unusual lineage of fireflies. Here, we sequenced and annotated three mitogenomes for this subfamily, with two...
The subfamily Ototretinae represents an important and unusual lineage of fireflies. Here, we sequenced and annotated three mitogenomes for this subfamily, with two Stenocladius species and one Drilaster species as representatives. The mitogenome of Stenocladius exhibits a rearranged gene order between trnC and trnW caused by transposition, which is a novel finding in Lampyridae. Meanwhile, a long intergenic space (241 to 376 bp) exists between the two rearranged genes, and some remnants (23 bp) of trnW are present within this non-coding region. Moreover, phylogenetic analyses did not recover the monophyly of Ototretinae, in which Drilaster is shown at a basal lineage in Lampyridae, but Stenocladius seems more related to Luciolinae. Therefore, the gene rearrangement in Stenocladius is presumed to result from independent evolutionary events, suggesting that this genus should be placed in a separate lineage. Nevertheless, more representative mitogenomes from different groups are required to verify the present results.
Topics: Animals; Coleoptera; Fireflies; Gene Rearrangement; Genome, Mitochondrial; Phylogeny
PubMed: 35131472
DOI: 10.1016/j.ygeno.2022.110305 -
Journal of Evolutionary Biology Jul 2020Genital coevolution is a pervasive phenomenon as changes in one sex tend to impose fitness consequences on the other, generating sexual conflict. Sexual conflict is...
Genital coevolution is a pervasive phenomenon as changes in one sex tend to impose fitness consequences on the other, generating sexual conflict. Sexual conflict is often thought to cause stronger selection on males due to the Darwin-Bateman's anisogamy paradigm. However, recent studies have demonstrated that female genitalia may be equally elaborated and perform diverse extra-copulatory functions. These characteristics suggest that female genitals can also be primary targets of selection, especially where natural selection acts on female-exclusive functions such as oviposition. Here, we test this hypothesis in a statistical phylogenetic framework across the whole beetle (Coleoptera) phylogeny, investigating whether coevolution of specific genital traits may be triggered by changes in females. We focus on traits of the proctiger, which composes part of the male terminalia and the female ovipositor. Our results present a comprehensive case of male-female genital coevolution and provide solid statistical evidence for a female-initiated coevolutionary process where the vast majority of evolutionary transitions in males have occurred only after changes in females. We corroborate the hypothesis that female traits may change independently and elicit counter-adaptations in males. Furthermore, by showing a consistent pattern across the phylogeny of the most diverse group of animals, our results suggest that this female-driven dynamics may persist through long time scales.
Topics: Animals; Biological Coevolution; Coleoptera; Female; Genitalia; Male; Phylogeny; Selection, Genetic
PubMed: 32277841
DOI: 10.1111/jeb.13627 -
Current Opinion in Insect Science Feb 2018Many traits that are sexually dimorphic, appearing either differently or uniquely in one sex, are also sensitive to an organism's condition. This phenomenon seems to... (Review)
Review
Many traits that are sexually dimorphic, appearing either differently or uniquely in one sex, are also sensitive to an organism's condition. This phenomenon seems to have evolved to limit genetic conflict between traits that are under different selective pressures in each sex. Recent work has shed light on the molecular and developmental mechanisms that govern this condition sensitive growth, and this work has now expanded to encompass both sexual dimorphism as well as conditionally plastic growth, as it seems the two phenomena are linked on a molecular level. In all cases studied the gene doublesex, a conserved regulator of sex differentiation, controls both sexual dimorphism as well as the condition-dependent plastic responses common to these traits. However, the advent of next-generation -omics technologies has allowed researchers to decipher the common and diverged mechanisms of sexually dimorphic plasticity and expand investigations beyond the foundation laid by studies utilizing beetle weapons.
Topics: Adaptation, Physiological; Animals; Coleoptera; Female; Male; Sex Characteristics
PubMed: 29602360
DOI: 10.1016/j.cois.2017.11.009 -
Research in Microbiology Jun 2001Eukaryotic cells, as genetic entities, most often involve several physically associated genomes that direct the metabolic cell equilibrium. In the coleopteran insects of... (Review)
Review
Eukaryotic cells, as genetic entities, most often involve several physically associated genomes that direct the metabolic cell equilibrium. In the coleopteran insects of the genus Sitophilus, in addition to the nucleus and the mitochondrial genomes, two other intracellular bacterial genomes belonging to the alpha and the gamma groups of Proteobacteria are also present. Coexisting with the eukaryotic host cell genomes, they intervene in the physiology and reproduction of the host. They are both transmitted vertically to the progeny and exhibit different levels of symbiont integration in insects. Their coexistence within a eukaryotic cell system illustrates the genetic complexity of animal tissue and questions the concept of the 'biological individual'.
Topics: Animals; Biological Evolution; Coleoptera; DNA, Bacterial; DNA, Mitochondrial; Eukaryotic Cells; Gammaproteobacteria; Genome, Bacterial; Reproduction; Symbiosis; Wolbachia
PubMed: 11446511
DOI: 10.1016/s0923-2508(01)01216-5 -
Genes Aug 2023Tenebrionidae is widely recognized owing to its species diversity and economic importance. Here, we determined the mitochondrial genomes (mitogenomes) of three...
Tenebrionidae is widely recognized owing to its species diversity and economic importance. Here, we determined the mitochondrial genomes (mitogenomes) of three Tenebrionidae species (, , and ) and performed a comparative mitogenomic analysis to characterize the evolutionary characteristics of the family. The tenebrionid mitogenomes were highly conserved with respect to genome size, gene arrangement, base composition, and codon usage. All protein-coding genes evolved under purifying selection. The largest non-coding region (i.e., control region) showed several unusual features, including several conserved repetitive fragments (e.g., A+T-rich regions, G+C-rich regions, Poly-T tracts, TATA repeat units, and longer repetitive fragments) and tRNA-like structures. These tRNA-like structures can bind to the appropriate anticodon to form a cloverleaf structure, although base-pairing is not complete. We summarized the quantity, types, and conservation of tRNA-like sequences and performed functional and evolutionary analyses of tRNA-like sequences with various anticodons. Phylogenetic analyses based on three mitogenomic datasets and two tree inference methods largely supported the monophyly of each of the three subfamilies (Stenochiinae, Pimeliinae, and Lagriinae), whereas both Tenebrioninae and Diaperinae were consistently recovered as polyphyletic. We obtained a tenebrionid mitogenomic phylogeny: (Lagriinae, (Pimeliinae, ((Tenebrioninae + Diaperinae), Stenochiinae))). Our results provide insights into the evolution and function of tRNA-like sequences in tenebrionid mitogenomes and contribute to our general understanding of the evolution of Tenebrionidae.
Topics: Animals; Coleoptera; Phylogeny; RNA, Transfer; Codon Usage; Gene Order
PubMed: 37761878
DOI: 10.3390/genes14091738 -
Proceedings of the National Academy of... Oct 2022Horizontal gene transfer (HGT) provides an evolutionary shortcut for recipient organisms to gain novel functions. Although reports of HGT in higher eukaryotes are...
Horizontal gene transfer (HGT) provides an evolutionary shortcut for recipient organisms to gain novel functions. Although reports of HGT in higher eukaryotes are rapidly accumulating, in most cases the evolutionary trajectory, metabolic integration, and ecological relevance of acquired genes remain unclear. Plant cell wall degradation by HGT-derived enzymes is widespread in herbivorous insect lineages. Pectin is an abundant polysaccharide in the walls of growing parts of plants. We investigated the significance of horizontally acquired pectin-digesting polygalacturonases (PGs) of the leaf beetle . Using a CRISPR/Cas9-guided gene knockout approach, we generated a triple knockout and a quadruple PG-null mutant in order to investigate the enzymatic, biological, and ecological effects. We found that pectin-digestion 1) is exclusively linked to the horizontally acquired PGs from fungi, 2) became fixed in the host genome by gene duplication leading to functional redundancy, 3) compensates for nutrient-poor diet by making the nutritious cell contents more accessible, and 4) facilitates the beetles development and survival. Our analysis highlights the selective advantage PGs provide to herbivorous insects and demonstrate the impact of HGT on the evolutionary success of leaf-feeding beetles, major contributors to species diversity.
Topics: Animals; Coleoptera; Gene Knockout Techniques; Gene Transfer, Horizontal; Pectins; Phylogeny; Plants; Polygalacturonase
PubMed: 36161953
DOI: 10.1073/pnas.2205857119 -
BMC Biology Feb 2022Most of the known genes required for developmental processes have been identified by genetic screens in a few well-studied model organisms, which have been considered...
BACKGROUND
Most of the known genes required for developmental processes have been identified by genetic screens in a few well-studied model organisms, which have been considered representative of related species, and informative-to some degree-for human biology. The fruit fly Drosophila melanogaster is a prime model for insect genetics, and while conservation of many gene functions has been observed among bilaterian animals, a plethora of data show evolutionary divergence of gene function among more closely-related groups, such as within the insects. A quantification of conservation versus divergence of gene functions has been missing, without which it is unclear how representative data from model systems actually are.
RESULTS
Here, we systematically compare the gene sets required for a number of homologous but divergent developmental processes between fly and beetle in order to quantify the difference of the gene sets. To that end, we expanded our RNAi screen in the red flour beetle Tribolium castaneum to cover more than half of the protein-coding genes. Then we compared the gene sets required for four different developmental processes between beetle and fly. We found that around 50% of the gene functions were identified in the screens of both species while for the rest, phenotypes were revealed only in fly (~ 10%) or beetle (~ 40%) reflecting both technical and biological differences. Accordingly, we were able to annotate novel developmental GO terms for 96 genes studied in this work. With this work, we publish the final dataset for the pupal injection screen of the iBeetle screen reaching a coverage of 87% (13,020 genes).
CONCLUSIONS
We conclude that the gene sets required for a homologous process diverge more than widely believed. Hence, the insights gained in flies may be less representative for insects or protostomes than previously thought, and work in complementary model systems is required to gain a comprehensive picture. The RNAi screening resources developed in this project, the expanding transgenic toolkit, and our large-scale functional data make T. castaneum an excellent model system in that endeavor.
Topics: Animals; Coleoptera; Drosophila; Drosophila melanogaster; Pupa; RNA Interference; Tribolium
PubMed: 35135533
DOI: 10.1186/s12915-022-01231-4 -
Philosophical Transactions of the Royal... Dec 2016The evolution of asymmetry in male genitalia is a pervasive and recurrent phenomenon across almost the entire animal kingdom. Although in some taxa the asymmetry may be...
The evolution of asymmetry in male genitalia is a pervasive and recurrent phenomenon across almost the entire animal kingdom. Although in some taxa the asymmetry may be a response to the evolution of one-sided, male-above copulation from a more ancestral female-above condition, in other taxa, such as Mammalia and Coleoptera, this explanation appears insufficient. We carried out an informal assessment of genital asymmetry across the Coleoptera and found that male genital asymmetry is present in 43% of all beetle families, and at all within-family taxonomic levels. In the most diverse group, Cucujiformia, however, genital asymmetry is comparatively rare. We also reconstructed the phylogeny of the leiodid tribe Cholevini, and mapped aspects of genital asymmetry on the tree, revealing that endophallus sclerites, endophallus, median lobe and parameres are, in a nested fashion, increasingly unlikely to have evolved asymmetry. We interpret these results in the light of cryptic female choice versus sexually antagonistic coevolution and advocate further ways in which the phenomenon may be better understood.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.
Topics: Animals; Biological Evolution; Body Patterning; Coleoptera; Genitalia, Male; Male; Phylogeny
PubMed: 27821530
DOI: 10.1098/rstb.2015.0400 -
Journal of Texture Studies Aug 2022The use of insects is considered by Food and Agriculture Organization (FAO) as an alternative source of protein for human and animal food in order to reduce the carbon...
The use of insects is considered by Food and Agriculture Organization (FAO) as an alternative source of protein for human and animal food in order to reduce the carbon footprint caused by meat production and to supply the expected population increase with food. In this regard, the aim of this study was to analyze the physicochemical aspects (water activity, protein and fat content, size, optical and mechanical properties) of biscuits prepared with two different insect powders (Tenebrio molitor [TM] and Alphitobius diaperinus [AD], in different percentages [0, 13, 17, 20, and 25%]) based on total weight. In addition, the biscuits formulated with the highest insect powder content were subjected to sensory analysis. The results revealed that all the biscuits formulated with insect powders may be labeled as "high in protein" products following Regulation (EC) No. 1924/2006, although they were not as thick as the control biscuits. The L* and b* coordinates were significantly lower when the insect powders were included, which implied a darkening of the biscuits, which were also harder than the control biscuits, regardless the concentration used. According to the sensory analysis, most panelists perceived the biscuits containing insects as too dark and not crunchy enough and an increase in sweetness might improve their acceptability. Finally, further studies should be carried out to analyze the influence of different structural components and flavorings, such as chocolate, in the formulation of biscuits with insect powders to improve their sensory attributes.
Topics: Animals; Chocolate; Coleoptera; Flour; Humans; Taste; Tenebrio
PubMed: 35560352
DOI: 10.1111/jtxs.12692 -
Progress in Brain Research 2012Although circannual rhythms controlling different physiological processes and various aspects of behavior have been reported in numerous organisms, our understanding of... (Review)
Review
Although circannual rhythms controlling different physiological processes and various aspects of behavior have been reported in numerous organisms, our understanding of the underlying biological mechanisms is still quite limited. We examined the mechanisms controlling the circannual pupation rhythm of the varied carpet beetle, Anthrenus verbasci. This rhythm is self-sustainable, exhibits temperature compensation of the periodicity, and is entrainable to environmental changes. In addition, the circannual phase response curves to a photoperiod pulse display Type 0 or Type 1 resetting, depending on the duration of the pulse. Thus, we infer that this rhythm is derived from a self-sustaining biological oscillator with a period of about a year, that is, a circannual clock, analogous to the circadian clock. Further, a circadian clock appears to mediate photoperiodic time measurement for phase resetting of the circannual clock. Based on these results and previous research performed in other organisms, we discuss the general characteristics of the physiological mechanisms underpinning circannual rhythmicity.
Topics: Animals; Circadian Rhythm; Coleoptera; Photoperiod; Temperature
PubMed: 22877680
DOI: 10.1016/B978-0-444-59427-3.00025-3