scholarly journals Evolutionary history and classification of Micropia retroelements in Drosophilidae species

2019 ◽  
Author(s):  
Juliana Cordeiro ◽  
Tuane L. Carvalho ◽  
Vera L. da S. Valente ◽  
Lizandra J. Robe

AbstractCurrent knowledge indicates TEs have been shaping the evolution of genomes and host species, contributing to the creation of new genes and promoting rearrangements frequently associated with new regulatory networks. Support for these hypothesis frequently result from studies with model species, and Drosophila detaches as a great model organism to the study of TEs. Micropia belongs to the Ty3/Gypsy group of LTR retroelements, and comprises one of the least studied Drosophila transposable elements. In this study, we assessed the evolutionary history of Micropia within Drosophilidae, while trying to assist in the classification of this TE. At first, we analyzed its presence in the genome of several species from natural populations and then, based on searches within genomic databases, we retrieved Micropia-like sequences from distinct Drosophilidae species genomes. We expanded the knowledge of Micropia distribution within Drosophila, and detected an array of divergent sequences, which allowed subdividing this retroelement in 20 subfamilies. Even so, a patchy distribution of Micropia sequences within the Drosophilidae phylogeny could be identified combined with incongruences of the species and the Micropia phylogenies. Comparing dS values between Micropia and host nuclear sequences, we found several cases of unexpected high levels of similarity between Micropia sequences found in divergent species. All these findings propose a hypothesis to the evolution of Micropia within Drosophilidae, including several VTTs and HTTs events, associated to ancestral polymorphisms and recurrent Micropia sequences diversification.

Genetics ◽  
1996 ◽  
Vol 142 (2) ◽  
pp. 579-585 ◽  
Author(s):  
Volker Knoop ◽  
Michael Unseld ◽  
Joachim Marienfeld ◽  
Petra Brandt ◽  
Sabine Sünkel ◽  
...  

Abstract Several retrotransposon fragments are integrated in the mitochondrial genome of Arabidopsis thaliana. These insertions are derived from all three classes of nuclear retrotransposons, the Tyl/copia, Ty3/gypsy- and non-LTR/LINE-families. Members of the Ty3/gypsy group of elements have not yet been identified in the nuclear genome of Arabidopsis. The varying degrees of similarity with nuclear elements and the dispersed locations of the sequences in the mitochondrial genome suggest numerous independent transfer-insertion events in the evolutionary history of this plant mitochondrial genome. Overall, we estimate remnants of retrotransposons to cover ≥5% of the mitochondrial genome in Arabidopsis.


Author(s):  
Gordon Grigg ◽  
David Kirshner

Biology and Evolution of Crocodylians is a comprehensive review of current knowledge about the world's largest and most famous living reptiles. Gordon Grigg's authoritative and accessible text and David Kirshner's stunning interpretive artwork and colour photographs combine expertly in this contemporary celebration of crocodiles, alligators, caimans and gharials. This book showcases the skills and capabilities that allow crocodylians to live how and where they do. It covers the biology and ecology of the extant species, conservation issues, crocodylian–human interaction and the evolutionary history of the group, and includes a vast amount of new information; 25 per cent of 1100 cited publications have appeared since 2007. Richly illustrated with more than 500 colour photographs and black and white illustrations, this book will be a benchmark reference work for crocodylian biologists, herpetologists and vertebrate biologists for years to come. Winner of the 2015 Whitley Medal.


2013 ◽  
Vol 39 (6) ◽  
pp. 728-741 ◽  
Author(s):  
Daniel Antunes Silva Pereira ◽  
Alexandre de Melo Kawassaki ◽  
Bruno Guedes Baldi

The initial evaluation of patients with interstitial lung disease (ILD) primarily involves a comprehensive, active search for the cause. Autoantibody assays, which can suggest the presence of a rheumatic disease, are routinely performed at various referral centers. When interstitial lung involvement is the condition that allows the definitive diagnosis of connective tissue disease and the classical criteria are met, there is little debate. However, there is still debate regarding the significance, relevance, specificity, and pathophysiological role of autoimmunity in patients with predominant pulmonary involvement and only mild symptoms or formes frustes of connective tissue disease. The purpose of this article was to review the current knowledge of autoantibody positivity and to discuss its possible interpretations in patients with ILD and without clear etiologic associations, as well as to enhance the understanding of the natural history of an allegedly new disease and to describe the possible prognostic implications. We also discuss the proposition of a new term to be used in the classification of ILDs: lung-dominant connective tissue disease.


2010 ◽  
Vol 33 (5) ◽  
pp. 402-403 ◽  
Author(s):  
Robert M. Seyfarth ◽  
Dorothy L. Cheney

AbstractAmong monkeys and apes, both the recognition and classification of individuals and the recognition and classification of vocalizations constitute discrete combinatorial systems. One system maps onto the other, suggesting that during human evolution kinship classifications and language shared a common cognitive precursor.


2007 ◽  
Vol 35 (5) ◽  
pp. 724-730 ◽  
Author(s):  
EH Kayias ◽  
GI Drosos ◽  
KI Kazakos ◽  
C Iatrou ◽  
KS Blatsoukas ◽  
...  

We report the rare case of a histologically proven mixed-type intramuscular haemangioma, adjacent to the periosteum of the radius, that caused a periosteal reaction. We also carried out a review of the literature relevant to this case. A 28-year-old male professional drummer presented with an 8-month history of pain and swelling of the dorsal aspect of the right radius. Diagnosis was established on the basis of plain radiographs and magnetic resonance imaging, and was confirmed by histology. The lesion was treated solely by resection of the soft-tissue mass. The patient remained asymptomatic 4 years post-operatively, with no radiographic signs of recurrence. From a review of the literature, it is evident that the terminology for haemangiomas causing regional bone changes is unclear. A new classification of the intramuscular haemangiomas is proposed in order to distinguish between lesions that, according to current knowledge, exhibit radiological and clinical areas of overlap.


2021 ◽  
Author(s):  
Haifeng Zhang ◽  
Renjie Shang ◽  
Kwantae Kim ◽  
Wei Zheng ◽  
Christopher J. Johnson ◽  
...  

The size of an animal is determined by the size of its musculoskeletal system. Myoblast fusion is an innovative mechanism that allows for multinucleated muscle fibers to compound the size and strength of individual mononucleated cells. However, the evolutionary history of the control mechanism underlying this important process is currently unknown. The phylum Chordata hosts closely related groups that span distinct myoblast fusion states: no fusion in cephalochordates, restricted fusion and multinucleation in tunicates, and extensive, obligatory fusion in vertebrates. To elucidate how these differences may have evolved, we studied the evolutionary origins and function of membrane-coalescing agents Myomaker and Myomixer in various groups of chordates. Here we report that Myomaker likely arose through gene duplication in the last common ancestor of tunicates and vertebrates, while Myomixer appears to have evolved de novo in early vertebrates. Functional tests revealed an unexpectedly complex evolutionary history of myoblast fusion in chordates. A pre-vertebrate phase of muscle multinucleation driven by Myomaker was followed by the later emergence of Myomixer that enables the highly efficient fusion system of vertebrates. Thus, our findings reveal the evolutionary origins of chordate-specific fusogens and illustrate how new genes can shape the emergence of novel morphogenetic traits and mechanisms.


2019 ◽  
Author(s):  
Andrew D. Foote ◽  
Michael D. Martin ◽  
Marie Louis ◽  
George Pacheco ◽  
Kelly M. Robertson ◽  
...  

AbstractReconstruction of the demographic and evolutionary history of populations assuming a consensus tree-like relationship can mask more complex scenarios, which are prevalent in nature. An emerging genomic toolset, which has been most comprehensively harnessed in the reconstruction of human evolutionary history, enables molecular ecologists to elucidate complex population histories. Killer whales have limited extrinsic barriers to dispersal and have radiated globally, and are therefore a good candidate model for the application of such tools. Here, we analyse a global dataset of killer whale genomes in a rare attempt to elucidate global population structure in a non-human species. We identify a pattern of genetic homogenisation at lower latitudes and the greatest differentiation at high latitudes, even between currently sympatric lineages. The processes underlying the major axis of structure include high drift at the edge of species’ range, likely associated with founder effects and allelic surfing during post-glacial range expansion. Divergence between Antarctic and non-Antarctic lineages is further driven by ancestry segments with up to four-fold older coalescence time than the genome-wide average; relicts of a previous vicariance during an earlier glacial cycle. Our study further underpins that episodic gene flow is ubiquitous in natural populations, and can occur across great distances and after substantial periods of isolation between populations. Thus, understanding the evolutionary history of a species requires comprehensive geographic sampling and genome-wide data to sample the variation in ancestry within individuals.


2019 ◽  
Vol 104 (1) ◽  
pp. 69-82 ◽  
Author(s):  
Mónica M. Carlsen ◽  
Thomas B. Croat

This study presents an evaluation of the currently accepted sectional classification of the genus Anthurium Schott (Araceae) in light of a recently published molecular phylogeny for the group. In general, disagreements between these two occur because many diagnostic morphological characters used in the sectional classification turned out to be highly homoplasious within Anthurium, with multiple independent gains or losses of seemingly similar morphologies in distantly related clades. A new sectional classification of Anthurium that more accurately represents species relationships and the evolutionary history of the genus is much needed, and here we propose the first steps toward it. Results from this study suggest that out of the 18 sections and two series recognized in Anthurium, only seven of these groups are monophyletic (i.e., sections Andiphilum (Schott) Croat, Calomystrium (Schott) Engl., Dactylophyllium (Schott) Engl., Leptanthurium (Schott) Engl., Polyphyllium Engl., Tetraspermium (Schott) Engl., and the newly recognized section Multinervia (Croat) Carlsen & Croat, previously a series within section Pachyneurium (Schott) Engl.). All other sections are either not monophyletic or their monophyly could not be accurately tested. A complete revision of the sectional classification of Anthurium will require a more comprehensive taxon sampling and a better supported molecular phylogeny.


Author(s):  
Mansi Srivastava

The majority of animal phyla have species that can regenerate. Comparing regeneration across animals can reconstruct the molecular and cellular evolutionary history of this process. Recent studies have revealed some similarity in regeneration mechanisms, but rigorous comparative methods are needed to assess whether these resemblances are ancestral pathways (homology) or are the result of convergent evolution (homoplasy). This review aims to provide a framework for comparing regeneration across animals, focusing on gene regulatory networks (GRNs), which are substrates for assessing process homology. The homology of the wound-induced activation of Wnt signaling and of adult stem cells are discussed as examples of ongoing studies of regeneration that enable comparisons in a GRN framework. Expanding the study of regeneration GRNs in currently studied species and broadening taxonomic sampling for these approaches will identify processes that are unifying principles of regeneration biology across animals. These insights are important both for evolutionary studies of regeneration and for human regenerative medicine. Expected final online publication date for the Annual Review of Cell and Developmental Biology, Volume 37 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


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