divergence estimates
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2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Juan C. Opazo ◽  
Michael W. Vandewege ◽  
Javier Gutierrez ◽  
Kattina Zavala ◽  
Luis Vargas-Chacoff ◽  
...  

AbstractGolgi phosphoprotein 3 (GOLPH3) was the first reported oncoprotein of the Golgi apparatus. It was identified as an evolutionarily conserved protein upon its discovery about 20 years ago, but its function remains puzzling in normal and cancer cells. The GOLPH3 gene is part of a group of genes that also includes the GOLPH3L gene. Because cancer has deep roots in multicellular evolution, studying the evolution of the GOLPH3 gene family in non-model species represents an opportunity to identify new model systems that could help better understand the biology behind this group of genes. The main goal of this study is to explore the evolution of the GOLPH3 gene family in birds as a starting point to understand the evolutionary history of this oncoprotein. We identified a repertoire of three GOLPH3 genes in birds. We found duplicated copies of the GOLPH3 gene in all main groups of birds other than paleognaths, and a single copy of the GOLPH3L gene. We suggest there were at least three independent origins for GOLPH3 duplicates. Amino acid divergence estimates show that most of the variation is located in the N-terminal region of the protein. Our transcript abundance estimations show that one paralog is highly and ubiquitously expressed, and the others were variable. Our results are an example of the significance of understanding the evolution of the GOLPH3 gene family, especially for unraveling its structural and functional attributes.


2021 ◽  
Author(s):  
Tim Fischer ◽  
Johannes Karstensen ◽  
Marcus Dengler ◽  
Arne Bendinger

<p>During the collaborative project "Role of Eddies in the Carbon Pump of Eastern Boundary </p><p>Upwelling Systems" (REEBUS), that took place in the eastern tropical North Atlantic in 2019, </p><p>three cyclonic mesoscale eddies were intensely surveyed by ship and autonomous systems. The </p><p>three eddies were located at different distances to the coast, the most intense of them </p><p>(vorticity about 0.5 times f) was found in lee of the Cabo Verdian island of Fogo. Here we </p><p>present the reconstruction of the 3-D structure for the three eddies from ship ADCP and </p><p>hydrographic sections. Divergence estimates suggest the existence of a downwelling cell in the </p><p>center of all three eddies. This cell extends from below the thermocline down to some hundred </p><p>meters, at a diameter of about 10 nautical miles. Surface signatures of the eddies indicate </p><p>elliptic and oscillating behavior which is further investigated using the interior ocean data. </p><p>In this work we also explore the limitations of section-based ocean mesoscale eddy </p><p>reconstructions.</p>


Life ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 181
Author(s):  
Nicola Zadra ◽  
Annapaola Rizzoli ◽  
Omar Rota-Stabelli

One-third of all mosquitoes belong to the Aedini, a tribe comprising common vectors of viral zoonoses such as Aedes aegypti and Aedes albopictus. To improve our understanding of their evolution, we present an updated multigene estimate of Aedini phylogeny and divergence, focusing on the disentanglement between nuclear and mitochondrial phylogenetic signals. We first show that there are some phylogenetic discrepancies between nuclear and mitochondrial markers which may be caused by wrong taxa assignment in samples collections or by some stochastic effect due to small gene samples. We indeed show that the concatenated dataset is model and framework dependent, indicating a general paucity of signal. Our Bayesian calibrated divergence estimates point toward a mosquito radiation in the mid-Jurassic and an Aedes radiation from the mid-Cretaceous on. We observe, however a strong chronological incongruence between mitochondrial and nuclear data, the latter providing divergence times within the Aedini significantly younger than the former. We show that this incongruence is consistent over different datasets and taxon sampling and that may be explained by either peculiar evolutionary event such as different levels of saturation in certain lineages or a past history of hybridization throughout the genus. Overall, our updated picture of Aedini phylogeny, reveal a strong nuclear-mitochondrial incongruence which may be of help in setting the research agenda for future phylogenomic studies of Aedini mosquitoes.


2021 ◽  
Author(s):  
Juan C. Opazo ◽  
Michael W. Vandewege ◽  
Javier Gutierrez ◽  
Kattina Zavala ◽  
Luis Vargas-Chacoff ◽  
...  

AbstractGolgi phosphoprotein 3 (GOLPH3) is considered the first oncoprotein of the Golgi apparatus. It was identified as an evolutionarily conserved protein upon its discovery about 20 years ago, but its function remains puzzling in normal and cancer cells. The GOLPH3 gene is part of a group of genes that also includes the GOLPH3L gene. Because cancer has deep roots in multicellular evolution, studying the evolution of the GOLPH3 gene family in non-model species represents an opportunity to identify new model systems that could help better understand the biology behind this group of genes. The main goal of this study is to explore the evolution of the GOLPH3 gene family in birds as a starting point to understand the evolutionary history of this oncoprotein. We identified a repertoire of three GOLPH3 genes in birds. We found duplicated copies of the GOLPH3 gene in all main groups of birds other than paleognaths, and a single copy of the GOLPH3L gene. We suggest there were at least three independent origins for GOLPH3 duplicates. Amino acid divergence estimates show that most of the variation is located in the N-terminal region of the protein. Our transcript abundance estimations show that one paralog is highly and ubiquitously expressed, and the others were variable. Our results are an example of the significance of understanding the evolution of the GOLPH3 gene family, especially for unraveling its structural and functional attributes.


ZooKeys ◽  
2020 ◽  
Vol 1008 ◽  
pp. 1-15
Author(s):  
Chao Huang ◽  
Shane T. Ahyong ◽  
Hsi-Te Shih

A new genus and new species of blind freshwater cave crab are described from Chongzuo City, Guangxi Zhuang Autonomous Region, China based on morphology and mitochondrial 16S rDNA sequences. The new genus, Phasmongen. nov., is established for P. typhlopssp. nov., which is only the second blind cave crab known from China and East Asia. The combination of a very wide carapace, overall depigmentation, reduced orbits and vestigial unpigmented eyes of Phasmon immediately separates it from all known potamid genera. Molecular divergence estimates based on 16S rDNA suggest that the lineage to which the new genus belongs diverged from other potamids at the beginning of the Late Miocene (10.8 million years ago), much earlier than other Chinese cave crabs.


2020 ◽  
Vol 9 (2) ◽  
pp. 244
Author(s):  
Sherzad M. Ajeel ◽  
Hussein A. Hashem

In this paper, we reviewed some variable selection methods in linear regression model. Conventional methodologies such as the Ordinary Least Squares (OLS) technique is one of the most commonly used method in estimating the parameters in linear regression. But the OLS estimates performs poorly when the dataset suffer from outliers or when the assumption of normality is violated such as in the case of heavy-tailed errors. To address this problem, robust regularized regression methods like Huber Lasso (Rosset and Zhu, 2007) and quantile regression (Koenker and Bassett ,1978] were proposed. This paper focuses on comparing the performance of the seven methods, the quantile regression estimates, the Huber Lasso estimates, the adaptive Huber Lasso estimates, the adaptive LAD Lasso, the Gamma-divergence estimates, the Maximum Tangent Likelihood Lasso (MTE) estimates and Semismooth Newton Coordinate Descent Algorithm (SNCD ) Huber loss estimates.


Author(s):  
Tyler K. Chafin ◽  
Marlis R. Douglas ◽  
Michael E. Douglas

AbstractHybridization is well recognized as a driver of speciation, yet it often remains difficult to parse phylogenomically in that post-speciation gene flow frequently supersedes an ancestral signal. Here we examined how interactions between recombination and gene flow shaped the phylogenomic landscape of red wolf to create non-random retention of introgressed ancestry. Our re-analyses of genomic data recapitulate fossil evidence by demonstrating red wolf was indeed extant and isolated prior to more recent admixture with other North American canids. Its more ancient divergence, now sequestered within low-recombinant regions on the X-chromosome (i.e., chromosomal ‘refugia’), is effectively masked by multiple, successive waves of secondary introgression that now dominate its autosomal ancestry. These interpretations are congruent with more theoretical explanations that describe the manner by which introgression can be localized within the genome through recombination and selection. They also tacitly support the large-X effect, i.e., the manner by which loci that contribute to reproductive isolation can be enriched on the X-chromosome. By contrast, similar, high recombinant regions were also found as enriched within very shallow gene trees, thus reflecting post-speciation gene flow and a compression of divergence estimates to 1/20th of that found in recombination ‘cold spots’. Our results effectively reconcile conflicting hypotheses regarding the impact of hybridization on evolution of North American canids and support an emerging framework within which the analysis of a phylogenomic landscape structured by recombination can be used to successfully address the macroevolutionary implications of hybridization.


Author(s):  
Ben A. Parslow ◽  
John T. Jennings ◽  
Michael P. Schwarz ◽  
Mark I. Stevens

The Gasteruptiidae are an easily recognised family of wasps whose larvae are considered predator-inquilines in the nests of solitary bees and wasps. There has been minimal molecular research on the family and as a result little understanding of the evolutionary relationships within the group. We present the first molecular phylogeny focused on Gasteruptiidae, generated using three molecular fragments (mitochondrial C01 and nuclear markers EF1-α and 28s) and estimate the divergence times of Evanioidea based on three secondary calibration points. The analyses included 142 specimens of Gasteruptiidae and 5 outgroup taxa from Aulacidae and Evaniidae. The monophyly of the Gasteruptiidae and its subfamilies Gasteruptiinae (Gasteruption) and Hyptiogastrinae (Hyptiogaster and Pseudofoenus) are confirmed. Our results indicate that Evanioidea diverged during the late Jurassic at 151.3 (171.99–136.15)Ma with Evaniidae during the early Cretaceous at 137.33 (140.86–133.67)Ma, and Gasteruptiidae during the Palaeocene at 60.23 (83.78–40.02)Ma. The crown age of Hyptiogastrinae was estimated to be during the mid-Eocene 40.72 (60.9–22.57)Ma and for Gasteruption during the early Eocene at 47.46 (64.7–31.75)Ma, which corresponded to their host divergence ages. We anticipate that more extensive taxon sampling combined with the use of phylogenomic data will help resolve low support within the Gasteruption clade.


2019 ◽  
Vol 190 (1) ◽  
pp. 352-371 ◽  
Author(s):  
Hesham M Sallam ◽  
Erik R Seiffert

Abstract ‘Paraphiomys’ simonsi is a phiomorph rodent from the early Oligocene of Egypt (~29–30 Mya) that has historically been aligned with much younger (< ~20 Mya) Miocene species of the genera Paraphiomys and Neosciuromys. Here, we use Bayesian tip-dating analysis of a 109-character morphological matrix containing 57 living and extinct ctenohystricans to test these proposed placements for ‘Paraphiomys’ simonsi. Our analyses provide support for the exclusion of ‘Paraphiomys’ simonsi from both Paraphiomys and Neosciuromys and justify the establishment of a new genus (Monamys gen. nov.) for this stem thryonomyoid. These analyses also indicate that the divergence of the extant dassie rat Petromus from the extant cane rat Thryonomys (i.e. origin of crown Thryonomyoidea) occurred ~23.7 Mya, close to the Oligocene–Miocene boundary and in close agreement with recent molecular estimates for this split. Miocene Neosciuromys, Paraulacodus, Protohummus and the type species of Paraphiomys are identified as stem thryonomyids, whereas the Namibian species Apodecter stromeri, Tufamys woodi, ‘Paraphiomys’ australis and ‘Paraphiomys’ roessneri are identified for the first time as stem petromurids, raising the possibility of a long period of endemic petromurid evolution in south-west Africa. Comparison of molecular divergence estimates with our optimal tip-dated topology suggests that stem bathyergoids are most likely to have arisen from late Eocene and early Oligocene ‘phiomyids’.


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