scholarly journals Root Digger: a root placement program for phylogenetic trees

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Ben Bettisworth ◽  
Alexandros Stamatakis
Keyword(s):  
Phylogenetic Analysis ◽  
Markov Model ◽  
Molecular Clock ◽  
Phylogenetic Trees ◽  
Markov Models ◽  
Root Position ◽  
Clock Analysis ◽  
Confidence Value ◽  
Root Location ◽  
Molecular Clock Analysis

Abstract Background In phylogenetic analysis, it is common to infer unrooted trees. However, knowing the root location is desirable for downstream analyses and interpretation. There exist several methods to recover a root, such as molecular clock analysis (including midpoint rooting) or rooting the tree using an outgroup. Non-reversible Markov models can also be used to compute the likelihood of a potential root position. Results We present a software called which uses a non-reversible Markov model to compute the most likely root location on a given tree and to infer a confidence value for each possible root placement. We find that is successful at finding roots when compared to similar tools such as IQ-TREE and MAD, and will occasionally outperform them. Additionally, we find that the exhaustive mode of is useful in quantifying and explaining uncertainty in rooting positions. Conclusions can be used on an existing phylogeny to find a root, or to asses the uncertainty of the root placement. is available under the MIT licence at https://www.github.com/computations/root_digger.

scholarly journals RootDigger: a root placement program for phylogenetic trees

2020 ◽  
Author(s):  
Ben Bettisworth ◽  
Alexandros Stamatakis
Keyword(s):  
Phylogenetic Analysis ◽  
Markov Model ◽  
Phylogenetic Trees ◽  
Common Ancestor ◽  
Markov Models ◽  
Recent Common Ancestor ◽  
Most Recent Common Ancestor ◽  
Root Position ◽  
Confidence Value ◽  
Root Location

AbstractSummaryIn phylogenetic analysis, it is common to infer unrooted trees. Thus, it is unknown which node is the most recent common ancestor of all the taxa in the phylogeny. However, knowing the root location is desirable for downstream analyses and interpretation. There exist several methods to recover a root, such as midpoint rooting or rooting the tree at an outgroup. Non-reversible Markov models can also be used to compute the likelihood of a potential root position. We present a software called RootDigger which uses a non-reversible Markov model to compute the most likely root location on a given tree and to infer a confidence value for each possible root placement.Availability and implementationRootDigger is available under the MIT licence at https://github.com/computations/root_digger

Late Miocene eastwards transatlantic dispersal of flightless anchonine weevils (Coleoptera: Curculionidae: Molytinae)

Zootaxa ◽  
2021 ◽  
Vol 4952 (1) ◽  
pp. 55-70
Author(s):  
VASILY V. GREBENNIKOV ◽  
ROBERT S. ANDERSON
Keyword(s):  
Phylogenetic Analysis ◽  
Atlantic Ocean ◽  
Molecular Clock ◽  
Molecular Data ◽  
West African ◽  
The West ◽  
Incertae Sedis ◽  
Clock Analysis ◽  
Morphological And Molecular Data ◽  
Molecular Clock Analysis

The weevil genera Aethiopacorep Voisin and Titilayo Cristóvão & Lyal are the only native African members of the nearly pantropical and poorly known tribe Anchonini. All Anchonini are flightless, a trait likely limiting dispersal, yet these weevils are found on both sides of the Atlantic Ocean. A phylogenetic analysis of 79 terminals and 3248 aligned positions from one mitochondrial and two nuclear ribosomal fragments supports a clade of West African Anchonini nested within American Anchonini. As suggested by previous authors, the Asian genera Himalanchonus Zherikhin and Otibazo Morimoto do not form a clade with the tribe’s core, and along with Cycloterinus Kolbe, Euthycodes Pascoe, Leptanchonus Morimoto, Nepalanchonus Zherikhin, and Tanyomus Champion, are here removed from Anchonini and placed as Molytinae incertae sedis. So defined, the monophyletic tribe Anchonini contains 36 genus-group names, all but two denoting American taxa. Using molecular clock analysis, we estimate the separation of the West African Anchonini from its American sister at 9.5–5.2 million years ago (Ma). This date greatly postdates the Cretaceous opening of the Atlantic Ocean (about 100 Ma) and, therefore, evokes a single transatlantic dispersal to West Africa, likely by over-water rafting, leading to subsequent diversification. We postulate this to be the first documented eastwards crossing of the Atlantic Ocean by terrestrial non-volant arthropods based on morphological and molecular data. 

scholarly journals Genomics and epidemiology of the P.1 SARS-CoV-2 lineage in Manaus, Brazil

Science ◽  
2021 ◽  
pp. eabh2644 ◽  
Author(s):  
Nuno R. Faria ◽  
Thomas A. Mellan ◽  
Charles Whittaker ◽  
Ingra M. Claro ◽  
Darlan da S. Candido ◽  
...  
Keyword(s):  
Molecular Evolution ◽  
Genome Sequencing ◽  
Immune Evasion ◽  
Molecular Clock ◽  
Spike Protein ◽  
Dynamical Model ◽  
Mortality Data ◽  
Clock Analysis ◽  
Protection Against Infection ◽  
Molecular Clock Analysis

Cases of SARS-CoV-2 infection in Manaus, Brazil, resurged in late 2020, despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1, acquired 17 mutations, including a trio in the spike protein (K417T, E484K and N501Y) associated with increased binding to the human ACE2 receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7–2.4-fold more transmissible, and that previous (non-P.1) infection provides 54–79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.

scholarly journals Complete Genomic Sequence of Human Coronavirus OC43: Molecular Clock Analysis Suggests a Relatively Recent Zoonotic Coronavirus Transmission Event

2005 ◽  
Vol 79 (3) ◽  
pp. 1595-1604 ◽  
Author(s):  
Leen Vijgen ◽  
Els Keyaerts ◽  
Elien Moës ◽  
Inge Thoelen ◽  
Elke Wollants ◽  
...  
Keyword(s):  
Molecular Clock ◽  
Complete Genome ◽  
Recent Common Ancestor ◽  
Human Coronavirus ◽  
Transmission Event ◽  
Most Recent Common Ancestor ◽  
A Genome ◽  
Clock Analysis ◽  
Group 2 ◽  
Molecular Clock Analysis

ABSTRACT Coronaviruses are enveloped, positive-stranded RNA viruses with a genome of approximately 30 kb. Based on genetic similarities, coronaviruses are classified into three groups. Two group 2 coronaviruses, human coronavirus OC43 (HCoV-OC43) and bovine coronavirus (BCoV), show remarkable antigenic and genetic similarities. In this study, we report the first complete genome sequence (30,738 nucleotides) of the prototype HCoV-OC43 strain (ATCC VR759). Complete genome and open reading frame (ORF) analyses were performed in comparison to the BCoV genome. In the region between the spike and membrane protein genes, a 290-nucleotide deletion is present, corresponding to the absence of BCoV ORFs ns4.9 and ns4.8. Nucleotide and amino acid similarity percentages were determined for the major HCoV-OC43 ORFs and for those of other group 2 coronaviruses. The highest degree of similarity is demonstrated between HCoV-OC43 and BCoV in all ORFs with the exception of the E gene. Molecular clock analysis of the spike gene sequences of BCoV and HCoV-OC43 suggests a relatively recent zoonotic transmission event and dates their most recent common ancestor to around 1890. An evolutionary rate in the order of 4 × 10−4 nucleotide changes per site per year was estimated. This is the first animal-human zoonotic pair of coronaviruses that can be analyzed in order to gain insights into the processes of adaptation of a nonhuman coronavirus to a human host, which is important for understanding the interspecies transmission events that led to the origin of the severe acute respiratory syndrome outbreak.

Molecular clock analysis

2012 ◽  
pp. 362-380 ◽  
Author(s):  
Philippe Lemey ◽  
David Posada
Keyword(s):  
Molecular Clock ◽  
Clock Analysis ◽  
Molecular Clock Analysis

scholarly journals A novel, divergent simian T-cell lymphotropic virus type 3 in a wild-caught red-capped mangabey (Cercocebus torquatus torquatus) from Nigeria

2003 ◽  
Vol 84 (10) ◽  
pp. 2723-2727 ◽  
Author(s):  
L. Meertens ◽  
V. Shanmugam ◽  
A. Gessain ◽  
B. E. Beer ◽  
Z. Tooze ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
T Cell ◽  
Western Blot ◽  
Wide Distribution ◽  
African Origin ◽  
Cercocebus Torquatus ◽  
African Populations ◽  
Clock Analysis ◽  
Type 3 ◽  
Molecular Clock Analysis

We present here a novel, distinct simian T-cell lymphotropic virus (STLV) found in a red-capped mangabey (Cercocebus torquatus) (CTO-NG409), wild-caught in Nigeria, that showed an HTLV-2-like Western blot (WB) seroreactivity. The complete genome (8920 bp) of CTO-NG409 STLV was related to but different from STLV-3/PHA-PH969 (13·5 %) and STLV-3/PPA-F3 (7·6 %), and STLV-3/CTO604 (11·3 %), found in Eritrean and Senegalese baboons, and red-capped mangabeys from Cameroon, respectively. Phylogenetic analysis of a conserved tax (180 bp) sequence and the env gene (1482 bp) confirmed the relatedness of STLV-3/CTO-NG409 to the STLV-3 subgroup. Molecular clock analysis of env estimated that STLV-3/CTO-NG409 diverged from East and West/Central African STLV-3s about 140 900±12 400 years ago, suggesting an ancient African origin of STLV-3. Since phylogenetic evidence suggests multiple interspecies transmissions of STLV-1 to humans, and given the antiquity and wide distribution of STLV-3 in Africa, a search for STLV-3 in human African populations with HTLV-2-like WB patterns is warranted.

scholarly journals Assessing Confidence in Root Placement on Phylogenies: An Empirical Study Using Non-Reversible Models

2020 ◽  
Author(s):  
Suha Naser-Khdour ◽  
Bui Quang Minh ◽  
Robert Lanfear
Keyword(s):  
Phylogenetic Analysis ◽  
Empirical Study ◽  
Computational Efficiency ◽  
Empirical Data ◽  
Markov Models ◽  
External Information ◽  
Molecular Clocks ◽  
Statistical Support ◽  
Root Position ◽  
High Computational Efficiency

AbstractUsing time-reversible Markov models is a very common practice in phylogenetic analysis, because although we expect many of their assumptions to be violated by empirical data, they provide high computational efficiency. However, these models lack the ability to infer the root placement of the estimated phylogeny. In order to compensate for the inability of these models to root the tree, many researchers use external information such as using outgroup taxa or additional assumptions such as molecular-clocks. In this study, we investigate the utility of non-reversible models to root empirical phylogenies and introduce a new bootstrap measure, the rootstrap, which provides information on the statistical support for any given root position.Availability and implementationA python script for calculating rootstrap support values is available at https://github.com/suhanaser/Rootstrap.

scholarly journals Molecular Evolution of Puumala Hantavirus

2001 ◽  
Vol 75 (23) ◽  
pp. 11803-11810 ◽  
Author(s):  
Tarja Sironen ◽  
Antti Vaheri ◽  
Alexander Plyusnin
Keyword(s):  
Phylogenetic Analysis ◽  
Molecular Evolution ◽  
Genetic Variants ◽  
Rna Virus ◽  
Puumala Virus ◽  
Genetic Lineages ◽  
Clock Analysis ◽  
Geographical Clustering ◽  
The Individual ◽  
Molecular Clock Analysis

ABSTRACT Puumala virus (PUUV) is a negative-stranded RNA virus in the genusHantavirus, family Bunyaviridae. In this study, detailed phylogenetic analysis was performed on 42 complete S segment sequences of PUUV originated from several European countries, Russia, and Japan, the largest set available thus far for hantaviruses. The results show that PUUV sequences form seven distinct and well-supported genetic lineages; within these lineages, geographical clustering of genetic variants is observed. The overall phylogeny of PUUV is star-like, suggesting an early split of genetic lineages. The individual PUUV lineages appear to be independent, with the only exception to this being the Finnish and the Russian lineages that are closely connected to each other. Two strains of PUUV-like virus from Japan form the most ancestral lineage diverging from PUUV. Recombination points within the S segment were searched for and evidence for intralineage recombination events was seen in the Finnish, Russian, Danish, and Belgian lineages of PUUV. Molecular clock analysis showed that PUUV is a stable virus, evolving slowly at a rate of 0.7 × 10−7 to 2.2 × 10−6 nt substitutions per site per year.

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