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Phylogeny and antiquity of M macrohaplogroup inferred from complete mt DNA sequence of Indian specific lineages
Revathi Rajkumar, Jheelam Banerjee, Hima Gunturi, R Trivedi, VK Kashyap
BMC Evolutionary Biology , 2005, DOI: 10.1186/1471-2148-5-26
Abstract: The phylogenetic tree constructed from sequencing information of twenty-four whole mtDNA genome revealed novel substitutions in the previously defined M2a and M6 lineages. The most striking feature of this phylogenetic tree is the recognition of two new lineages, M30 and M31, distinguished by transitions at 12007 and 5319, respectively. M30 comprises of M18 and identifies a potential new sub-lineage possessing substitution at 16223 and 16300. It further branches into M30a sub-lineage, defined by 15431 and 195A substitution. The age of M30 lineage was estimated at 33,042 YBP, indicating a more recent expansion time than M2 (49,686 YBP). The M31 branch encompasses the M6 lineage along with the previously defined M3 and M4 lineages. Contradictory to earlier reports, the M5 lineage does not always include a 12477 substitution, and is more appropriately defined by a transversion at 10986A. The phylogenetic tree also identifies a potential new lineage in the M* branch with HVSI sequence as 16223,16325. Substitutions in M25 were in concordance with previous reports.This study describes five new basal mutations and recognizes two new lineages, M30 and M31 that substantially contribute to the present understanding of macrohaplogroup M. These two newly erected lineages include the previously independent lineages M18 and M6 as sub-lineages within them, respectively, suggesting that most mt DNA genomes might arise as limited offshoots of M trunk. Furthermore, this study supports the non existence of lineages such as M3 and M4 that are solely defined on the basis of fast mutating control region motifs and hence, establishes the importance of coding region markers for an accurate understanding of the phylogeny. The deep roots of M phylogeny clearly establish the antiquity of Indian lineages, especially M2, as compared to Ethiopian M1 lineage and hence, support an Asian origin of M majorhaplogroup.During the last few years a surge in information on mitochondrial DNA control region
A Mitogenomic Re-Evaluation of the Bdelloid Phylogeny and Relationships among the Syndermata  [PDF]
Erica Lasek-Nesselquist
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0043554
Abstract: Molecular and morphological data regarding the relationships among the three classes of Rotifera (Bdelloidea, Seisonidea, and Monogononta) and the phylum Acanthocephala are inconclusive. In particular, Bdelloidea lacks molecular-based phylogenetic appraisal. I obtained coding sequences from the mitochondrial genomes of twelve bdelloids and two monogononts to explore the molecular phylogeny of Bdelloidea and provide insight into the relationships among lineages of Syndermata (Rotifera + Acanthocephala). With additional sequences taken from previously published mitochondrial genomes, the total dataset included nine species of bdelloids, three species of monogononts, and two species of acanthocephalans. A supermatrix of these 10–12 mitochondrial proteins consistently recovered a bdelloid phylogeny that questions the validity of a generally accepted classification scheme despite different methods of inference and various parameter adjustments. Specifically, results showed that neither the family Philodinidae nor the order Philodinida are monophyletic as currently defined. The application of a similar analytical strategy to assess syndermate relationships recovered either a tree with Bdelloidea and Monogononta as sister taxa (Eurotatoria) or Bdelloidea and Acanthocephala as sister taxa (Lemniscea). Both outgroup choice and method of inference affected the topological outcome emphasizing the need for sequences from more closely related outgroups and more sophisticated methods of analysis that can account for the complexity of the data.
Site specific rates of mitochondrial genomes and the phylogeny of eutheria
Karl M Kjer, Rodney L Honeycutt
BMC Evolutionary Biology , 2007, DOI: 10.1186/1471-2148-7-8
Abstract: Mitochondrial genomic data for 78 eutherian mammals, 8 metatherians, and 3 monotremes were analyzed with a Bayesian analysis and our site specific rate model. The resultant phylogeny revealed strong support for most nodes and was highly congruent with more recent phylogenies based on nuclear DNA sequences. In addition, many of the conflicting relationships observed by earlier mitochondrial-based analyses were resolved without need for the exclusion of large subsets of the data.Rather than exclusion of data to minimize presumed noise associated with non-protein encoding genes in the mitochondrial genome, our results indicate that selection of an appropriate model that accommodates rate heterogeneity across data partitions and proper treatment of RNA genes can result in a mitochondrial genome-based phylogeny of eutherian mammals that is reasonably congruent with recent phylogenies derived from nuclear genes.The class Mammalia provides a classic example of an adaptive radiation, characterized by a proliferation of lineages displaying a diverse array of ecomorphological specializations for feeding and locomotion [1]. Many additional biological attributes (e.g., behavior, physiology), coupled with this diversity in form and function, have allowed mammals to exploit a broad range of habitats worldwide. There are approximately 135 families of living mammals apportioned into 26 orders and two major subclasses, Prototheria and Theria, with the former subclass containing the order Monotremata (duck-billed platypus and spiny-anteaters) and the latter containing the infraclasses Metatheria (marsupials) and Eutheria (placentals), which are subdivided into 7 and 18 orders, respectively [2,3]. Lineage-specific rate heterogeneity in terms of morphological diversification [4] and molecular divergence [5-7] is a trademark of the various orders and families of mammals, especially within the Eutheria, and this has complicated efforts to resolve phylogenetic relationships among the high
Chronology of Deep Nodes in the Neotropical Primate Phylogeny: Insights from Mitochondrial Genomes  [PDF]
Carlos G. Schrago, Albert N. Menezes, Miguel A. M. Moreira, Alcides Pissinatti, Hector N. Seuánez
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0051699
Abstract: The evolution of Neotropical Primates (NP) is permeated by factors associated with the pattern of diversification and the biogeography of the major lineages. These questions can be better understood by providing a robust estimate of the chronological scenario of NP evolution, a reason why molecular dating methods have been widely applied. One aspect of especial interest is the timing of diversification of the major NP lineages (pitheciids, atelids and cebids), which may have resulted from rapid episodes of adaptive radiation, a question that requires NP divergence time estimates with accurate statistical certainty. In this study, we evaluated the primate timescale focused on the age of nodes of NP radiation. We investigated the performance of complete primate mitochondrial genomes as traditional molecular markers of primate evolution and further including original mitochondrial data from the endangered muriqui, Brachyteles arachnoides (Accession No. JX262672). Comparisons of the age estimates at NP nodes based on mitochondrial genomes with those obtained from a nuclear supermatrix showed similar degrees of uncertainty. Further molecular data and more informative calibration priors are required for a more precise understanding of the early NP diversification.
Genomes-based phylogeny of the genus Xanthomonas
Luis M Rodriguez-R, Alejandro Grajales, Mario L Arrieta-Ortiz, Camilo Salazar, Silvia Restrepo, Adriana Bernal
BMC Microbiology , 2012, DOI: 10.1186/1471-2180-12-43
Abstract: Here we report the results of the genome-wide analysis of DNA sequences from 989 orthologous groups from 17 Xanthomonas spp. genomes available to date, representing all major lineages within the genus. The phylogenetic and computational analyses used in this study have been automated in a Perl package designated Unus, which provides a framework for phylogenomic analyses which can be applied to other datasets at the genomic level. Unus can also be easily incorporated into other phylogenomic pipelines.Our phylogeny agrees with previous phylogenetic topologies on the genus, but revealed that the genomes of Xanthomonas citri and Xanthomonas fuscans belong to the same species, and that of Xanthomonas albilineans is basal to the joint clade of Xanthomonas and Xylella fastidiosa. Genome reduction was identified in the species Xanthomonas vasicola in addition to the previously identified reduction in Xanthomonas albilineans. Lateral gene transfer was also observed in two gene clusters.Xanthomonas is a genus in the gamma division of Proteobacteria primarily constituted by pathogens to plants of considerable economic importance. These pathogens affect a wide variety of crops, including Citrus spp. (lime, orange, lemon and pomelo, among others), Oryza spp. (rice), crucifers (cabbage, broccoli, cauliflower, radish and Arabidopsis thaliana) and Manihot esculenta (cassava), with individual members showing a high degree of host specificity [1]. Xanthomonas is among the few bacterial genera in which large DNA-DNA hybridization, RFLP and REP-PCR datasets are available [2-6] and have been employed for the taxonomical resolution of the group [7]. In addition, the availability of more than ten genomes within the genus [8,9] has allowed recent studies of comparative genomics and genome evolution [10,11].The genus Xanthomonas has been subject to numerous taxonomical and phylogenetic studies, starting with the description of Bacterium vesicatorium as the causal agent of bacterial spot on
The Expanded mtDNA Phylogeny of the Franco-Cantabrian Region Upholds the Pre-Neolithic Genetic Substrate of Basques  [PDF]
Sergio Cardoso, Laura Valverde, Miguel A. Alfonso-Sánchez, Leire Palencia-Madrid, Xabier Elcoroaristizabal, Jaime Algorta, Susana Catarino, David Arteta, Rene J. Herrera, María Teresa Zarrabeitia, José A. Pe?a, Marian M. de Pancorbo
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0067835
Abstract: The European genetic landscape has been shaped by several human migrations occurred since Paleolithic times. The accumulation of archaeological records and the concordance of different lines of genetic evidence during the last two decades have triggered an interesting debate concerning the role of ancient settlers from the Franco-Cantabrian region in the postglacial resettlement of Europe. Among the Franco-Cantabrian populations, Basques are regarded as one of the oldest and more intriguing human groups of Europe. Recent data on complete mitochondrial DNA genomes focused on macrohaplogroup R0 revealed that Basques harbor some autochthonous lineages, suggesting a genetic continuity since pre-Neolithic times. However, excluding haplogroup H, the most representative lineage of macrohaplogroup R0, the majority of maternal lineages of this area remains virtually unexplored, so that further refinement of the mtDNA phylogeny based on analyses at the highest level of resolution is crucial for a better understanding of the European prehistory. We thus explored the maternal ancestry of 548 autochthonous individuals from various Franco-Cantabrian populations and sequenced 76 mitogenomes of the most representative lineages. Interestingly, we identified three mtDNA haplogroups, U5b1f, J1c5c1 and V22, that proved to be representative of Franco-Cantabria, notably of the Basque population. The seclusion and diversity of these female genetic lineages support a local origin in the Franco-Cantabrian area during the Mesolithic of southwestern Europe, ~10,000 years before present (YBP), with signals of expansions at ~3,500 YBP. These findings provide robust evidence of a partial genetic continuity between contemporary autochthonous populations from the Franco-Cantabrian region, specifically the Basques, and Paleolithic/Mesolithic hunter-gatherer groups. Furthermore, our results raise the current proportion (≈15%) of the Franco-Cantabrian maternal gene pool with a putative pre-Neolithic origin to ≈35%, further supporting the notion of a predominant Paleolithic genetic substrate in extant European populations.
Updating Phylogeny of Mitochondrial DNA Macrohaplogroup M in India: Dispersal of Modern Human in South Asian Corridor  [PDF]
Adimoolam Chandrasekar,Satish Kumar,Jwalapuram Sreenath,Bishwa Nath Sarkar,Bhaskar Pralhad Urade,Sujit Mallick,Syam Sundar Bandopadhyay,Pinuma Barua,Subihra Sankar Barik,Debasish Basu,Uttaravalli Kiran,Prodyot Gangopadhyay,Ramesh Sahani,Bhagavatula Venkata Ravi Prasad,Shampa Gangopadhyay,Gandikota Rama Lakshmi,Rajasekhara Reddy Ravuri,Koneru Padmaja,Pulamaghatta N. Venugopal,Madhu Bala Sharma,Vadlamudi Raghavendra Rao
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0007447
Abstract: To construct maternal phylogeny and prehistoric dispersals of modern human being in the Indian sub continent, a diverse subset of 641 complete mitochondrial DNA (mtDNA) genomes belonging to macrohaplogroup M was chosen from a total collection of 2,783 control-region sequences, sampled from 26 selected tribal populations of India. On the basis of complete mtDNA sequencing, we identified 12 new haplogroups - M53 to M64; redefined/ascertained and characterized haplogroups M2, M3, M4, M5, M6, M8′C′Z, M9, M10, M11, M12-G, D, M18, M30, M33, M35, M37, M38, M39, M40, M41, M43, M45 and M49, which were previously described by control and/or coding-region polymorphisms. Our results indicate that the mtDNA lineages reported in the present study (except East Asian lineages M8′C′Z, M9, M10, M11, M12-G, D ) are restricted to Indian region.The deep rooted lineages of macrohaplogroup ‘M’ suggest in-situ origin of these haplogroups in India. Most of these deep rooting lineages are represented by multiple ethnic/linguist groups of India. Hierarchical analysis of molecular variation (AMOVA) shows substantial subdivisions among the tribes of India (Fst = 0.16164). The current Indian mtDNA gene pool was shaped by the initial settlers and was galvanized by minor events of gene flow from the east and west to the restricted zones. Northeast Indian mtDNA pool harbors region specific lineages, other Indian lineages and East Asian lineages. We also suggest the establishment of an East Asian gene in North East India through admixture rather than replacement.
Evolution and phylogeny of the mud shrimps (Crustacea: Decapoda) revealed from complete mitochondrial genomes  [cached]
Lin Feng-Jiau,Liu Yuan,Sha Zhongli,Tsang Ling
BMC Genomics , 2012, DOI: 10.1186/1471-2164-13-631
Abstract: Background The evolutionary history and relationships of the mud shrimps (Crustacea: Decapoda: Gebiidea and Axiidea) are contentious, with previous attempts revealing mixed results. The mud shrimps were once classified in the infraorder Thalassinidea. Recent molecular phylogenetic analyses, however, suggest separation of the group into two individual infraorders, Gebiidea and Axiidea. Mitochondrial (mt) genome sequence and structure can be especially powerful in resolving higher systematic relationships that may offer new insights into the phylogeny of the mud shrimps and the other decapod infraorders, and test the hypothesis of dividing the mud shrimps into two infraorders. Results We present the complete mitochondrial genome sequences of five mud shrimps, Austinogebia edulis, Upogebia major, Thalassina kelanang (Gebiidea), Nihonotrypaea thermophilus and Neaxius glyptocercus (Axiidea). All five genomes encode a standard set of 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a putative control region. Except for T. kelanang, mud shrimp mitochondrial genomes exhibited rearrangements and novel patterns compared to the pancrustacean ground pattern. Each of the two Gebiidea species (A. edulis and U. major) and two Axiidea species (N. glyptocercus and N. thermophiles) share unique gene order specific to their infraorders and analyses further suggest these two derived gene orders have evolved independently. Phylogenetic analyses based on the concatenated nucleotide and amino acid sequences of 13 protein-coding genes indicate the possible polyphyly of mud shrimps, supporting the division of the group into two infraorders. However, the infraordinal relationships among the Gebiidea and Axiidea, and other reptants are poorly resolved. The inclusion of mt genome from more taxa, in particular the reptant infraorders Polychelida and Glypheidea is required in further analysis. Conclusions Phylogenetic analyses on the mt genome sequences and the distinct gene orders provide further evidences for the divergence between the two mud shrimp infraorders, Gebiidea and Axiidea, corroborating previous molecular phylogeny and justifying their infraordinal status. Mitochondrial genome sequences appear to be promising markers for resolving phylogenetic issues concerning decapod crustaceans that warrant further investigations and our present study has also provided further information concerning the mt genome evolution of the Decapoda.
Seven new dolphin mitochondrial genomes and a time-calibrated phylogeny of whales
Ye Xiong, Matthew C Brandley, Shixia Xu, Kaiya Zhou, Guang Yang
BMC Evolutionary Biology , 2009, DOI: 10.1186/1471-2148-9-20
Abstract: The "deep" phylogenetic relationships are well supported including the monophyly of Cetacea and Odontoceti. However, there is ambiguity in the phylogenetic affinities of two of the river dolphin clades Platanistidae (Indian River dolphins) and Lipotidae (Yangtze River dolphins). The phylogenetic analyses support a sister relationship between Delphinidae and Monodontidae + Phocoenidae. Additionally, there is statistically significant support for the paraphyly of Tursiops (bottlenose dolphins) and Stenella (spotted dolphins).Our phylogenetic analysis of complete mitochondrial genomes using recently developed models of rate autocorrelation resolved the phylogenetic relationships of the major Cetacean lineages with a high degree of confidence. Our results indicate that a rapid radiation of lineages explains the lack of support the placement of Platanistidae and Lipotidae. Moreover, our estimation of molecular divergence dates indicates that these radiations occurred in the Middle to Late Oligocene and Middle Miocene, respectively. Furthermore, by collecting and analyzing seven new mitochondrial genomes, we provide strong evidence that the delphinid genera Tursiops and Stenella are not monophyletic, and the current taxonomy masks potentially interesting patterns of morphological, physiological, behavioral, and ecological evolution.Cetaceans (whales, dolphins, and porpoises) have been the subjects of intense phylogenetic inquiry using both morphological (including fossil) and molecular data [1-19]. This attention is not surprising; Cetaceans represent one of the most fascinating evolutionary transitions within vertebrates and a robust phylogenetic framework is the underpinning of any study into morphological, behavioral, and physiological evolution. The results of these phylogenetic inquiries agree on several key relationships including the monophyly of Cetacea and Mysticeti (baleen whales), and the close relationships of the Amazon (Iniidae) and La Plata (Pontoporidae) R
Mitochondrial Genomes of Two Barklice, Psococerastis albimaculata and Longivalvus hyalospilus (Psocoptera: Psocomorpha): Contrasting Rates in Mitochondrial Gene Rearrangement between Major Lineages of Psocodea  [PDF]
Hu Li, Renfu Shao, Fan Song, Xuguo Zhou, Qianqian Yang, Zhihong Li, Wanzhi Cai
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0061685
Abstract: The superorder Psocodea has ~10,000 described species in two orders: Psocoptera (barklice and booklice) and Phthiraptera (parasitic lice). One booklouse, Liposcelis bostrychophila and six species of parasitic lice have been sequenced for complete mitochondrial (mt) genomes; these seven species have the most rearranged mt genomes seen in insects. The mt genome of a barklouse, lepidopsocid sp., has also been sequenced and is much less rearranged than those of the booklouse and the parasitic lice. To further understand mt gene rearrangements in the Psocodea, we sequenced the mt genomes of two barklice, Psococerastis albimaculata and Longivalvus hyalospilus, the first representatives from the suborder Psocomorpha, which is the most species-rich suborder of the Psocodea. We found that these two barklice have the least rearranged mt genomes seen in the Psocodea to date: a protein-coding gene (nad3) and five tRNAs (trnN, trnS1, trnE, trnM and trnC) have translocated. Rearrangements of mt genes in these two barklice can be accounted for by two events of tandem duplication followed by random deletions. Phylogenetic analyses of the mt genome sequences support the view that Psocoptera is paraphyletic whereas Phthiraptera is monophyletic. The booklouse, L. bostrychophila (suborder Troctomorpha) is most closely related to the parasitic lice. The barklice (suborders Trogiomorpha and Psocomorpha) are closely related and form a monophyletic group. We conclude that mt gene rearrangement has been substantially faster in the lineage leading to the booklice and the parasitic lice than in the lineage leading to the barklice. Lifestyle change appears to be associated with the contrasting rates in mt gene rearrangements between the two lineages of the Psocodea.
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