Large-scale mitochondrial gene rearrangements in the hermit crab Pagurus nigrofascia and phylogenetic analysis of the Anomura

Gene ◽  
2019 ◽  
Vol 695 ◽  
pp. 75-83 ◽  
Author(s):  
Li Gong ◽  
Hui Jiang ◽  
Kehua Zhu ◽  
Xinting Lu ◽  
Liqin Liu ◽  
...  
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Xu Wang ◽  
Lihua Jia ◽  
Mingdao Wang ◽  
Hao Yang ◽  
Mingyue Chen ◽  
...  

Abstract Taiwanofungus camphoratus is a highly valued medicinal mushroom that is endemic to Taiwan, China. In the present study, the mitogenome of T. camphoratus was assembled and compared with other published Polyporales mitogenomes. The T. camphoratus mitogenome was composed of circular DNA molecules, with a total size of 114,922 bp. Genome collinearity analysis revealed large-scale gene rearrangements between the mitogenomes of Polyporales, and T. camphoratus contained a unique gene order. The number and classes of introns were highly variable in 12 Polyporales species we examined, which proved that numerous intron loss or gain events occurred in the evolution of Polyporales. The Ka/Ks values for most core protein coding genes in Polyporales species were less than 1, indicating that these genes were subject to purifying selection. However, the rps3 gene was found under positive or relaxed selection between some Polyporales species. Phylogenetic analysis based on the combined mitochondrial gene set obtained a well-supported topology, and T. camphoratus was identified as a sister species to Laetiporus sulphureus. This study served as the first report on the mitogenome in the Taiwanofungus genus, which will provide a basis for understanding the phylogeny and evolution of this important fungus.


2019 ◽  
Author(s):  
Li Gong ◽  
Xinting Lu ◽  
Zhifu Wang ◽  
Wei Shi ◽  
Kehua Zhu ◽  
...  

Abstract Background: Gene arrangement in vertebrate mitochondrial genomes (mitogenomes) is relatively conserved and fewer gene arrangement is discovered. In contrast, that in invertebrate mitogenomes is relatively common. Although a gradually growing number of gene rearrangement in hermit crabs (Paguridae) has been discovered, it is surprising that gene rearrangement in its close relatives, the terrestrial hermit crab (Coenobitidae), was overlooked until 2018. So far, only few studies focused on the phylogenetic studies of Anomura based on molecular evidences. Results: In the present study, the complete mitogenome of a terrestrial hermit crab, Coenobita brevimanus, was sequenced, and large-scale gene rearrangements were observed. The genomic features of this terrestrial hermit crab were different from those of any other studied crabs. Five gene clusters (or genes) including eleven tRNAs and two PCGs were found to be rearranged with respect to the pancrustacean ground pattern gene order, which was characterized by multiple translocations and inversions. Two phylogenetic trees (ML and BI tree) arrived at a similar topology based on the nucleotide sequences of the 13 concatenated PCGs. Conclusions: We propose tandem duplication-random loss and recombination model to explain the large-scale gene rearrangements in C. brevimanus mitogenome. The phylogenetic trees showed that all Coenobitidae species clustered into one clade. The polyphyly of Paguroidea was well supported, whereas the non-monophyly of Galatheoidea was not in consistence with previous findings. The phylogenetic relationships of Pylochelidae, Lomidae, and Albuneidae were controversial.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Cheng Chen ◽  
Qiang Li ◽  
Rongtao Fu ◽  
Jian Wang ◽  
Guangmin Deng ◽  
...  

AbstractTrametes species are efficient wood decomposers that are widespread throughout the world. Mitogenomes have been widely used to understand the phylogeny and evolution of fungi. Up to now, two mitogenomes from the Trametes genus have been revealed. In the present study, the complete mitogenomes of two novel Trametes species, Trametes versicolor and T. coccinea, were assembled and compared with other Polyporales mitogenomes. Both species contained circular DNA molecules, with sizes of 67,318 bp and 99,976 bp, respectively. Comparative mitogenomic analysis indicated that the gene number, length and base composition varied between the four Trametes mitogenomes we tested. In addition, all of the core protein coding genes in Trametes species were identified and subjected to purifying selection. The mitogenome of T. coccinea contained the largest number of introns among the four Trametes species tested, and introns were considered the main factors contributing to size variations of Polyporales. Several novel introns were detected in the Trametes species we assembled, and introns identified in Polyporales were found to undergo frequent loss/gain events. Large-scale gene rearrangements were detected between closely related Trametes species, including gene inversions, insertions, and migrations. A well-supported phylogenetic tree for 77 Basidiomycetes was obtained based on the combined mitochondrial gene set using 2 phylogenetic inference methods. The results showed that mitochondrial genes are effective molecular markers for understanding the phylogeny of Basidiomycetes. This study is the first to report the mitogenome rearrangement and intron dynamics of Trametes species, which shed light on the evolution of Trametes and other related species.


2006 ◽  
Vol 37 (4) ◽  
pp. 467-479 ◽  
Author(s):  
Gregor Kölsch ◽  
Bo Vest Pedersen ◽  
Olof Biström

AbstractThe genus Macroplea Samouelle, 1819 is a group of highly specialized aquatic leaf beetles occurring in the Palaearctic. Since the members of this genus are morphologically very similar, we addressed the question of species identification and delimitation by analysing the second half of the mitochondrial gene coding for the cytochrome oxidase I (COI) subunit. Species limits are inferred from the multimodal frequency distribution of genetic distances between specimens: low genetic distances within a species are clearly set apart from distances between species. The species status of the hitherto controversial species M. japana (Jacoby, 1885) is confirmed. The pattern of nucleotide and amino acid substitutions is discussed in the light of functional domains of the COI molecule. Although the data are preliminary, the results provide new data on the distribution of the species. Together with the phylogenetic analysis they allow for a discussion of the phylogeography of the genus.


2018 ◽  
Vol 93 (1) ◽  
pp. 137-156 ◽  
Author(s):  
Rainer R. Schoch

AbstractDissorophoid temnospondyls are widely considered to have given rise to some or all modern amphibians (Lissamphibia), but their ingroup relationships still bear major unresolved questions. An inclusive phylogenetic analysis of dissorophoids gives new insights into the large-scale topology of relationships. Based on a TNT 1.5 analysis (33 taxa, 108 characters), the enigmatic taxonPerryellais found to nest just outside Dissorophoidea (phylogenetic defintion), but shares a range of synapomorphies with this clade. The dissorophoids proper are found to encompass a first dichotomy between the largely paedomorphic Micromelerpetidae and all other taxa (Xerodromes). Within the latter, there is a basal dichotomy between the large, heavily ossified Olsoniformes (Dissorophidae + Trematopidae) and the small salamander-like Amphibamiformes (new taxon), which include four clades: (1) Micropholidae (Tersomius,Pasawioops,Micropholis); (2) Amphibamidae sensu stricto (Doleserpeton,Amphibamus); (3) Branchiosauridae (Branchiosaurus,Apateon,Leptorophus,Schoenfelderpeton); and (4) Lissamphibia. The generaPlatyrhinopsandEoscopusare here found to nest at the base of Amphibamiformes. Represented by their basal-most stem-taxa (Triadobatrachus,Karaurus,Eocaecilia), lissamphibians nest withGerobatrachusrather than Amphibamidae, as repeatedly found by former analyses.UUID:http://zoobank.org/dadf36db-e003-4af7-bfa7-44d79bc04450


Author(s):  
Emanuel TSCHOPP ◽  
Paul UPCHURCH

ABSTRACTSpecimen-level phylogenetic approaches are widely used in molecular biology for taxonomic and systematic purposes. However, they have been largely ignored in analyses based on morphological traits, where phylogeneticists mostly resort to species-level analyses. Recently, a number of specimen-level studies have been published in vertebrate palaeontology. These studies indicate that specimen-level phylogeny may be a very useful tool for systematic reassessments at low taxonomic levels. Herein, we review the challenges when working with individual organisms as operational taxonomic units in a palaeontological context, and propose guidelines of how best to perform a specimen-level phylogenetic analysis using the maximum parsimony criterion. Given that no single methodology appears to be perfectly suited to resolve relationships among individuals, and that different taxa probably require different approaches to assess their systematics, we advocate the use of a number of methodologies. In particular, we recommend the inclusion of as many specimens and characters as feasible, and the analysis of relationships using an extended implied weighting approach with different downweighting functions. Resulting polytomies should be explored using a posteriori pruning of unstable specimens, and conflicting tree topologies between different iterations of the analysis should be evaluated by a combination of support values such as jackknifing and symmetric resampling. Species delimitation should be consistent among the ingroup and based on a reproducible approach. Although time-consuming and methodologically challenging, specimen-level phylogenetic analysis is a highly useful tool to assess intraspecific variability and provide the basis for a more informed and accurate creation of species-level operational taxonomic units in large-scale systematic studies. It also has the potential to inform us about past speciation processes, morphological trait evolution, and their potential intrinsic and extrinsic drivers in pre-eminent detail.


ZooKeys ◽  
2020 ◽  
Vol 954 ◽  
pp. 1-15
Author(s):  
Weixin Liu ◽  
Sergei Golovatch

A new species of glomeridellid millipede is described from Guizhou Province, southern China: Tonkinomeris huzhengkunisp. nov. This new epigean species differs very clearly in many structural details, being sufficiently distinct morphologically and disjunct geographically from T. napoensis Nguyen, Sierwald & Marek, 2019, the type and sole species of Tonkinomeris Nguyen, Sierwald & Marek, 2019, which was described recently from northern Vietnam. The genus Tonkinomeris is formally relegated from Glomeridae and assigned to the family Glomeridellidae, which has hitherto been considered strictly Euro-Mediterranean in distribution and is thus new to the diplopod faunas of China and Indochina. Tonkinomeris is re-diagnosed and shown to have perhaps the basalmost position in the family Glomeridellidae. Its relationships are discussed, both morphological and zoogeographical, within and outside the Glomeridellidae, which can now be considered as relict and basically Oriental in origin. Because of the still highly limited array of DNA-barcoding sequences of the COI mitochondrial gene available in the GenBank, the first molecular phylogenetic analysis of Glomerida attempted here shows our phylogram to be too deficient to consider meaningful.


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