scholarly journals New Non-Bilaterian Transcriptomes Provide Novel Insights into the Evolution of Coral Skeletomes

2019 ◽  
Vol 11 (11) ◽  
pp. 3068-3081 ◽  
Author(s):  
Nicola Conci ◽  
Gert Wörheide ◽  
Sergio Vargas

Abstract A general trend observed in animal skeletomes—the proteins occluded in animal skeletons—is the copresence of taxonomically widespread and lineage-specific proteins that actively regulate the biomineralization process. Among cnidarians, the skeletomes of scleractinian corals have been shown to follow this trend. However, distributions and phylogenetic analyses of biomineralization-related genes are often based on only a few species, with other anthozoan calcifiers such as octocorals (soft corals), not being fully considered. We de novo assembled the transcriptomes of four soft-coral species characterized by different calcification strategies (aragonite skeleton vs. calcitic sclerites) and data-mined published nonbilaterian transcriptome resources to construct a taxonomically comprehensive sequence database to map the distribution of scleractinian and octocoral skeletome components. Cnidaria shared no skeletome proteins with Placozoa or Ctenophora, but did share some skeletome proteins with Porifera, such as galaxin-related proteins. Within Scleractinia and Octocorallia, we expanded the distribution for several taxonomically restricted genes such as secreted acidic proteins, scleritin, and carbonic anhydrases, and propose an early, single biomineralization-recruitment event for galaxin sensu stricto. Additionally, we show that the enrichment of acidic residues within skeletogenic proteins did not occur at the Corallimorpharia–Scleractinia transition, but appears to be associated with protein secretion into the organic matrix. Finally, the distribution of octocoral calcification-related proteins appears independent of skeleton mineralogy (i.e., aragonite/calcite) with no differences in the proportion of shared skeletogenic proteins between scleractinians and aragonitic or calcitic octocorals. This points to skeletome homogeneity within but not between groups of calcifying cnidarians, although some proteins such as galaxins and SCRiP-3a could represent instances of commonality.

2019 ◽  
Author(s):  
Nicola Conci ◽  
Gert Wörheide ◽  
Sergio Vargas

AbstractA general feature of animal skeletomes is the co-presence of taxonomically widespread and lineage-specific proteins that actively regulate the biomineralization process. Among cnidarians, the skeletomes of scleractinian corals have been shown to follow this trend, however in this group distribution and phylogenetic analyses of biomineralization-related genes have been often based on limited numbers of species, with other anthozoan calcifiers such as octocorals, being overlooked. We de-novo sequenced the transcriptomes of four soft-coral species characterized by different calcification strategies (aragonite skeleton vs. calcitic sclerites) and data-mined published non-bilaterian transcriptomic resources to construct a taxonomically comprehensive sequence database to map the distribution of scleractinian and octocoral skeletome components. At the large scale, no protein showed a ‘Cnidaria+Placozoa’ or ‘Cnidaria+Ctenophora’ distribution, while some were found in cnidarians and Porifera. Within Scleractinia and Octocorallia, we expanded the distribution for several taxonomically restricted genes (TRGs) and propose an alternative evolutionary scenario, involving an early single biomineralization-recruitment event, for galaxin sensu stricto. Additionally, we show that the enrichment of acidic residues within skeletogenic proteins did not occur at the Corallimorpharia-Scleractinia transition, but appears to be associated with protein secretion in the organic matrix. Finally, the distribution of octocoral calcification-related proteins appears independent of skeleton mineralogy (i.e. aragonite/calcite) with no differences on the proportion of shared skeletogenic proteins between scleractinians and aragonitic or calcitic octocorals. This points to skeletome homogeneity within but not between groups of calcifying cnidarians, although some proteins like galaxins and SCRiP-3a could represent instances of commonality.


Botany ◽  
2016 ◽  
Vol 94 (10) ◽  
pp. 917-939 ◽  
Author(s):  
Amanda M. Savoie ◽  
Gary W. Saunders

Sequence data (COI-5P and rbcL) for North American members of the tribe Pterosiphonieae were compared with collections from around the world. Phylogenetic analyses resolved Pterosiphonia as polyphyletic and many species required transfer to other genera. In our analyses Pterosiphonia sensu stricto included only the type species P. cloiophylla (C. Agardh) Falkenberg and P. complanata (Clemente) Falkenberg, as well as the South African species P. stegengae sp. nov. A new genus, Xiphosiphonia gen. nov., was described for X. ardreana (Maggs & Hommersand) comb. nov., X. pennata (C. Agardh) comb. nov., and X. pinnulata (Kützing) comb. nov. Some Asian, European and North American species previously attributed to Pterosiphonia were transferred to Symphyocladia including S. baileyi (Harvey) comb. nov., S. dendroidea (Montagne) comb. nov., S. plumosa nom. nov. (for P. gracilis Kylin), and S. tanakae (S. Uwai & M. Masuda) comb. nov. We also described two new North American species, Symphyocladia brevicaulis sp. nov. and S. rosea sp. nov. Other species formed a well-supported clade for which the genus name Polyostea Ruprecht was resurrected. Included in Polyostea were P. arctica (J. Agardh) comb. nov., P. bipinnata (Postels & Ruprecht) Ruprecht, P. hamata (E.S. Sinova) comb. nov., and P. robusta (N.L. Gardner) comb. nov.


2017 ◽  
Author(s):  
Meng Wu ◽  
Jamie L. Kostyun ◽  
Matthew W. Hahn ◽  
Leonie Moyle

ABSTRACTPhylogenetic analyses of trait evolution can provide insight into the evolutionary processes that initiate and drive phenotypic diversification. However, recent phylogenomic studies have revealed extensive gene tree-species tree discordance, which can lead to incorrect inferences of trait evolution if only a single species tree is used for analysis. This phenomenon—dubbed “hemiplasy”—is particularly important to consider during analyses of character evolution in rapidly radiating groups, where discordance is widespread. Here we generate whole-transcriptome data for a phylogenetic analysis of 14 species in the plant genus Jaltomata (the sister clade to Solanum), which has experienced rapid, recent trait evolution, including in fruit and nectar color, and flower size and shape. Consistent with other radiations, we find evidence for rampant gene tree discordance due to incomplete lineage sorting (ILS) and several introgression events among the well-supported subclades. Since both ILS and introgression increase the probability of hemiplasy, we perform several analyses that take discordance into account while identifying genes that might contribute to phenotypic evolution. Despite discordance, the history of fruit color evolution in Jaltomata can be inferred with high confidence, and we find evidence of de novo adaptive evolution at individual genes associated with fruit color variation. In contrast, hemiplasy appears to strongly affect inferences about floral character transitions in Jaltomata, and we identify candidate loci that could arise either from multiple lineage-specific substitutions or standing ancestral polymorphisms. Our analysis provides a generalizable example of how to manage discordance when identifying loci associated with trait evolution in a radiating lineage.


2021 ◽  
Vol 9 ◽  
Author(s):  
Jeana L. Drake ◽  
Maxence Guillermic ◽  
Robert A. Eagle ◽  
David K. Jacobs

Scleractinian corals typically form a robust calcium carbonate skeleton beneath their living tissue. This skeleton, through its trace element composition and isotope ratios, may record environmental conditions of water surrounding the coral animal. While bulk unrecrystallized aragonite coral skeletons can be used to reconstruct past ocean conditions, corals that have undergone significant diagenesis have altered geochemical signatures and are typically assumed to retain insufficient meaningful information for bulk or macrostructural analysis. However, partially recrystallized skeletons may retain organic molecular components of the skeletal organic matrix (SOM), which is secreted by the animal and directs aspects of the biomineralization process. Some SOM proteins can be retained in fossil corals and can potentially provide past oceanographic, ecological, and indirect genetic information. Here, we describe a dataset of scleractinian coral skeletons, aged from modern to Cretaceous plus a Carboniferous rugosan, characterized for their crystallography, trace element composition, and amino acid compositions. We show that some specimens that are partially recrystallized to calcite yield potentially useful biochemical information whereas complete recrystalization or silicification leads to significant alteration or loss of the SOM fraction. Our analysis is informative to biochemical-paleoceanographers as it suggests that previously discounted partially recrystallized coral skeletons may indeed still be useful at the microstructural level.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10364
Author(s):  
Natalia I. Abramson ◽  
Fedor N. Golenishchev ◽  
Semen Yu. Bodrov ◽  
Olga V. Bondareva ◽  
Evgeny A. Genelt-Yanovskiy ◽  
...  

In this article, we present the nearly complete mitochondrial genome of the Subalpine Kashmir vole Hyperacrius fertilis (Arvicolinae, Cricetidae, Rodentia), assembled using data from Illumina next-generation sequencing (NGS) of the DNA from a century-old museum specimen. De novo assembly consisted of 16,341 bp and included all mitogenome protein-coding genes as well as 12S and 16S RNAs, tRNAs and D-loop. Using the alignment of protein-coding genes of 14 previously published Arvicolini tribe mitogenomes, seven Clethrionomyini mitogenomes, and also Ondatra and Dicrostonyx outgroups, we conducted phylogenetic reconstructions based on a dataset of 13 protein-coding genes (PCGs) under maximum likelihood and Bayesian inference. Phylogenetic analyses robustly supported the phylogenetic position of this species within the tribe Arvicolini. Among the Arvicolini, Hyperacrius represents one of the early-diverged lineages. This result of phylogenetic analysis altered the conventional view on phylogenetic relatedness between Hyperacrius and Alticola and prompted the revision of morphological characters underlying the former assumption. Morphological analysis performed here confirmed molecular data and provided additional evidence for taxonomic replacement of the genus Hyperacrius from the tribe Clethrionomyini to the tribe Arvicolini.


Phytotaxa ◽  
2021 ◽  
Vol 500 (1) ◽  
pp. 1-10
Author(s):  
MENG-LE XIE ◽  
TIE-ZHENG WEI ◽  
BÁLINT DIMA ◽  
YONG-PING FU ◽  
RUI-QING JI ◽  
...  

This study presents one telamonioid species new to science based on morphological characteristics and molecular phylogenetic analyses. Cortinarius khinganensis was collected from the Greater Khingan Mountains, Northeast China and it is characterized by hygrophanous, vivid brownish red and striate pileus, white universal veil, and subglobose spores. According to phylogenetic analyses results, C. khinganensis belongs to the section Illumini, which is a lineage distantly related from subgenus Telamonia sensu stricto. Detailed descriptions of the new species and the comparisons with morphologically similar species are provided. The phylogenetic relationships within the section Illumini are also discussed.


2019 ◽  
Vol 94 ◽  
Author(s):  
A. Santacruz ◽  
C.P. Ornelas-García ◽  
G. Pérez-Ponce de León

AbstractAmong fish parasitic nematodesRhabdochonais one of the most speciose genera, withc.100 species. Twelve congeneric species occur in Mexican freshwater fishes, in a region located between the Nearctic and Neotropical biogeographical regions. Host association and biogeographical history have determined the high species richness ofRhabdochonain Mexico. One of these species,Rhabdochona mexicana, is highly specific to the characid genusAstyanax.Characids are a group of freshwater fish with Neotropical affinity. In this paper, we explore the genetic diversity ofR. mexicanathrough samples obtained from populations ofAstyanaxspp. across river basins of Mexico and Guatemala. Sequences of one mitochondrial and two ribosomal genes were obtained from 38 individuals and analysed using Maximum Likelihood and Bayesian Inference analysis. Phylogenetic analyses usingcox1, and a concatenated alignment of 18S + 28S +cox1 recovered two genetic lineages. One of them corresponded withR. mexicana sensu stricto; this lineage included three reciprocally monophyletic subgroups; the other lineage was highly divergent and represented a putative candidate species. A detailed morphological study was conducted to corroborate the molecular findings. We describe a new species herein and discuss the implications of using molecular tools to increase our knowledge about the diversity of a speciose genus such asRhabdochona.


2020 ◽  
Vol 86 (6) ◽  
Author(s):  
Ebrahim Osdaghi ◽  
Touraj Rahimi ◽  
S. Mohsen Taghavi ◽  
Maryam Ansari ◽  
Sadegh Zarei ◽  
...  

ABSTRACT Members of the genus Clavibacter are economically important bacterial plant pathogens infecting a set of diverse agricultural crops (e.g., alfalfa, corn, potato, tomato, and wheat). Tomato-associated Clavibacter sp. strains account for a great portion of the genetic diversity of the genus, and C. michiganensis sensu stricto (formerly C. michiganensis subsp. michiganensis), causing bacterial canker disease, is considered one of the most destructive seed-borne agents for the crop worldwide. However, current taxonomic descriptions of the genus do not reflect the existing diversity of the strains, resulting in unsatisfactory results in quarantine surveys for the pathogens. In this study, we used all the available genome sequences of Clavibacter sp. strains, including the type strains of newly described subspecies, to provide precise insight into the diversity of tomato-associated members of the genus and further clarify the taxonomic status of the strains using genotypic and phenotypic features. The results of phylogenetic analyses revealed the existence of nine hypothetical new species among the investigated strains. None of the three new subspecies (i.e., C. michiganensis subsp. californiensis, C. michiganensis subsp. chilensis, and C. michiganensis subsp. phaseoli) is included within the tomato-pathogenic C. michiganensis sensu stricto lineage. Although comparative genomics revealed the lack of chp and tomA pathogenicity determinant gene clusters in the nonpathogenic strains, a number of pathogenicity-related genes were noted to be present in all the strains regardless of their pathogenicity characteristics. Altogether, our results indicate a need for a formal taxonomic reconsideration of tomato-associated Clavibacter sp. strains to facilitate differentiation of the lineages in quarantine inspections. IMPORTANCE Clavibacter spp. are economically important bacterial plant pathogens infecting a set of diverse agricultural crops, such as alfalfa, corn, pepper, potato, tomato, and wheat. A number of plant-pathogenic members of the genus (e.g., C. michiganensis sensu stricto and C. sepedonicus, infecting tomato and potato plants, respectively) are included in the A2 (high-risk) list of quarantine pathogens by the European and Mediterranean Plant Protection Organization (EPPO). Although tomato-associated members of Clavibacter spp. account for a significant portion of the genetic diversity in the genus, only the strains belonging to C. michiganensis sensu stricto (formerly C. michiganensis subsp. michiganensis) cause bacterial canker disease of tomato and are subjected to the quarantine inspections. Hence, discrimination between the pathogenic and nonpathogenic Clavibacter sp. strains associated with tomato seeds and transplants plays a pivotal role in the accurate detection and cost-efficient management of the disease. On the other hand, detailed information on the genetic contents of different lineages of the genus would lead to the development of genome-informed specific detection techniques. In this study, we have provided an overview of the phylogenetic and genomic differences between the pathogenic and nonpathogenic tomato-associated Clavibacter sp. strains. We also noted that the taxonomic status of newly introduced subspecies of C. michiganensis (i.e., C. michiganensis subsp. californiensis, C. michiganensis subsp. chilensis, and C. michiganensis subsp. phaseoli) should be reconsidered.


Genes ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 321 ◽  
Author(s):  
Serena Cavallero ◽  
Fabrizio Lombardo ◽  
Marco Salvemini ◽  
Antonella Pizzarelli ◽  
Cinzia Cantacessi ◽  
...  

Ascaridoid nematodes are widespread in marine fishes. Despite their major socioeconomic importance, mechanisms associated to the fish-borne zoonotic disease anisakiasis are still obscure. RNA-Seq and de-novo assembly were herein applied to RNA extracted from larvae and dissected pharynx of Hysterothylacium aduncum (HA), a non-pathogenic nematode. Assembled transcripts in HA were annotated and compared to the transcriptomes of the zoonotic species Anisakis simplex sensu stricto (AS) and Anisakis pegreffii (AP). Approximately 60,000,000 single-end reads were generated for HA, AS and AP. Transcripts in HA encoded for 30,254 putative peptides while AS and AP encoded for 20,574 and 20,840 putative peptides, respectively. Differential gene expression analyses yielded 471, 612 and 526 transcripts up regulated in the pharynx of HA, AS and AP. The transcriptomes of larvae and pharynx of HA were enriched in transcripts encoding collagen, peptidases, ribosomal proteins and in heat-shock motifs. Transcripts encoding proteolytic enzymes, anesthetics, inhibitors of primary hemostasis and virulence factors, anticoagulants and immunomodulatory peptides were up-regulated in AS and AP pharynx. This study represents the first transcriptomic characterization of a marine parasitic nematode commonly recovered in fish and probably of negligible concern for public health.


2004 ◽  
Vol 135 (3) ◽  
pp. 1654-1665 ◽  
Author(s):  
Dale T. Karlson ◽  
(Jenny) Qiu-Yun Xiang ◽  
Vicki E. Stirm ◽  
A.M. Shirazi ◽  
Edward N. Ashworth

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