scholarly journals Analysis of major sperm proteins in two nematode species from two classes, Enoplus brevis (Enoplea, Enoplida) and Panagrellus redivivus (Chromadorea, Rhabditida), reveal similar localization, but less homology of protein sequences than expected for Nematoda phylum

2021 ◽  
Author(s):  
Julia K. Zograf ◽  
Yulia A. Trebukhova ◽  
Vladimir V. Yushin ◽  
Konstantin V. Yakovlev
Keyword(s):  
Protein Sequences ◽  
Nematode Species ◽  
Evolutionary Relationships ◽  
Specific System ◽  
Sperm Activation ◽  
Major Clade ◽  
Sperm Proteins ◽  
Panagrellus Redivivus ◽  
Major Sperm Proteins ◽  
Sperm Movement

Abstract Major sperm proteins (MSP) are a nematode-specific system of motor proteins required for amoeboid sperm movement. A number of MSP genes vary in different nematode species, but encoded protein sequences reveal high homology between these proteins. In fact, all studies of MSPs localization and functions are based exclusively on the representatives of the order Rhabditida belonging to the nematode class Chromadorea, while MSP-driven sperm movement in Enoplea, another major clade of the phylum Nematoda is still unconfirmed. In this study, we found out the presence of MSPs in the enoplean nematode Enoplus brevis (Enoplida) and compared MSP localization in sperm of this species with the chromadorean nematode Panagrellus redivivus (Rhabditida). Then, we analyzed the putative MSP sequences of both species. Our results indicate that MSPs are presented in E. brevis spermatozoa and form filamentous structures after sperm activation, which may be considered as the evidence of their motor functions similar to those in the spermatozoa of chromadorean nematodes. We found that E. brevis MSPs show lower homology to known proteins of rhabditids which species reveal hyper-conservatism in MSP protein sequences. It reflects evidently more distant evolutionary relationships of Enoplea and Chromadorea than exist within Rhabditida order. Our data denote necessity of reconsideration of view on MSP evolution within Nematoda.

The demise of the Platonic worm

Nematology ◽  
2000 ◽  
Vol 2 (1) ◽  
pp. 71-79 ◽  
Author(s):  
Armand Leroi ◽  
Scott Emmons ◽  
Ana Cunha ◽  
Ricardo B.R. Azevedo
Keyword(s):  
Caenorhabditis Elegans ◽  
Nematode Species ◽  
Cell Number ◽  
Cell Lineages ◽  
Panagrellus Redivivus ◽  
Seam Cell ◽  
Nous Montrons ◽  
Adult Cell ◽  
Free Living Nematode ◽  
Nuclear Number

AbstractNematodes are generally considered to have an adult cell number that does not vary among wildtype individuals as a consequence of invariant cell lineages (eutely). However, there is extensive evidence that at least some cell lineages can be variable in nematodes. In a comparative study of 13 free-living nematode species, we have shown that the adult epidermis of most species contained variable numbers of nuclei and that this variance was positively correlated with mean epidermal nuclear number. Here we present simulations of the lateral seam cell lineages of four species and show that variance in cell number is influenced by lineage topology, as well as by the frequency of lineage variants. We show that the epidermal variability of Panagrellus redivivus cannot be accounted for by the complexity of its lineage, but requires higher levels of lineage variability than are found in Caenorhabditis elegans, Oscheius myriophila and Rhabditella octopleura. Our findings suggest that many nematodes may have tissues composed of indeterminate numbers of cells formed from variable lineages and, as such, resemble other metazoans. Les nématodes sont généralement considérés comme ayant un nombre de cellules invariable chez les individus de type sauvage, conséquence d’un lignage cellulaire fixe (eutélie). Cependant, il est d’évidence qu’au moins certains des lignages cellulaires peuvent varier chez les nématodes. Dans une étude comparative portant sur 13 espèces de nématodes libres, nous avions montré que l’épiderme de la plupart de ces espèces comportait un nombre variable de noyaux et que cette variabilité était corrélée positivement avec le nombre de noyaux épidermiques. Nous présentons ici des simulations des lignages cellulaires de la suture latérale de quatre espèces et démontrons que le nombre de cellules est influencé tant par la topologie du lignage que par la fréquence des variants de ce lignage. Nous montrons que la variabilité de l’épiderme de Panagrellus redivivus ne peut être mise au compte de la complexité de son lignage, mais demande des niveaux élevés de variabilité de ce lignage, tels ceux trouvés chez Caenorhabditis elegans, Oscheius myriophila et Rhabditella octopleura. Nos observations suggèrent que nombre de nématodes possèdent des tissus composés d’un nombre indéterminé de cellules dérivant de lignages variables et, de ce fait, ressemblent aux autres metazoaires.

scholarly journals The early catfish catches the worm: predation of Corydoras aeneus (Siluriformes, Callichthyidae) on freshwater nematodes

2018 ◽  
Vol 54 ◽  
pp. 29 ◽  
Author(s):  
Nabil Majdi ◽  
Sebastian Weber ◽  
Walter Traunspurger
Keyword(s):  
Nematode Species ◽  
Ornamental Fish ◽  
Live Food ◽  
Daily Consumption ◽  
Freshwater Catfish ◽  
Freshwater Nematodes ◽  
Panagrellus Redivivus ◽  
Wet Weight

In this study, we measured the daily consumption of four different nematode species by a small freshwater catfish species, Corydoras aeneus (Gill, 1858). Consumption of nematodes by fishes was significant with a single C. aeneus individual being able to consume in 24 h between 40 581 and 75 849 adult nematodes depending on the nematode species offered. This represented the ingestion of up to 238 mg wet weight when considering the largest nematode species: Panagrellus redivivus. Our results strengthen the growing evidence of a significant trophic channel existing between meiobenthic invertebrates like nematodes and small bottom-feeding fishes like C. aeneus. We also discuss the relevance of using P. redivivus as live food for rearing C. aeneus which is a popular ornamental fish.

scholarly journals Novel Molecular Synapomorphies Demarcate Different Main Groups/Subgroups of Plasmodium and Piroplasmida Species Clarifying Their Evolutionary Relationships

Genes ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 490 ◽  
Author(s):  
Sharma ◽  
Gupta
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Trees ◽  
Plasmodium Species ◽  
Protein Sequences ◽  
Evolutionary Relationships ◽  
Major Life ◽  
Comparative Analyses ◽  
Large Numbers ◽  
Conserved Signature Indels ◽  
Relationship Of

The class Hematozoa encompasses several clinically important genera, including Plasmodium, whose members cause the major life-threating disease malaria. Hence, a good understanding of the interrelationships of organisms from this class and reliable means for distinguishing them are of much importance. This study reports comprehensive phylogenetic and comparative analyses on protein sequences on the genomes of 28 hematozoa species to understand their interrelationships. In addition to phylogenetic trees based on two large datasets of protein sequences, detailed comparative analyses were carried out on the genomes of hematozoa species to identify novel molecular synapomorphies consisting of conserved signature indels (CSIs) in protein sequences. These studies have identified 79 CSIs that are exclusively present in specific groups of Hematozoa/Plasmodium species, also supported by phylogenetic analysis, providing reliable means for the identification of these species groups and understanding their interrelationships. Of these CSIs, six CSIs are specifically shared by all hematozoa species, two CSIs serve to distinguish members of the order Piroplasmida, five CSIs are uniquely found in all Piroplasmida species except B. microti and two CSIs are specific for the genus Theileria. Additionally, we also describe 23 CSIs that are exclusively present in all genome-sequenced Plasmodium species and two, nine, ten and eight CSIs which are specific for members of the Plasmodium subgenera Haemamoeba, Laverania, Vinckeia and Plasmodium (excluding P. ovale and P. malariae), respectively. Additionally, our work has identified several CSIs that support species relationships which are not evident from phylogenetic analysis. Of these CSIs, one CSI supports the ancestral nature of the avian-Plasmodium species in comparison to the mammalian-infecting groups of Plasmodium species, four CSIs strongly support a specific relationship of species between the subgenera Plasmodium and Vinckeia and three CSIs each that reliably group P. malariae with members of the subgenus Plasmodium and P. ovale within the subgenus Vinckeia, respectively. These results provide a reliable framework for understanding the evolutionary relationships among the Plasmodium/Piroplasmida species. Further, in view of the exclusivity of the described molecular markers for the indicated groups of hematozoa species, particularly large numbers of unique characteristics that are specific for all Plasmodium species, they provide important molecular tools for biochemical/genetic studies and for developing novel diagnostics and therapeutics for these organisms.

Cladistic analysis of the Early Cambrian olenelloid trilobites

1998 ◽  
Vol 72 (1) ◽  
pp. 59-78 ◽  
Author(s):  
Bruce S. Lieberman
Keyword(s):  
Phylogenetic Analysis ◽  
Cladistic Analysis ◽  
Intraspecific Variability ◽  
Evolutionary Relationships ◽  
Early Cambrian ◽  
New Genera ◽  
Phylogenetic Structure ◽  
Major Clade ◽  
Lateral Margins

A phylogenetic analysis was used to determine evolutionary relationships within the Early Cambrian superfamily Olenelloidea Walcott, 1890. Phylogenetic patterns within the suborder Olenellina Walcott, 1890, which contains the Olenelloidea and the Fallotaspidoidea Hupé, 1953, are also discussed. The Olenelloidea are monophyletic, and synapomorphies uniting them include the condition of the ocular lobes where they intersect the frontal lobe of the glabella, and the condition of the lateral margins of the glabellar lobes. In contrast, taxa formerly assigned to the Fallotaspidoidea are shown to represent a paraphyletic grade of several genera, some more closely related to the Olenelloidea, and some more closely related to the Redlichiina Richter, 1933. Seventy-nine exoskeletal characters were coded for 26 taxa within the Olenellina. These included 22 ingroup Olenelloidea and four outgroup taxa that have traditionally been assigned to the Fallotaspidoidea. When subjected to parsimony analysis these character data yielded a single most parsimonious cladogram that provides an hypothesis of relationship for the generic clades within the superfamily. Two new genera are recognized herein, Fritzolenellus and Lochmanolenellus. It has been argued that genetic flexibility was so great and trilobite morphology was so plastic in the Early Cambrian that suprageneric classification of Early Cambrian trilobites is precluded. Although levels of intraspecific variability may have been slightly higher in the Early Cambrian relative to the mid Paleozoic, based on the extent of polymorphic character codings, it was not so high as to obviate attempts at recovering phylogenetic structure in a major clade of Early Cambrian taxa. In addition, the consistency index recovered by this analysis is not unduly low for a phylogenetic database of this size. The phylogenetic analysis also has bearing on patterns of allometric heterochrony, which have often been held to be significant in Early Cambrian trilobites. The paedomorphic retention of advanced genal spines into the adult probably evolved at least four times. Three of the episodes can be best described as neoteny, the fourth, as progenesis. Finally, based on the phylogeny, it is likely that rates of speciation in trilobites may have been two to three times higher in the Early Cambrian than in the mid Paleozoic.

Morphological and molecular characterisation of two species of Aporcella Andrássy, 2002 (Nematoda: Dorylaimida: Aporcelaimidae) from Iran, with new insights into the phylogeny of the genus

Nematology ◽  
2019 ◽  
Vol 21 (6) ◽  
pp. 655-665 ◽  
Author(s):  
Arezoo Naghavi ◽  
Gholamreza Niknam ◽  
Nasir Vazifeh ◽  
Reyes Peña-Santiago
Keyword(s):  
Fruit Trees ◽  
Morphological Data ◽  
Evolutionary Relationships ◽  
Molecular Characterisation ◽  
Neck Length ◽  
Molecular Analyses ◽  
Major Clade ◽  
The Future ◽  
The Relationship

Summary Two species, one new and another known, of Aporcella, isolated from the rhizosphere of fruit trees in East Azarbaijan, Iran, are described, including morphological data and D2-D3 rDNA LSU sequences. Aporcella malekimilanii sp. n. is characterised by its 1.9-2.7 mm long body, lateral chord bearing glandular bodies, lip region offset by weak constriction and 14-17 μm broad, odontostyle 13-15 μm long with aperture occupying 60% of its length, neck 476-619 μm long, pharyngeal expansion occupying 58-63% of total neck length, uterus simple and 91-100 μm long, V = 55-61, tail conical (44-56 μm, c = 41-58, c′ = 1.2-1.7) with finely rounded tip and a short terminal hyaline portion, and male unknown. New data are provided for A. vitrinus, whose Iranian material fits very well the known populations of the species. Molecular analyses reveal close evolutionary relationships of the two species with other representatives of the genus, supporting its monophyly, and confirm that they belong to a major clade with non-aporcelaimid taxa, the relationship with discolaims deserving further attention in the future.

Characterisation of the dimorphic Deladenus beddingi n. sp. and its associated woodwasp and fungus

Nematology ◽  
2018 ◽  
Vol 20 (10) ◽  
pp. 939-955 ◽  
Author(s):  
E. Erin Morris ◽  
S. Patricia Stock ◽  
Louela A. Castrillo ◽  
David W. Williams ◽  
Ann E. Hajek
Keyword(s):  
New Species ◽  
Excretory Pore ◽  
Phylogenetic Relationships ◽  
Species Complex ◽  
Nematode Species ◽  
Evolutionary Relationships ◽  
Morphometric Traits ◽  
Molecular Analyses ◽  
Dimorphic Species ◽  
Multilocus Sequencing

Summary A new dimorphic species of Deladenus isolated from Sirex californicus from Washington, USA, is described as D. beddingi n. sp. Evolutionary relationships of the new species with other Deladenus species were assessed using multilocus sequencing. Phylogenetic relationships derived from analyses of mtCO1 and ITS showed D. beddingi n. sp. to be genetically distinct from other North American Deladenus parasitising Sirex. Molecular analyses indicated that D. beddingi n. sp. is a member of the D. siricidicola species complex, which also includes undescribed native Deladenus from Sirex cyaneus and S. nitidus, and D. siricidicola from S. noctilio. Mycophagous adults were characterised by the position of the excretory pore, which was located 32 (22-52) and 48 (38-69) μm anterior to the hemizonid in mycophagous females and males, respectively. Typologically, the new species is most similar to D. siricidicola, D. proximus and D. nitobei, but can be distinguished from these species by several morphometric traits, including the value of ratios a, b, c of the mycophagous females and males, ratio b of the infective females, and the morphology of the tail of the mycophagous females, which is narrow and gradually tapering. This novel nematode species feeds on the fungus Amylostereum chailletii during its mycophagous phase. Experimental results showed very little reproduction by D. beddingi n. sp. when feeding on A. areolatum compared to robust reproduction when feeding on A. chailletii.

scholarly journals Diversity Surveys and Evolutionary Relationships of aoxB Genes in Aerobic Arsenite-Oxidizing Bacteria

2008 ◽  
Vol 74 (14) ◽  
pp. 4567-4573 ◽  
Author(s):  
Marianne Quéméneur ◽  
Audrey Heinrich-Salmeron ◽  
Daniel Muller ◽  
Didier Lièvremont ◽  
Michel Jauzein ◽  
...  
Keyword(s):  
Contaminated Soils ◽  
Protein Sequences ◽  
Essential Amino Acids ◽  
Evolutionary Relationships ◽  
16S Rrna Phylogeny ◽  
Genes Encoding ◽  
Rrna Phylogeny ◽  
Environmental Surveys ◽  
Taxonomic Groups ◽  
Arsenite Oxidizing Bacteria

ABSTRACT A new primer set was designed to specifically amplify ca. 1,100 bp of aoxB genes encoding the As(III) oxidase catalytic subunit from taxonomically diverse aerobic As(III)-oxidizing bacteria. Comparative analysis of AoxB protein sequences showed variable conservation levels and highlighted the conservation of essential amino acids and structural motifs. AoxB phylogeny of pure strains showed well-discriminated taxonomic groups and was similar to 16S rRNA phylogeny. Alphaproteobacteria-, Betaproteobacteria-, and Gammaproteobacteria-related sequences were retrieved from environmental surveys, demonstrating their prevalence in mesophilic As-contaminated soils. Our study underlines the usefulness of the aoxB gene as a functional marker of aerobic As(III) oxidizers.

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