Molecular characterisation and phylogenetic relationships of sedentary nematodes of the genus Meloinema Choi & Geraert, 1974 (Nematoda: Tylenchida)

Nematology ◽  
2020 ◽  
pp. 1-9
Author(s):  
Sergei A. Subbotin ◽  
Donggeun Kim
Keyword(s):  
Phylogenetic Trees ◽  
18S Rrna ◽  
Rrna Genes ◽  
Rrna Gene ◽  
28S Rrna ◽  
Molecular Characterisation ◽  
Sister Relationship ◽  
The Family ◽  
18S Rrna Genes ◽  
Relationship Of

Summary Molecular characterisation of two species of Meloinema: M. chitwoodi from Oregon, USA, and M. odesanens from South Korea, is given based on the partial 18S rRNA, the D2-D3 of 28S rRNA, ITS rRNA, and COI gene sequences. In the phylogenetic trees, Meloinema clustered with Meloidogyne, in a basal position and more closely with Meloidogyne indica and M. nataliei. The Shimodaira-Hasegawa (SH) maximum likelihood testing of an alternative topology with two gene fragments (D2-D3 of 28S rRNA and 18S rRNA genes) did not reject a sister relationship of Meloidogyne and Meloinema. Molecular results confirmed the view of Siddiqi (2000) that Meloidogyne and Meloinema evolved from a Pratylenchidae-type ancestor. The clade Meloinema + Meloidogyne + Nacobbus was rejected by the SH test of the D2-D3 of 28S rRNA gene sequence dataset. The molecular results suggested that the genus Nacobbus should be placed not in the Meloidogynidae, but in a separate subfamily, the Nacobbinae, under the family Pratylenchidae.

Systematic status of the caridean families Gnathophyllidae Dana and Hymenoceridae Ortmann (Crustacea : Decapoda): a preliminary examination based on nuclear rDNA sequences

2007 ◽  
Vol 21 (6) ◽  
pp. 613 ◽  
Author(s):  
M. Mitsuhashi ◽  
Y. W. Sin ◽  
H. C. Lei ◽  
T.-Y. Chan ◽  
K. H. Chu
Keyword(s):  
Phylogenetic Trees ◽  
18S Rrna ◽  
Rrna Genes ◽  
28S Rrna ◽  
Nuclear Rdna ◽  
Rdna Sequences ◽  
Preliminary Examination ◽  
The Family ◽  
Close Relationship ◽  
Paraphyletic Assemblage

The systematic positions of the caridean families Gnathophyllidae and Hymenoceridae are inferred based on analyses of nuclear 18S rRNA and 28S rRNA genes. The phylogenetic trees based on 18S rRNA and 28S rRNA from selected species of one genus of the family Gnathophyllidae, two genera of the family Hymenoceridae, one genus of the family Anchistioididae, eight genera of the subfamily Pontoniinae and five genera of the subfamily Palaemoninae show a close relationship between Hymenoceridae, Gnathophyllidae and Pontoniinae, with the last group constituting a paraphyletic assemblage. This result concurs with the morphology of maxilla in the first zoea, but not the shape of the third maxilliped in adults, based on which Gnathophyllidae and Hymenoceridae are treated as families. Molecular analysis supports the similarities in larval morphology between Hymenoceridae, Gnathophyllidae and Pontoniinae and therefore draws into question the familial status of the former two groups.

Phylogeny of hymenolepidids (Cestoda: Cyclophyllidea) from mammals: sequences of 18S rRNA and COI genes confirm major clades revealed by the 28S rRNA analyses

2021 ◽  
Vol 95 ◽  
Author(s):  
B. Neov ◽  
G.P. Vasileva ◽  
G. Radoslavov ◽  
P. Hristov ◽  
D.T.J. Littlewood ◽  
...  
Keyword(s):  
Ribosomal Rna ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
The Other ◽  
Rrna Genes ◽  
Host Switching ◽  
28S Rrna ◽  
Mitochondrial Cytochrome ◽  
Rapid Radiation ◽  
18S Rrna Genes

Abstract The aim of the study is to test a hypothesis for the phylogenetic relationships among mammalian hymenolepidid tapeworms, based on partial (D1–D3) nuclear 28S ribosomal RNA (rRNA) genes, by estimating new molecular phylogenies for the group based on partial mitochondrial cytochrome c oxidase I (COI) and nuclear 18S rRNA genes, as well as a combined analysis using all three genes. New sequences of COI and 18S rRNA genes were obtained for Coronacanthus integrus, C. magnihamatus, C. omissus, C. vassilevi, Ditestolepis diaphana, Lineolepis scutigera, Spasskylepis ovaluteri, Staphylocystis tiara, S. furcata, S. uncinata, Vaucherilepis trichophorus and Neoskrjabinolepis sp. The phylogenetic analyses confirmed the major clades identified by Haukisalmi et al. (Zoologica Scripta 39: 631–641, 2010): Ditestolepis clade, Hymenolepis clade, Rodentolepis clade and Arostrilepis clade. While the Ditestolepis clade is associated with soricids, the structure of the other three clades suggests multiple evolutionary events of host switching between shrews and rodents. Two of the present analyses (18S rRNA and COI genes) show that the basal relationships of the four mammalian clades are branching at the same polytomy with several hymenolepidids from birds (both terrestrial and aquatic). This may indicate a rapid radiation of the group, with multiple events of colonizations of mammalian hosts by avian parasites.

scholarly journals Crenosoma striatum in lungs of European hedgehogs (Erinaceus europeus) from Portugal

2020 ◽  
Vol 57 (2) ◽  
pp. 179-184
Author(s):  
P. F. Barradas ◽  
A. R. Flores ◽  
T. L. Mateus ◽  
F. Carvalho ◽  
F. Gärtner ◽  
...  
Keyword(s):  
Molecular Characterization ◽  
18S Rrna ◽  
Population Sample ◽  
Genetic Data ◽  
Rrna Genes ◽  
12S Rrna ◽  
Rrna Gene ◽  
Mitochondrial 12S Rrna ◽  
18S Rrna Genes

SummaryCrenosoma striatum is a host-specifi c metastrongiloid nematode causing respiratory tract disease in hedgehogs (Erinaceus europaeus). Since few studies have reported C. striatum in hedgehogs and little genetic data is available concerning this lungworm, this study aimed to determine the occurrence of C. striatum in a population sample of hedgehogs from Portugal, additionally providing morphological, histological and molecular data. From 2017 to 2018 a survey of infection was carried out in 11 necropsied hedgehogs. Worms were extracted from fresh lung tissues and microscopically evaluated. Molecular characterization of partial mitochondrial (12S rRNA) and nuclear (18S rRNA) genes was performed. The presence of lungworms in pulmonary tissues of five hedgehogs (45.5%) was detected. Morphological and histopathological analyses evidenced adult forms of nematodes consistent with C. striatum. Molecular characterization of 18S rRNA genes confirmed the classifi cation as C. striatum. Also, novel genetic data characterizing the mitochondrial (12S rRNA) gene of C. striatum is presented.This is the first report of C. striatum infection in hedgehogs of Portugal. The findings here reported provide new insights regarding the geographic distribution and the molecular identification of this lungworm species.

Molecular and morphometric characterisation of Xiphinema globosum Sturhan, 1978 (Nematoda: Longidoridae) from Spain

Nematology ◽  
2011 ◽  
Vol 13 (1) ◽  
pp. 17-28 ◽  
Author(s):  
Blanca Landa ◽  
Carolina Cantalapiedra-Navarrete ◽  
Juan Palomares-Rius ◽  
Pablo Castillo ◽  
Carlos Gutiérrez-Gutiérrez
Keyword(s):  
Phylogenetic Trees ◽  
18S Rrna ◽  
Matrix Representation ◽  
Natural Environments ◽  
28S Rrna ◽  
Parsimony Method ◽  
Rdna Genes ◽  
Supertree Method ◽  
The Matrix ◽  
Relationship Of

AbstractDuring a recent nematode survey in natural environments of the Los Alcornocales Regional Park narrow valleys, viz., the renowned 'canutos' excavated in the mountains that maintain a humid microclimate, in southern Spain, an amphimictic population of Xiphinema globosum was identified. Morphological and morphometric studies on this population fit the original and previous descriptions and represent the first report from Spain and southern Europe. Molecular characterisation of X. globosum from Spain using D2-D3 expansion regions of 28S rRNA, 18S rRNA and ITS1-rRNA is provided and maximum likelihood and Bayesian inference analysis were used to reconstruct phylogenetic relationships within X. globosum and other Xiphinema species. A supertree solution of the different phylogenetic trees obtained in this study and in other published studies using rDNA genes are presented using the matrix representation parsimony method (MRP) and the most similar supertree method (MSSA). The results revealed a closer phylogenetic relationship of X. globosum with X. diversicaudatum, X. bakeri and with some sequences of unidentified Xiphinema spp. deposited in GenBank.

Morphological and molecular characterisation of Helicotylenchus ciceri n. sp. and H. scoticus Boag & Jairajpuri, 1985 (Nematoda: Hoplolaimidae) from Iran

Nematology ◽  
2020 ◽  
Vol 22 (6) ◽  
pp. 611-626
Author(s):  
Fariba Mohammadi Zameleh ◽  
Akbar Karegar ◽  
Reza Ghaderi ◽  
Abbas Mokaram Hesar
Keyword(s):  
New Species ◽  
Excretory Pore ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Rrna Genes ◽  
28S Rrna ◽  
Molecular Characterisation ◽  
Closely Related Species ◽  
Partial 18S ◽  
Molecular Characters

Summary Helicotylenchus ciceri n. sp. and H. scoticus are described and illustrated based on morphological, morphometric and molecular characters. The new species is characterised by a conical and truncated lip region with five or six distinct annuli, stylet 32-37 μm long with anteriorly concave knobs, secretory-excretory pore posterior to the pharyngo-intestinal valve, dorsally convex-conoid tail with a terminal projection, phasmids 14 (7-20) annuli anterior to the level of anus, empty spermatheca and absence of males. Intraspecific variation of 16 populations of H. scoticus, collected from chickpea and lentil fields in Kermanshah province, western Iran, is discussed. The results of the phylogenetic analyses based on the sequences of the partial 18S rRNA, D2-D3 expansion segments of 28S rRNA and ITS rRNA genes are provided for the studied species, confirming their differences from each other and determining the position of them and their relationships with closely related species.

scholarly journals Design and Validation of Four New Primers for Next-Generation Sequencing To Target the 18S rRNA Genes of Gastrointestinal Ciliate Protozoa

2014 ◽  
Vol 80 (17) ◽  
pp. 5515-5521 ◽  
Author(s):  
Suzanne L. Ishaq ◽  
André-Denis G. Wright
Keyword(s):  
18S Rrna ◽  
18S Rrna Gene ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Content Type ◽  
Hypervariable Regions ◽  
Blast Database ◽  
Primer Sets ◽  
18S Rrna Genes ◽  
Ciliate Protozoa

ABSTRACTFour new primers and one published primer were used to PCR amplify hypervariable regions within the protozoal 18S rRNA gene to determine which primer pair provided the best identification and statistical analysis. PCR amplicons of 394 to 498 bases were generated from three primer sets, sequenced using Roche 454 pyrosequencing with Titanium, and analyzed using the BLAST database (NCBI) and MOTHUR version 1.29. The protozoal diversity of rumen contents from moose in Alaska was assessed. In the present study, primer set 1, P-SSU-316F and GIC758R (amplicon of 482 bases), gave the best representation of diversity using BLAST classification, and the set amplifiedEntodinium simplexandOstracodiniumspp., which were not amplified by the other two primer sets. Primer set 2, GIC1080F and GIC1578R (amplicon of 498 bases), had similar BLAST results and a slightly higher percentage of sequences that were identified with a higher sequence identity. Primer sets 1 and 2 are recommended for use in ruminants. However, primer set 1 may be inadequate to determine protozoal diversity in nonruminants. The amplicons created by primer set 1 were indistinguishable for certain species within the generaBandia,Blepharocorys,Polycosta, andTetratoxumand betweenHemiprorodon gymnoprosthiumandProrodonopsiscoli, none of which are normally found in the rumen.

Molecular identification ofSarcocystisspp. helped to define the origin of green pythons (Morelia viridis) confiscated in Germany

Parasitology ◽  
2013 ◽  
Vol 141 (5) ◽  
pp. 646-651 ◽  
Author(s):  
GASTÓN MORÉ ◽  
NIKOLA PANTCHEV ◽  
DALAND C. HERRMANN ◽  
MAJDA GLOBOKAR VRHOVEC ◽  
SABINE ÖFNER ◽  
...  
Keyword(s):  
18S Rrna ◽  
Sequence Data ◽  
18S Rrna Gene ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Intermediate Hosts ◽  
Apicomplexan Parasites ◽  
Large Numbers ◽  
Wide Range ◽  
18S Rrna Genes

SUMMARYSarcocystisspp. represent apicomplexan parasites. They usually have a heteroxenous life cycle. Around 200 species have been described, affecting a wide range of animals worldwide, including reptiles. In recent years, large numbers of reptiles have been imported into Europe as pets and, as a consequence, animal welfare and species protection issues emerged. A sample of pooled feces from four confiscated green pythons (Morelia viridis) containingSarcocystisspp. sporocysts was investigated. These snakes were imported for the pet trade and declared as being captive-bred. Full length 18S rRNA genes were amplified, cloned into plasmids and sequenced. Two differentSarcocystisspp. sequences were identified and registered asSarcocystissp. fromM. viridisin GenBank. Both showed a 95–97% sequence identity with the 18S rRNA gene ofSarcocystis singaporensis.Phylogenetic analysis positioned these sequences together with otherSarcocystisspp. from snakes and rodents as definitive and intermediate hosts (IH), respectively. Sequence data and also the results of clinical and parasitological examinations suggest that the snakes were definitive hosts forSarcocystisspp. that circulate in wild IH. Thus, it seems unlikely that the infected snakes had been legally bred. Our research shows that information on the infection of snakes withSarcocystisspp. may be used to assess compliance with regulations on the trade with wildlife species.

scholarly journals Real-time PCRs for detection of Trichomonas vaginalis β-tubulin and 18S rRNA genes in female genital specimens

2007 ◽  
Vol 56 (6) ◽  
pp. 772-777 ◽  
Author(s):  
Paul Simpson ◽  
Geoff Higgins ◽  
Ming Qiao ◽  
Russell Waddell ◽  
Tuckweng Kok
Keyword(s):  
Real Time ◽  
Trichomonas Vaginalis ◽  
18S Rrna ◽  
Clinical Manifestations ◽  
Developed Countries ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Wet Mount ◽  
Increased Risk ◽  
18S Rrna Genes

Trichomonas vaginalis is the cause of one of the most common types of vaginitis, trichomoniasis. The incidence of trichomoniasis in developed countries has decreased substantially during the past decade, but high prevalence of this disease can still be found in rural and remote areas of Australia. Clinical manifestations of symptomatic women are generally non-specific, but include vaginal discharge, vaginitis and irritation. T. vaginalis infection has also been linked to the increased risk of human immunodeficiency virus transmission. Current diagnosis of T. vaginalis relies on the visualization of motile organisms in a wet-mount preparation. Culture is used mainly in reference laboratories. The latter two methods require viable organisms and would not be suitable for use where transportation of specimens can be delayed. Two real-time fluorescence resonance energy transfer (FRET) hybridization probe PCR assays were used in this study to test for T. vaginalis DNA, targeting the β-tubulin and 18S rRNA genes. We tested 500 randomly selected female patients, in an STD setting, for T. vaginalis DNA. The FRET PCRs targeting the β-tubulin gene and the 18S rRNA gene detected 96 % (85/89) and 100 % (89/89) , respectively, of the positive specimens (first-void urine sample or genital swabs). Wet-mount microscopy was performed on 76 of these PCR-positive specimens and showed a sensitivity of 38 % (29/76). The prevalence, by PCR, of trichomoniasis was 18 % in this study. The two real-time PCRs developed in this study, targeting different genetic regions of the organism, provide a rapid, sensitive and specific diagnosis of T. vaginalis infection.

Processing of truncated mouse or human rRNA transcribed from ribosomal minigenes transfected into mouse cells

1994 ◽  
Vol 14 (6) ◽  
pp. 4044-4056
Author(s):  
K V Hadjiolova ◽  
A Normann ◽  
J Cavaillé ◽  
E Soupène ◽  
S Mazan ◽  
...  
Keyword(s):  
18S Rrna ◽  
Processing System ◽  
Rrna Genes ◽  
In Vitro Assays ◽  
Rrna Gene ◽  
28S Rrna ◽  
Rrna Processing ◽  
Mouse Cells

The processing of pre-rRNA in eukaryotic cells involves a complex pattern of nucleolytic reactions taking place in preribosomes with the participation of several nonribosomal proteins and small nuclear RNAs. The mechanism of these reactions remains largely unknown, mainly because of the absence of faithful in vitro assays for most processing steps. We have developed a pre-rRNA processing system using the transient expression of ribosomal minigenes transfected into cultured mouse cells. Truncated mouse or human rRNA genes are faithfully transcribed under the control of mouse promoter and terminator signals. The fate of these transcripts is analyzed by the use of reporter sequences flanking the rRNA gene inserts. Both mouse and human transcripts, containing the 3' end of 18S rRNA-encoding DNA (rDNA), internal transcribed spacer (ITS) 1, 5.8S rDNA, ITS 2, and the 5' end of 28S rDNA, are processed predominantly to molecules coterminal with the natural mature rRNAs plus minor products corresponding to cleavages within ITS 1 and ITS 2. To delineate cis-acting signals in pre-rRNA processing, we studied series of more truncated human-mouse minigenes. A faithful processing at the 18S rRNA/ITS 1 junction can be observed with transcripts containing only the 60 3'-terminal nucleotides of 18S rRNA and the 533 proximal nucleotides of ITS 1. However, further truncation of 18S rRNA (to 8 nucleotides) or of ITS 1 (to 48 nucleotides) abolishes the cleavage of the transcript. Processing at the ITS 2/28S rRNA junction is observed with truncated transcripts lacking the 5.8S rRNA plus a major part of ITS 2 and containing only 502 nucleotides of 28S rRNA. However, further truncation of the 28S rRNA segment to 217 nucleotides abolishes processing. Minigene transcripts containing most internal sequences of either ITS 1 or ITS 2, but devoid of ITS/mature rRNA junctions, are not processed, suggesting that the cleavages in vivo within either ITS segment are dependent on the presence in cis of mature rRNA sequences. These results show that the major cis signals for pre-rRNA processing at the 18S rRNA/ITS 1 or the ITS2/28S rRNA junction involve solely a limited critical length of the respective mature rRNA and adjacent spacer sequences.

Molecular characterisation of two known species of Paratylenchus Micoletzky, 1922 from Iran with notes on the validity of Paratylenchus audriellus Brown, 1959

Nematology ◽  
2016 ◽  
Vol 18 (5) ◽  
pp. 591-604 ◽  
Author(s):  
Mehrab Esmaeili ◽  
Ramin Heydari ◽  
Pablo Castillo ◽  
Mozhgan Ziaie Bidhendi ◽  
Juan E. Palomares-Rius
Keyword(s):  
18S Rrna ◽  
First Record ◽  
18S Rrna Gene ◽  
Rrna Gene ◽  
28S Rrna ◽  
Molecular Characterisation ◽  
Female Tail ◽  
Valid Taxon ◽  
Two Populations ◽  
Partial 18S

During a survey on pin nematodes in western Iran, two populations of Paratylenchus audriellus and Paratylenchus tenuicaudatus were collected and subsequently analysed morphologically and molecularly. Paratylenchus audriellus is characterised by the long stylet (48-61 μm) and the typical female tail with a characteristic claw-like process with sharply pointed terminus. To our knowledge, the Iranian population of P. tenuicaudatus is the first record from Iran. The molecular characterisation of P. audriellus nematodes using the D2-D3 of 28S rRNA and the partial 18S rRNA gene sequences revealed that this species is clearly separated from P. straeleni and should be considered as a valid taxon.

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