Morphometric and molecular analyses of two digenean species in mugilid fish: Lecithaster mugilis Yamaguti, 1970 from Vietnam and L. sudzuhensis n. sp. from southern Russian Far East

2016 ◽  
Vol 91 (3) ◽  
pp. 326-331 ◽  
Author(s):  
V.V. Besprozvannykh ◽  
D.M. Atopkin ◽  
H.D. Ngo ◽  
A.V. Ermolenko ◽  
N. Van Ha ◽  
...  
Keyword(s):  
Coastal Waters ◽  
18S Rrna ◽  
Russian Far East ◽  
Far East ◽  
Rrna Genes ◽  
28S Rrna ◽  
Molecular Analyses ◽  
Digenean Species ◽  
Mississippi Sound ◽  
Halong Bay

AbstractAdult Lecithaster mugilis Yamaguti, 1970 were found in Moolgarda seheli, Valamugil engeli and Liza subviridis in the coastal waters of Cat Ba Island (Halong Bay, Vietnam). Specimens of Lecithaster sudzuhensis n. sp. were found in Mugil cephalus located in an estuary of the Kievka River in the Primorsky region of Russia. Studies have demonstrated that these species share significant morphometric similarities with each other and with specimens of L. helodes Overstreet, 1973 isolated from M. cephalus and Mugil curema from the Mississippi Sound and adjacent waters. These three species differ from one another in the size of the pharynx and ventral sucker and in the ratio of suckers, while they differ from other species in the genus by having a relatively elongated oesophagus. Molecular analysis, using the 18S rRNA and 28S rRNA genes, confirmed the validity of L. mugilis and L. sudzuhensis n. sp. and demonstrated that these species form a shared cluster with L. gibbosus (Rud, 1802).

Evolutionary relationships of the bivalve family Thyasiridae (Mollusca: Bivalvia), monophyly and superfamily status

2007 ◽  
Vol 87 (2) ◽  
pp. 565-574 ◽  
Author(s):  
John D. Taylor ◽  
Suzanne T. Williams ◽  
Emily A. Glover
Keyword(s):  
Fossil Record ◽  
18S Rrna ◽  
Rrna Genes ◽  
Symbiotic Bacteria ◽  
Evolutionary Relationships ◽  
Marine Bivalve ◽  
28S Rrna ◽  
Molecular Analyses ◽  
The Family ◽  
Basal Position

Molecular analyses of 13 species of the marine bivalve family Thyasiridae, using sequences from 18S rRNA and 28S rRNA genes, showed that the family is monophyletic despite the anatomical disparity and inclusion of both chemosymbiotic and asymbiotic species. This new analysis also confirmed that the three families (Thyasiridae, Lucinidae and Ungulinidae), previously included in the Lucinoidea, were not closely related. Four species of Ungulinidae grouped within a clade containing Veneridae, Arcticidae and Mactridae. In relation to a range of other heterodont bivalves, Thyasiridae occupied a near basal position, apart from a clade comprising Carditidae/Astartidae/Crassatellidae. The earliest thyasirid recognized in the fossil record is a species from the Lower Cretaceous of England. Within the Thyasiridae, some groups can be identified but relations between these are weakly supported. Amongst the taxa analysed, those with symbiotic bacteria and two ctenidial demibranchs belong to at least three groups, while there is some support for a clade of asymbiotic taxa with single demibranchs. In recognition of the monophyletic status of the Thyasiridae, distinct from all other heterodont bivalves, we elevate the rank to superfamily Thyasiroidea.

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.

Comparative description of brown algae from the coastal zone of Far East

2015 ◽  
Vol 182 (3) ◽  
pp. 258-268
Author(s):  
Natalia M. Aminina
Keyword(s):  
Coastal Waters ◽  
Brown Algae ◽  
Alginic Acid ◽  
Russian Far East ◽  
Far East ◽  
Saccharina Japonica ◽  
Total Biomass ◽  
Aniva Bay ◽  
Far Eastern ◽  
Comparative Description

Data on stock and distribution of commercial and prospective for harvesting brown algae at the coast of Russian Far East are presented and compared. Their total biomass in the traditional harvesting grounds prevails 3.5 million tons. Saccharina japonica, Saccharina gurjanovae, Cystoseira crassipes have the highest biomass. However, taking into account both the stock and chemical composition of the tissues, Saccharina bongardiana, Arthrothamnus bifidus, and Eualaria fistulosa are the most profitable for harvesting and processing. The algae from the coastal waters of south-western Sakhalin have generally higher content of valuable proteins and minerals, but the content of mannitol and alginic acid is higher in the algae from the coastal waters of Kamchatka and Primorye. Contamination of the algae by toxic elements is considered, as well: in general, the safety indicators allow to regard all basic harvesting grounds of brown algae in the Far Eastern waters as suitable for commercial exploitation, though insignificant excess of the permissible level of lead (0.5 mg/kg) is detected for the brown algae from the coastal waters of Primorye and several sites in the Aniva Bay (southern Sakhalin).

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.

Morphometric and molecular analyses of Carassotrema koreanum Park 1938 and Elonginurus mugilus Lu 1995 (Digenea: Haploporidae) Srivastava, 1937 from the Russian Far East and Vietnam

2019 ◽  
Vol 118 (7) ◽  
pp. 2129-2137 ◽  
Author(s):  
Dmitry M. Atopkin ◽  
Vladimir V. Besprozvannykh ◽  
N. D. Ha ◽  
H. V. Nguyen ◽  
Alexandra Yu Khamatova ◽  
...  
Keyword(s):  
Russian Far East ◽  
Far East ◽  
Molecular Analyses ◽  
The Russian Far East

Review of the systematics, morphology and distribution of Asian Clawed Salamanders, genus Onychodactylus (Amphibia, Caudata: Hynobiidae), with the description of four new species

Zootaxa ◽  
2012 ◽  
Vol 3465 (1) ◽  
pp. 1 ◽  
Author(s):  
NIKOLAY A. POYARKOV, JR. ◽  
JING CHE ◽  
MI-SOOK MIN ◽  
MASAKI KURO-O ◽  
FANG YAN ◽  
...  
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Russian Far East ◽  
Far East ◽  
Molecular Data ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Mitochondrial Coi ◽  
Threat Status ◽  
Molecular Phylogenetic

We describe four new species of Asian Clawed salamanders of the genus Onychodactylus (Caudata: Hynobiidae), basedon fresh material collected during fieldwork in Japan, Korea, the Russian Far East and northeastern China between 2003and 2010, as well as older voucher specimens deposited in several museums. Our analyses comprise all species currentlyrecognized within this genus across its entire distribution range. We follow an integrative taxonomic approach bycombining detailed morphological comparative analyses with molecular phylogenetic analyses. We find significantdifferences among species in this genus, based on morphological and molecular data, which resulted in the recognitionand description of four new species within this genus. The new species have uncorrected molecular divergences of over4.5–7.4% and 1.9–4.1% to their closest relatives in the mitochondrial COI and 16S rRNA genes respectively. In themolecular analyses, we found two very divergent lineages in Korea and Japan that need further investigation, as detailedmorphological data are not available for them. We also discuss our approach to delimit species on salamanders. For thenew species described in this group we evaluate their threat status according to IUCN criteria: O. koreanus sp. nov. Min,Poyarkov & Vieites and O. nipponoborealis sp. nov. Kuro-o, Poyarkov & Vieites are classified as Least Concern, whileO. zhaoermii sp. nov. Che, Poyarkov & Yan and O. zhangyapingi sp. nov. Che, Poyarkov, Li & Yan are classified as Vulnerable (Vu2a).

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.

scholarly journals Correction to: Morphometric and molecular analyses of Carassotrema koreanum park 1938 and Elonginurus mugilus Lu 1995 (Digenea: Haploporidae) Srivastava, 1937 from the Russian Far East and Vietnam

2019 ◽  
Vol 118 (7) ◽  
pp. 2327-2327 ◽  
Author(s):  
Dmitry M. Atopkin ◽  
Vladimir V. Besprozvannykh ◽  
N. D. Ha ◽  
H. V. Nguyen ◽  
Alexandra Yu Khamatova ◽  
...  
Keyword(s):  
Russian Far East ◽  
Far East ◽  
Molecular Analyses ◽  
The Russian Far East

scholarly journals 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.

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.

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