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Seminars in Cell & Developmental Biology Mar 2019Pigment cells serve a variety of important uses across the animal kingdom, and in many species can change and regenerate throughout the lifetime of the organism. The... (Review)
Review
Pigment cells serve a variety of important uses across the animal kingdom, and in many species can change and regenerate throughout the lifetime of the organism. The functions of these cells, as well as their origins in both embryonic development and adult regeneration, are not fully understood. Here, we review advances in the study of pigment cells in the freshwater planarian, a model system for stem cell biology and regeneration. Freshwater planarians produce at least three pigment types to generate brown eye and body colouration: melanin, porphyrin, and ommochrome. The body pigments of planarians are produced and contained by a specialized, highly dendritic cell type located in the subepidermal parenchymal space. This cell type is specifically ablated following intense light exposure, a characteristic which has been exploited to discover the gene expression and regeneration of planarian pigment cells. Regenerating pigment cells progress through an immature state marked by upregulation of pigment synthesis genes before differentiating into mature pigment cells; these two states are dynamically regulated in homeostasis to maintain constant body pigmentation. The transcription factors Albino, FoxF-1, and Ets-1, as well as an FGFR-like molecule, are required for proper maintenance of the pigment lineage in both regeneration and homeostasis. These discoveries set the stage for research into external signals that regulate the pigment lineage, as well as possible functions for pigment cells in planarians, including the extra-ocular light response. These insights will address outstanding questions about the evolutionarily-conserved biology of pigment cells.
Topics: Animals; Cell Lineage; Pigmentation; Planarians; Platyhelminths
PubMed: 29758350
DOI: 10.1016/j.semcdb.2018.05.010 -
The Journal of Parasitology May 2023The parasites infecting invasive carps in North America (all Cypriniformes: Xenocyprididae: grass carp, Ctenopharyngodon idella [Valenciennes, 1844]; silver carp,...
FIRST RECORD OF A PARASITE, DACTYLOGYRUS CF. SKRJABINI (MONOGENOIDEA: DACTYLOGYRIDAE), INFECTING INVASIVE SILVER CARP, HYPOPHTHALMICHTHYS MOLITRIX (VALENCIENNES, 1844) (CYPRINIFORMES: XENOCYPRIDIDAE) IN NORTH AMERICA.
The parasites infecting invasive carps in North America (all Cypriniformes: Xenocyprididae: grass carp, Ctenopharyngodon idella [Valenciennes, 1844]; silver carp, Hypophthalmichthys molitrix [Valenciennes, 1844]; bighead carp, Hypophthalmichthys nobilis [Richardson, 1845]; and black carp, Mylopharyngodon piceus [Richardson, 1846]) are little studied, and no parasite has been reported from silver carp there. We herein surveyed silver carp from Barkley Reservoir and Cheatham Reservoir (Cumberland River, Tennessee; June and December 2021) and the White River (Arkansas; May 2022) and collected numerous monogenoid specimens infecting the pores on the outer face of the gill raker plate. We heat-killed, formalin-fixed, and routinely stained some specimens for morphology and preserved others in 95% ethanol for DNA extraction and sequencing of the large subunit ribosomal DNA (28S). We identified our specimens as Dactylogyrus cf. skrjabini because they had a dorsal anchor deep root that is much longer than the superficial root, an approximately parallel penis and accessory piece, and a relatively large marginal hook pair V. No type specimen of Dactylogyrus skrjabiniAkhmerov, 1954 (type host and locality is silver carp, Amur River, Russia) is publicly available, but we borrowed several vouchers (NSMT-Pl 6393) that infected the gill rakers of silver carp captured in the Watarase River, Japan. The original description of D. skrjabini was highly stylized and diagrammatical, differing from the specimens we studied from North America and Japan by the dorsal anchor having a superficial root and shaft that comprise a strongly C-shaped hook (the superficial root curves toward the dorsal anchor point) (vs. superficial root straight, at ∼45° angle to deep root and directed away from the dorsal anchor point), a single, much reduced transverse bar that is narrow for its entire breadth (vs. dorsal and ventral transverse bars robust and broad, having an irregular outline), an accessory piece that lacks digitiform projections (vs. accessory piece with 4 digitiform projections), and an accessory piece that lacks a half cardioid-shaped process (vs. accessory piece having a half cardioid-shaped process). Our 28S sequences (generated from 4 specimens of D. cf. skrjabini: 2 from Tennessee [763 base pairs (bp)] and 2 from Arkansas [776 bp]) were identical to 1 ascribed to D. skrjabini from Japan. The present study is the first verifiable and credible report of a parasite from silver carp in North America and the first nucleotide information for a parasite from silver carp in North America.
Topics: Animals; Carps; Helminthiasis, Animal; Platyhelminths; Species Specificity; Tennessee; RNA, Ribosomal, 28S; Phylogeny
PubMed: 37339076
DOI: 10.1645/23-11 -
BMC Veterinary Research May 2021Platyhelminth infections of livestock can result in considerable economic losses. This study aims to evaluate the spatial frequency of cystic echinococcosis (CE),...
BACKGROUND
Platyhelminth infections of livestock can result in considerable economic losses. This study aims to evaluate the spatial frequency of cystic echinococcosis (CE), dicrocoeliasis, and fascioliasis in livestock slaughtered in Iran during the years 2015-2019 and estimate direct costs associated with organ condemnation due to these parasites.
METHODS
Abattoir data from 413 abattoirs representing all 31 Iranian provinces were collected from the Iran Veterinary Organization. Infection prevalence was calculated per year at the province level. The Local Moran's I statistic was performed to evaluate spatial autocorrelation of animals positive at slaughter for the years 2015-2019. Direct costs associated with condemned livers were calculated for each parasitic condition, with costs associated with condemned lungs also included for CE.
RESULTS
Overall prevalence values for the study timeframe were as follows: sheep and goat fascioliasis 1.56% (95% CI: 1.56-1.56%), cattle fascioliasis 3.86% (95% CI: 3.85-3.88%), sheep and goat dicrocoeliasis 4.63% (95% CI: 4.62-4.63%), cattle dicrocoeliasis 3.08% (95% CI: 3.07-3.09%), sheep and goat CE 5.32% (95% CI: 5.32-5.33%), and cattle CE 7.26% (95% CI: 7.24-7.28%). Northwest Iran had the highest prevalence of CE and fascioliasis. High infection areas for Dicrocoelium spp. included the provinces of Zanjan, Gilan, Qazvin, and Tehran, which are located in northern Iran. Direct economic losses for sheep and goat fascioliasis, dicrocoeliasis, and CE for the study period were US$13,842,759, US$41,771,377, and US$22,801,054, respectively. Direct economic losses for cattle fascioliasis, dicrocoeliasis, and CE for the study period were US$1,989,200, US$1,668,986, and US$2,656,568, respectively.
CONCLUSION
Our findings provide valuable data for future monitoring of these important parasitic diseases in Iranian livestock. Disease control strategies are required to reduce the economic and public health impact of these platyhelminths.
Topics: Abattoirs; Animals; Cattle; Cattle Diseases; Dicrocoeliasis; Dicrocoelium; Echinococcosis; Echinococcus; Fasciola; Fascioliasis; Goat Diseases; Goats; Iran; Livestock; Sheep; Sheep Diseases; Zoonoses
PubMed: 33952280
DOI: 10.1186/s12917-021-02888-9 -
PloS One 2021Since the first complete set of Platyhelminth nuclear receptors (NRs) from Schistosoma mansoni were identified a decade ago, more flatworm genome data is available to...
Since the first complete set of Platyhelminth nuclear receptors (NRs) from Schistosoma mansoni were identified a decade ago, more flatworm genome data is available to identify their NR complement and to analyze the evolutionary relationship of Platyhelminth NRs. NRs are important transcriptional modulators that regulate development, differentiation and reproduction of animals. In this study, NRs are identified in genome databases of thirty-three species including in all Platyhelminth classes (Rhabditophora, Monogenea, Cestoda and Trematoda). Phylogenetic analysis shows that NRs in Platyhelminths follow two different evolutionary lineages: 1) NRs in a free-living freshwater flatworm (Schmidtea mediterranea) and all parasitic flatworms share the same evolutionary lineage with extensive gene loss. 2) NRs in a free-living intertidal zone flatworm (Macrostomum lignano) follow a different evolutionary lineage with a feature of multiple gene duplication and gene divergence. The DNA binding domain (DBD) is the most conserved region in NRs which contains two C4-type zinc finger motifs. A novel zinc finger motif is identified in parasitic flatworm NRs: the second zinc finger of parasitic Platyhelminth HR96b possesses a CHC2 motif which is not found in NRs of all other animals studied to date. In this study, novel NRs (members of NR subfamily 3 and 6) are identified in flatworms, this result demonstrates that members of all six classical NR subfamilies are present in the Platyhelminth phylum. NR gene duplication, loss and divergence in Platyhelminths are analyzed along with the evolutionary relationship of Platyhelminth NRs.
Topics: Animals; Evolution, Molecular; Gene Duplication; Phylogeny; Platyhelminths; Receptors, Cytoplasmic and Nuclear; Zinc Fingers
PubMed: 34388160
DOI: 10.1371/journal.pone.0250750 -
Parasitology Nov 2022The complete circular mitogenome of (Platyhelminthes: Paragonimidae) from Japan, obtained by PacBio long-read sequencing, was 17 591 bp and contained 12 protein-coding...
The complete circular mitogenome of (Platyhelminthes: Paragonimidae) from Japan, obtained by PacBio long-read sequencing, was 17 591 bp and contained 12 protein-coding genes (PCGs), 2 mitoribosomal RNA and 22 transfer RNA genes. The 8 gene was absent, and there was a 40 bp overlap between 4L and 4. The long non-coding region (4.3 kb) included distinct types of long and short repeat units. The pattern of base usage for PCGs and the mtDNA coding region overall in Asian and American species (, , and ) and the Indian form of was > > > . On the other hand, East-Asian used > > > . Five Asian and American species and had TTT/Phe, TTG/Leu and GTT/Val as the most frequently used codons, whereas the least-used codons were different in each species and between regional forms of . The phylogenetic tree reconstructed from a concatenated alignment of amino acids of 12 PCGs from 36 strains/26 species/5 families of trematodes confirmed that the Paragonimidae is monophyletic, with 100% nodal support. was resolved as a sister to The clade was clearly separate from remaining congeners. The latter clade was comprised of 2 subclades, one of the East-Asian and the other of the Indian Type 1 samples. Additional mitogenomes in the Paragonimidae are needed for genomic characterization and are useful for diagnostics, identification and genetic/ phylogenetic/ epidemiological/ evolutionary studies of the Paragonimidae.
Topics: Animals; Paragonimus; Genome, Mitochondrial; Phylogeny; Trematoda; Lung
PubMed: 36101009
DOI: 10.1017/S0031182022001184 -
Microbiology Spectrum Jun 2022Because parasites have an inextricable relationship with their host, they have the potential to serve as viral reservoirs or facilitate virus host shifts. And yet,...
Because parasites have an inextricable relationship with their host, they have the potential to serve as viral reservoirs or facilitate virus host shifts. And yet, little is known about viruses infecting parasitic hosts except for blood-feeding arthropods that are well-known vectors of zoonotic viruses. Herein, we uncovered viruses of flatworms (phylum Platyhelminthes, group Neodermata) that specialize in parasitizing vertebrates and their ancestral free-living relatives. We discovered 115 novel viral sequences, including 1 in Macrostomorpha, 5 in Polycladida, 44 in Tricladida, 1 in Monogenea, 15 in Cestoda, and 49 in Trematoda, through data mining. The majority of newly identified viruses constitute novel families or genera. Phylogenetic analyses show that the virome of flatworms changed dramatically during the transition of neodermatans to a parasitic lifestyle. Most Neodermata viruses seem to codiversify with their host, with the exception of rhabdoviruses, which may switch hosts more often, based on phylogenetic relationships. Neodermata rhabdoviruses also have a position ancestral to vertebrate-associated rhabdo viruses, including lyssaviruses, suggesting that vertebrate-associated rhabdoviruses emerged from a flatworm rhabdovirus in a parasitized host. This study reveals an extensive diversity of viruses in Platyhelminthes and highlights the need to evaluate the role of viral infection in flatworm-associated diseases. Little is known about the diversity of parasite-associated viruses and how these viruses may impact parasite fitness, parasite-host interactions, and virus evolution. The discovery of over a hundred viruses associated with a range of free-living and parasitic flatworms, including parasites of economic and clinical relevance, allowed us to compare the viromes of flatworms with contrasting lifestyles. The results suggest that flatworms acquired novel viruses after their transition to a parasitic lifestyle and highlight the possibility that they acquired viruses from their hosts and vice versa. An interesting example is the discovery of flatworm rhabdoviruses that have a position ancestral to rabies viruses and other vertebrate-associated rhabdoviruses, demonstrating that flatworm-associated viruses have emerged in a vertebrate host at least once in history. Therefore, parasitic flatworms may play a role in virus diversity and emergence. The roles that parasite-infecting viruses play in parasite-associated diseases remain to be investigated.
Topics: Animals; Host-Parasite Interactions; Parasites; Phylogeny; Platyhelminths; Viruses
PubMed: 35536058
DOI: 10.1128/spectrum.00138-22 -
Journal of Helminthology Nov 2022(Gusev, ) Gusev, was collected from the so-iuy mullet (Temminck & Schlegel, 1845) from the Black Sea and the Sea of Japan. DNA sequences data for , as well as its...
First morphological and phylogenetic data on (Platyhelminthes: Monogenea) from the Black Sea and the Sea of Japan and molecular evidence of deep divergence of sympatric species parasitizing .
(Gusev, ) Gusev, was collected from the so-iuy mullet (Temminck & Schlegel, 1845) from the Black Sea and the Sea of Japan. DNA sequences data for , as well as its morphological characters from the Sea of Japan were obtained for the first time. Significant morphometric and genetic diversity between specimens of from the Black-Azov Sea region and the Sea of Japan were not found. For the first time, the molecular phylogeny of based on three fragments of the nuclear DNA ribosomal cluster (18S, internal transcribed spacer 1 and 28S) was reconstructed. Molecular analysis of species from the Atlantic and Pacific Oceans revealed a significant phylogenetic distance between and two others species ( and ) from the same host () and region. This result indicates the lack of correspondence between the phylogenetic and geographical closeness of the hosts and the relation of their parasites from the genus .
Topics: Animals; Phylogeny; Black Sea; Japan; Platyhelminths; Trematoda; Smegmamorpha
PubMed: 36377340
DOI: 10.1017/S0022149X22000724 -
International Journal For Parasitology Jan 2022Infections by blood flukes (Cardicola spp.) are considered the most significant health issue for ranched bluefin tuna, a major aquaculture industry in Japan and...
Infections by blood flukes (Cardicola spp.) are considered the most significant health issue for ranched bluefin tuna, a major aquaculture industry in Japan and Australia. The host-parasite interfaces of trematodes, namely their teguments, are particularly rich in carbohydrates, which function both in evasion and modulation of the host immune system, while some are primary antigenic targets. In this study, histochemistry and mass spectrometry techniques were used to profile the glycans of Cardicola forsteri. Fluorescent lectin staining of adult flukes indicates the presence of oligomannose (Concanavalin A-reactive) and fucosylated (Pisum sativum agglutinin-reactive) N-glycans. Additionally, reactivity of succinylated wheat germ agglutinin (s-WGA) was localised to several internal organs of the digestive and monoecious reproductive systems. Glycan structures were further investigated with tandem mass spectrometry, which revealed structures indicated by lectin reactivity. While O-glycans from these adult specimens were not detectable by mass spectrometry, several oligomannose, paucimannosidic, and complex-type N-glycans were identified, including some carrying hexuronic acid and many carrying core xylose. This is, to our knowledge, the first glycomic characterisation of a marine platyhelminth, with broader implications for research into other trematodes.
Topics: Animals; Fish Diseases; Lectins; Parasites; Polysaccharides; Schistosoma; Schistosomatidae; Trematode Infections; Tuna
PubMed: 34391752
DOI: 10.1016/j.ijpara.2021.06.004 -
Acta Parasitologica Sep 2023Bluegill sunfish (Lepomis macrochirus) are a North American sport fish that exhibit two different male morphotypes. Alpha-males are large, colorful, territorial, and...
PURPOSE
Bluegill sunfish (Lepomis macrochirus) are a North American sport fish that exhibit two different male morphotypes. Alpha-males are large, colorful, territorial, and have significant parental investment, while β-males are small, drab, and have two reproductive phenotypes, neither of which involves parental investment. Due to the two different reproductive strategies, the level of interaction between congenerics varies, which may impact parasites that are spread via close contact, such as Monogenoidea that infect the gills. Monogeneans are ectoparasites on the gills and skin of fish hosts that may cause significant pathology in high numbers and be an indicator of host behavior and interaction between hosts.
METHODS
In this study, 328 L. macrochirus (106 α-males, 92 β-males, and 130 females) were necropsied from 8 lakes and ponds in northwestern Virginia to identify and enumerate monogenean parasites from the gills.
RESULTS
Alpha-males had a significantly greater parasite abundance and species richness compared to β-males. This may be due to the increased size and surface area of gills in α-males, increased interaction with females during mating, and stationary behavior when guarding nests, which enhanced the chances of α-males contracting the parasites. This also led to significant differences in the monogenean communities infecting the two morphotypes, which were also significantly influenced by the size of the hosts.
CONCLUSIONS
It is important in future studies regarding parasitism that behavioral morphotypes within a sex, such as α-male and β-male L. macrochirus in this study, be treated separately as behavioral and morphometric differences between them can potentially lead to differences in parasitism.
Topics: Male; Animals; Perciformes; Female; Host-Parasite Interactions; Gills; Platyhelminths; Biodiversity; Sexual Behavior, Animal; Reproductive Behavior
PubMed: 37330944
DOI: 10.1007/s11686-023-00682-1 -
Zoological Science Jun 2020Acotylea is a suborder of Polycladida (Rhabditophora, Platyhelminthes) characterized by lack of a cotyl (sucker-like structure) on the ventral surface of the body. We...
Acotylea is a suborder of Polycladida (Rhabditophora, Platyhelminthes) characterized by lack of a cotyl (sucker-like structure) on the ventral surface of the body. We newly determined partial sequences of two mitochondrial (16S ribosomal RNA and cytochrome oxidase subunit I) and two nuclear (18S and 28S ribosomal RNA) genes from 24 acotylean species (12 families and 14 genera). Based on these sequences in addition to those available in public databases, we inferred the phylogeny of 16 families and 27 genera of Acotylea from molecular phylogenetic analyses (maximum likelihood and Bayesian inference) based on concatenated gene sequences. Our analyses supported three clades corresponding to Discoceloidea, Leptoplanoidea, and Stylochoidea. The phylogenetic position of Callioplanidae remains unclear. Among family- or genus-level taxa, Gnesiocerotidae, Stylochoplanidae, and were not monophyletic. We discuss the validities of Notocomplanidae and , and the family-level assignment of .
Topics: Animals; Genes, Helminth; Genes, Mitochondrial; Helminth Proteins; Phylogeny; Platyhelminths; RNA, Helminth
PubMed: 32549541
DOI: 10.2108/zs190136