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1.
Nat Commun ; 12(1): 1701, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33723261

RESUMEN

Climate change poses a significant threat to global biodiversity, but freshwater fishes have been largely ignored in climate change assessments. Here, we assess threats of future flow and water temperature extremes to ~11,500 riverine fish species. In a 3.2 °C warmer world (no further emission cuts after current governments' pledges for 2030), 36% of the species have over half of their present-day geographic range exposed to climatic extremes beyond current levels. Threats are largest in tropical and sub-arid regions and increases in maximum water temperature are more threatening than changes in flow extremes. In comparison, 9% of the species are projected to have more than half of their present-day geographic range threatened in a 2 °C warmer world, which further reduces to 4% of the species if warming is limited to 1.5 °C. Our results highlight the need to intensify (inter)national commitments to limit global warming if freshwater biodiversity is to be safeguarded.


Asunto(s)
Peces , Agua Dulce , Calentamiento Global , Animales , Biodiversidad , Cambio Climático , Calor , Modelos Biológicos , Filogenia , Especificidad de la Especie , Temperatura
2.
mBio ; 12(2)2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33727347

RESUMEN

An emerging class of cellular inhibitory proteins has been identified that targets viral glycoproteins. These include the membrane-associated RING-CH (MARCH) family of E3 ubiquitin ligases that, among other functions, downregulate cell surface proteins involved in adaptive immunity. The RING-CH domain of MARCH proteins is thought to function by catalyzing the ubiquitination of the cytoplasmic tails (CTs) of target proteins, leading to their degradation. MARCH proteins have recently been reported to target retroviral envelope glycoproteins (Env) and vesicular stomatitis virus G glycoprotein (VSV-G). However, the mechanism of antiviral activity remains poorly defined. Here we show that MARCH8 antagonizes the full-length forms of HIV-1 Env, VSV-G, Ebola virus glycoprotein (EboV-GP), and the spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), thereby impairing the infectivity of virions pseudotyped with these viral glycoproteins. This MARCH8-mediated targeting of viral glycoproteins requires the E3 ubiquitin ligase activity of the RING-CH domain. We observe that MARCH8 protein antagonism of VSV-G is CT dependent. In contrast, MARCH8-mediated targeting of HIV-1 Env, EboV-GP, and SARS-CoV-2 S protein by MARCH8 does not require the CT, suggesting a novel mechanism of MARCH-mediated antagonism of these viral glycoproteins. Confocal microscopy data demonstrate that MARCH8 traps the viral glycoproteins in an intracellular compartment. We observe that the endogenous expression of MARCH8 in several relevant human cell types is rapidly inducible by type I interferon. These results help to inform the mechanism by which MARCH proteins exert their antiviral activity and provide insights into the role of cellular inhibitory factors in antagonizing the biogenesis, trafficking, and virion incorporation of viral glycoproteins.IMPORTANCE Viral envelope glycoproteins are an important structural component on the surfaces of enveloped viruses that direct virus binding and entry and also serve as targets for the host adaptive immune response. In this study, we investigate the mechanism of action of the MARCH family of cellular proteins that disrupt the trafficking and virion incorporation of viral glycoproteins across several virus families. This research provides novel insights into how host cell factors antagonize viral replication, perhaps opening new avenues for therapeutic intervention in the replication of a diverse group of highly pathogenic enveloped viruses.


Asunto(s)
Proteínas de la Membrana/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas del Envoltorio Viral/metabolismo , Secuencia de Aminoácidos , Células Cultivadas , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Interferones/farmacología , Espacio Intracelular/metabolismo , Proteínas de la Membrana/genética , Mutación , Virus ARN/clasificación , Virus ARN/metabolismo , Especificidad de la Especie , Ubiquitina-Proteína Ligasas/genética , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/genética , Virión/metabolismo , Replicación Viral
3.
Zootaxa ; 4943(1): zootaxa.4943.1.1, 2021 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-33757041

RESUMEN

The model organism Pristionchus pacificus and the genus Pristionchus, Kreis, 1932 have been intensively studied in the last decade with contemporary work focusing on the development, evolution, ecology, behavior, neurobiology, and genomics of this group of organisms. In particular, mechanistic studies on the development and evolution of mouth-form plasticity, predation and associated self-recognition processes enabled unique insight into life history strategies and the evolution of novelty. These studies include a comparative research agenda making use of the 39 available species of Pristionchus, all of which can be studied in living cultures. Sampling efforts revealed that Asia represents a biodiversity hotspot for Pristionchus worms. However, previous samplings have a bias towards northern and island areas, largely for logistic reasons. Here, we report on two extensive sampling trips to the Yunnan and Shaanxi provinces in Mainland China. We report the isolation of nine new Pristionchus species by morphology, morphometrics, mating experiments and genome-wide sequence analysis.


Asunto(s)
Nematodos , Rabdítidos , Animales , China , Nematodos/genética , Filogenia , Especificidad de la Especie
4.
Nat Commun ; 12(1): 1753, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741946

RESUMEN

Mammalian life shows huge diversity, but most groups remain nocturnal in their activity pattern. A key unresolved question is whether mammal species that have diversified into different diel niches occupy unique regions of functional trait space. For 5,104 extant mammals we show here that daytime-active species (cathemeral or diurnal) evolved trait combinations along different gradients from those of nocturnal and crepuscular species. Hypervolumes of five major functional traits (body mass, litter size, diet, foraging strata, habitat breadth) reveal that 30% of diurnal trait space is unique, compared to 55% of nocturnal trait space. Almost half of trait space (44%) of species with apparently obligate diel niches is shared with those that can switch, suggesting that more species than currently realised may be somewhat flexible in their activity patterns. Increasingly, conservation measures have focused on protecting functionally unique species; for mammals, protecting functional distinctiveness requires a focus across diel niches.


Asunto(s)
Ritmo Circadiano/fisiología , Ecosistema , Mamíferos/fisiología , Estaciones del Año , Adaptación Fisiológica , Animales , Biodiversidad , Mamíferos/clasificación , Mamíferos/genética , Fenotipo , Filogenia , Dinámica Poblacional , Carácter Cuantitativo Heredable , Especificidad de la Especie
5.
Nat Commun ; 12(1): 1783, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741994

RESUMEN

Resolving the relationships between the major lineages in the animal tree of life is necessary to understand the origin and evolution of key animal traits. Sponges, characterized by their simple body plan, were traditionally considered the sister group of all other animal lineages, implying a gradual increase in animal complexity from unicellularity to complex multicellularity. However, the availability of genomic data has sparked tremendous controversy as some phylogenomic studies support comb jellies taking this position, requiring secondary loss or independent origins of complex traits. Here we show that incorporating site-heterogeneous mixture models and recoding into partitioned phylogenomics alleviates systematic errors that hamper commonly-applied phylogenetic models. Testing on real datasets, we show a great improvement in model-fit that attenuates branching artefacts induced by systematic error. We reanalyse key datasets and show that partitioned phylogenomics does not support comb jellies as sister to other animals at either the supermatrix or partition-specific level.


Asunto(s)
Ctenóforos/genética , Genoma/genética , Genómica/métodos , Filogenia , Poríferos/genética , Animales , Evolución Biológica , Ctenóforos/clasificación , Modelos Genéticos , Poríferos/clasificación , Especificidad de la Especie
6.
Nat Commun ; 12(1): 1525, 2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33750763

RESUMEN

Anolis lizards originated in continental America but have colonized the Greater Antillean islands and recolonized the mainland, resulting in three major groups (Primary and Secondary Mainland and Greater Antillean). The adaptive radiation in the Greater Antilles has famously resulted in the repeated evolution of ecomorphs. Yet, it remains poorly understood to what extent this island radiation differs from diversification on the mainland. Here, we demonstrate that the evolutionary modularity between girdles and limbs is fundamentally different in the Greater Antillean and Primary Mainland Anolis. This is consistent with ecological opportunities on islands driving the adaptive radiation along distinct evolutionary trajectories. However, Greater Antillean Anolis share evolutionary modularity with the group that recolonized the mainland, demonstrating a persistent phylogenetic inertia. A comparison of these two groups support an increased morphological diversity and faster and more variable evolutionary rates on islands. These macroevolutionary trends of the locomotor skeleton in Anolis illustrate that ecological opportunities on islands can have lasting effects on morphological diversification.


Asunto(s)
Evolución Biológica , Lagartos/anatomía & histología , Lagartos/clasificación , Filogenia , Esqueleto/anatomía & histología , Animales , Región del Caribe , Extremidades , Femenino , Islas , Masculino , Sistema Musculoesquelético/anatomía & histología , Filogeografía , Especificidad de la Especie
7.
Sci Adv ; 7(10)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33658206

RESUMEN

Coronaviruses infect many different species including humans. The last two decades have seen three zoonotic coronaviruses, with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) causing a pandemic in 2020. Coronaviral non-structural proteins (nsps) form the replication-transcription complex (RTC). Nsp7 and nsp8 interact with and regulate the RNA-dependent RNA-polymerase and other enzymes in the RTC. However, the structural plasticity of nsp7+8 complexes has been under debate. Here, we present the framework of nsp7+8 complex stoichiometry and topology based on native mass spectrometry and complementary biophysical techniques of nsp7+8 complexes from seven coronaviruses in the genera Alpha- and Betacoronavirus including SARS-CoV-2. Their complexes cluster into three groups, which systematically form either heterotrimers or heterotetramers or both, exhibiting distinct topologies. Moreover, even at high protein concentrations, SARS-CoV-2 nsp7+8 consists primarily of heterotetramers. From these results, the different assembly paths can be pinpointed to specific residues and an assembly model proposed.


Asunto(s)
Alphacoronavirus/metabolismo , Betacoronavirus/metabolismo , Proteínas no Estructurales Virales/metabolismo , Secuencia de Aminoácidos , Secuencia Conservada , Reactivos de Enlaces Cruzados/química , Modelos Moleculares , Multimerización de Proteína , Subunidades de Proteína/metabolismo , Dispersión de Radiación , Dispersión del Ángulo Pequeño , Especificidad de la Especie , Proteínas no Estructurales Virales/química , Difracción de Rayos X
8.
Nat Commun ; 12(1): 1607, 2021 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-33707453

RESUMEN

In recognizing the host cellular receptor and mediating fusion of virus and cell membranes, the spike (S) glycoprotein of coronaviruses is the most critical viral protein for cross-species transmission and infection. Here we determined the cryo-EM structures of the spikes from bat (RaTG13) and pangolin (PCoV_GX) coronaviruses, which are closely related to SARS-CoV-2. All three receptor-binding domains (RBDs) of these two spike trimers are in the "down" conformation, indicating they are more prone to adopt the receptor-binding inactive state. However, we found that the PCoV_GX, but not the RaTG13, spike is comparable to the SARS-CoV-2 spike in binding the human ACE2 receptor and supporting pseudovirus cell entry. We further identified critical residues in the RBD underlying different activities of the RaTG13 and PCoV_GX/SARS-CoV-2 spikes. These results collectively indicate that tight RBD-ACE2 binding and efficient RBD conformational sampling are required for the evolution of SARS-CoV-2 to gain highly efficient infection.


Asunto(s)
/virología , Quirópteros/virología , Coronavirus/química , Coronavirus/genética , /química , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Secuencia de Aminoácidos , Animales , /transmisión , Microscopía por Crioelectrón , Evolución Molecular , Interacciones Microbiota-Huesped , Humanos , Modelos Moleculares , Pandemias , Dominios Proteicos , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Glicoproteína de la Espiga del Coronavirus/ultraestructura
9.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652764

RESUMEN

Infection of hosts by morbilliviruses is facilitated by the interaction between viral hemagglutinin (H-protein) and the signaling lymphocytic activation molecule (SLAM). Recently, the functional importance of the n-terminal region of human SLAM as a measles virus receptor was demonstrated. However, the functional roles of this region in the infection process by other morbilliviruses and host range determination remain unknown, partly because this region is highly flexible, which has hampered accurate structure determination of this region by X-ray crystallography. In this study, we analyzed the interaction between the H-protein from canine distemper virus (CDV-H) and SLAMs by a computational chemistry approach. Molecular dynamics simulations and fragment molecular orbital analysis demonstrated that the unique His28 in the N-terminal region of SLAM from Macaca is a key determinant that enables the formation of a stable interaction with CDV-H, providing a basis for CDV infection in Macaca. The computational chemistry approach presented should enable the determination of molecular interactions involving regions of proteins that are difficult to predict from crystal structures because of their high flexibility.


Asunto(s)
Virus del Moquillo Canino/genética , Moquillo/genética , Enfermedades de los Perros/genética , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/genética , Animales , Química Computacional , Moquillo/virología , Virus del Moquillo Canino/patogenicidad , Enfermedades de los Perros/virología , Perros , Humanos , Macaca/virología , Mutación Puntual/genética , Unión Proteica/genética , Receptores Virales/genética , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/química , Familia de Moléculas Señalizadoras de la Activación Linfocitaria/ultraestructura , Especificidad de la Especie , Linfocitos T/virología
10.
Zool Res ; 42(2): 234-240, 2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33709635

RESUMEN

We report on a new amphibian species of the genus Micryletta from Hainan Island, China, based on morphological and molecular analyses. The new species, Micryletta immaculata sp. nov., is diagnosed by a combination of the following morphological characters: medium-sized within genus (SVL 23.3-24.8 mm in males, n=3; 27.7-30.1 mm in females, n=2); dorsum bronze brown to reddish brown in life; dark brown spots and stripes on dorsum and flank absent; flanks largely pigmented with silver white; throat in adult males dark brown; undersides without dark patterns; outer metatarsal tubercle absent; supratympanic fold distinct; webbing between toes basal and poorly developed; tibiotarsal articulation adpressed limb reaching level of tympanum. The new species is divergent from all other congeners based on 16S rRNA gene sequences (3.0%-7.7%). Data on the natural history and male advertisement calls of the new species are provided. Following the IUCN Red List Categories and Criteria, we propose the new species to be listed as Vulnerable B1ab (iii).


Asunto(s)
Anuros/anatomía & histología , Anuros/clasificación , Distribución Animal , Animales , Anuros/fisiología , China , Femenino , Islas , Masculino , Especificidad de la Especie
11.
Zool Res ; 42(2): 182-194, 2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33723929

RESUMEN

Allactaginae is a subfamily of dipodids consisting of four- and five-toed jerboas ( Allactaga, Allactodipus, Orientallactaga, Pygeretmus, Scarturus) found in open habitats of Asia and North Africa. Recent molecular phylogenies have upended our understanding of this group's systematics across taxonomic scales. Here, I used cranial geometric morphometrics to examine variation across 219 specimens of 14 allactagine species ( Allactaga major, A. severtzovi, Orientallactaga balikunica, O. bullata, O. sibirica, Pygeretmus platyurus, P. pumilio, P. shitkovi, Scarturus aralychensis, S. euphraticus, S. hotsoni, S. indicus, S. tetradactylus, S. williamsi) in light of their revised taxonomy. Results showed no significant sexual size or shape dimorphism. Species significantly differed in cranial size and shape both overall and as species pairs. Species identity had a strong effect on both cranial size and shape. Only a small part of cranial shape variation was allometric, with no evidence of unique species allometries, and most specimens fit closely to the common allometric regression vector. Allactaga was the largest, followed by Orientallactaga, Scarturus, and finally Pygeretmus. Principal component 1 (PC1) separated O. bullata+ O. balikunica+ S. hotsoni (with inflated bullae along with reduced zygomatic arches and rostra) from A. major+ A. severtzovi+ O. sibirica (with converse patterns), while PC2 differentiated Orientallactaga (with enlarged cranial bases and rostra along with reduced zygomatic arches and foramina magna) from Scarturus+ Pygeretmus (with the opposite patterns). Clustering based on the unweighted pair group method with arithmetic mean (UPGMA) contained the four genera, but S. hotsoni clustered with O. bullata+ O. balikunica and O. sibirica clustered with A. major+ A. severtzovi, likely due to convergence and allometry, respectively.


Asunto(s)
Roedores/anatomía & histología , Cráneo/anatomía & histología , Distribución Animal , Animales , Filogenia , Roedores/genética , Especificidad de la Especie
12.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672591

RESUMEN

The present study provides new data concerning the chemical characterisation of Physcia mediterranea Nimis, a rare Mediterranean species belonging to the family Physciaceae. The phytochemical screening was carried out using GC-MS, HPLC-ESI-MS-MS, and NMR techniques. Hot extraction of n-hexane was carried out, followed by separation of the part insoluble in methanol: wax (WA-hex), from the part soluble in methanol (ME-hex). GC-MS analysis of the ME-hex part revealed the presence of methylbenzoic acids such as sparassol and atraric acid and a diterpene with a kaurene skeleton which has never been detected before in lichen species. Out of all the compounds identified by HPLC-ESI-MS-MS, sixteen compounds are common between WA-hex and ME-hex. Most are aliphatic fatty acids, phenolic compounds and depsides. The wax part is characterised by the presence of atranorin, a depside of high biological value. Proton 1H and carbon 13C NMR have confirmed its identification. Atranol, chloroatranol (depsides compound), Ffukinanolide (sesquiterpene lactones), leprolomin (diphenyl ether), muronic acid (triterpenes), and ursolic acid (triterpenes) have also been identified in ME-hex. The results suggested that Physcia mediterranea Nimis is a valuable source of bioactive compounds that could be useful for several applications as functional foods, cosmetics, and pharmaceuticals.


Asunto(s)
Líquenes/química , Fitoquímicos/análisis , Estructura Molecular , Especificidad de la Especie
13.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672711

RESUMEN

This study was conducted to develop systems for the identification of four tuna species (skipjack tuna Katsuwonus pelamis, yellowfin tuna Thunnus albacares, bullet tuna Auxis sp. and Atlantic bonito Sarda sp). At first, raw samples of these species and a mix intended as internal control were prepared for the authentication of fish muscle tissue of the genus Thunnus sp., Auxis sp. and Sarda sp. DNA from raw muscle tissue, the mix and samples was extracted with the DNeasy mericon Food Kit (Qiagen GmbH, Hilden, Germany). The concentration and purity of DNA in raw samples were evaluated using a spectrophotometer. Primers and probe sequences were specifically designed to identify the selected species. In addition, primers and a probe for the endogenous 12S rRNA gene were designed to determine the presence of amplifiable fish (especially tuna) DNA in samples. Furthermore, the species specificity of the designed primers and probes was verified in DNA samples of various tuna and bonito species. Limit of detection for the selected species was calculated as well as the coefficient of determination R2 and efficiency of real-time PCR testing was determined. To evaluate the developed real-time PCR methods, 70 commercial tuna products were analysed. The results show that mislabelling of fish products can still be encountered and, moreover, the presence of an additional species can be identified.


Asunto(s)
ADN/genética , Productos Pesqueros/análisis , Músculos/química , Animales , Especificidad de la Especie , Atún
14.
Food Chem ; 349: 129173, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33582543

RESUMEN

Change in metabolites and volatiles during yellowing process in six rice cultivars was analyzed. Based on the yellowness, the study indicated Japonica was more prone to yellowing than Indica rice. Metabonomics analysis showed most differential metabolites were up-regulated, in which pathways of flavone and flavonol biosynthesis were significantly enriched following the yellowing process. Meanwhile, 54 differential metabolites were overlapped in six comparative groups, which is characterized by commonly-shared metabolic regulation pathway in each rice. Phenylalanine content was increased, followed by the enhanced phenylpropanoids formation, showing transformation between primary and secondary metabolites during yellowing process. Furthermore, 43 volatile compounds were identified, and the yellowed rice had more volatiles, including ketones, alcohols, esters and hydrocarbons, suggesting a positive correlation with the yellowing. Compounds 6-methyl-5-hepten-2-one and 6,10,14-trimethyl-2-pentadecanone were increased steadily during yellowing process, which may be applied for monitoring rice yellowing progress. This investigation provides further insight for revealing rice yellowing mechanism.


Asunto(s)
Metabolómica , Oryza/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Color , Oryza/clasificación , Metabolismo Secundario , Especificidad de la Especie
15.
Toxicol Lett ; 341: 94-106, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33539969

RESUMEN

Enzymatic conjugation of glutathione (GSH) to trichloroethylene (TCE) followed by catabolism to the corresponding cysteine-conjugate, S-(dichlorovinyl)-L-cysteine (DCVC), and subsequent bioactivation by renal cysteine conjugate beta-lyases is considered to play an important role in the nephrotoxic effects observed in TCE-exposed rat and human. In this study, it is shown for the first time that three regioisomers of GSH-conjugates of TCE are formed by rat and human liver fractions, namely S-(1,2-trans-dichlorovinyl)-glutathione (1,2-trans-DCVG), S-(1,2-cis-dichlorovinyl)-glutathione (1,2-cis-DCVG) and S-(2,2-dichlorovinyl)-glutathione (2,2-DCVG). In incubations of TCE with rat liver fractions their amounts decreased in order of 1,2-cis-DCVG > 1,2-trans-DCVG > 2,2-DCVG. Human liver cytosol showed a more than 10-fold lower activity of GSH-conjugation, with amounts of regioisomers decreasing in order 2,2-DCVG > 1,2-trans-DCVG > 1,2-cis-DCVG. Incubations with recombinant human GSTs suggest that GSTA1-1 and GSTA2-2 play the most important role in human liver cytosol. GSTP1-1, which produces regioisomers in order 1,2-trans-DCVG > 2,2-cis-DCVG > 1,2-cis-DCVG, is likely to contribute to extrahepatic GSH-conjugation of TCE. Analysis of the products formed by a beta-lyase mimetic model showed that both 1,2-trans-DCVC and 1,2-cis-DCVC are converted to reactive products that form cross-links between the model nucleophile 4-(4-nitrobenzyl)-pyridine (NBP) and thiol-species. No NBP-alkylation was observed with 2,2-DCVC corresponding to its low cytotoxicity and mutagenicity. The lower activity of GSH-conjugation of TCE by human liver fractions, in combination with the lower fraction of potential nephrotoxic and mutagenic 1,2-DCVG-isomers, suggest that humans are at much lower risk for TCE-associated nephrotoxic effects than rats.


Asunto(s)
Glutatión Transferasa/metabolismo , Glutatión/análogos & derivados , Glutatión/metabolismo , Tricloroetileno/farmacología , Animales , Cromatografía Liquida , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Glutatión Transferasa/genética , Humanos , Hígado , Masculino , Estructura Molecular , Ratas , Ratas Wistar , Proteínas Recombinantes , Solventes/farmacología , Especificidad de la Especie
16.
Exp Parasitol ; 223: 108081, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33549536

RESUMEN

Artificial breeding of small yellow croaker (Larimichthys polyactis) was recently achieved, providing a bright future for its commercial farming. In May 2019, a disease outbreak occurred among small yellow croakers in an aquaculture farm near Xiangshan Bay, charactering by white spots spotted on the surface of fish skin, gills and fins. The parasite was preliminarily identified as Cryptocaryon irritans based on morphological feature of the parasite and the symptoms on fish. However, the previously published specific primer pairs failed to confirm the existence of C. iriitans. Six nucleotides mismatches were discovered after mapping specific forward primer back to targeted gene. Therefore, an updated PCR specific primer was developed within the 9th highly variable region of 18S rRNA gene and conserved in all C. irritans sequences available in GenBank database. The specificity was verified in silico by Primer-BLAST against GenBank nucleotide. Laboratory cultured ciliates (Mesanophrys, Pseudokeronopsis and Uronema) as well as natural microbial community samples collected from sea water and river water was used as negative control to verify the specificity of the primer in situ. Besides, tank transfer method was used to evaluate the treatment of the parasite infection. By tank transfer method, 2.00 ± 0.61 out of 10 fish that already sever infected were successfully survived after 8 days treatment, meanwhile the control group died out at d 6. More loss to the treatment group during first five days was observed and may attribute to the combined effect from infection and stress the recent domesticated fish suffered during rotation. Therefore, tank transfer method was also effective to prevent small yellow croaker from further infection, however the loss of the small yellow croaker suffered from stress during rotation also needs to be carefully concerned. In conclusion, this study reported the first diagnose of C. irritans infection on small yellow croaker, provided updated specific primer to detect C. irritans infection on fish body and reported the effect of tank transfer on small yellow croaker treatment.


Asunto(s)
Infecciones por Cilióforos/veterinaria , Cilióforos/aislamiento & purificación , Enfermedades de los Peces/parasitología , Perciformes/parasitología , Aletas de Animales/parasitología , Aletas de Animales/patología , Animales , China/epidemiología , Cilióforos/clasificación , Cilióforos/genética , Infecciones por Cilióforos/diagnóstico , Infecciones por Cilióforos/epidemiología , Infecciones por Cilióforos/parasitología , Brotes de Enfermedades/veterinaria , Enfermedades de los Peces/diagnóstico , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/terapia , Explotaciones Pesqueras , Branquias/parasitología , Branquias/patología , Músculo Esquelético/parasitología , Músculo Esquelético/patología , Filogenia , ARN Ribosómico 18S/genética , Piel/parasitología , Piel/patología , Especificidad de la Especie
17.
Zoolog Sci ; 38(1): 45-50, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33639717

RESUMEN

In medaka fishes, the family Adrianichthyidae, tropical species are known to be sexually more dimorphic than temperate species. If this reflects that tropical species are exposed to stronger sexual-selection pressures than temperate species, mating behaviors may also differ between tropical and temperate species. Our mating experiments revealed that males of Oryzias woworae, a tropical species of the family, perform "chasing" another male more frequently than males of O. sakaizumii, a temperate congener, and that male-male "combats" of O. woworae tended to be followed by chasing compared with combats of O. sakaizumii males, indicating that O. woworae males are more aggressive in male-male interactions than O. sakaizumii males. Males of O. woworae also performed "approaching" a female and "mating dance" more frequently than O. sakaizumii males, indicating that O. woworae males are also more active in courting females. Males of O. sakaizumii often omitted "mating dance" in their mating sequences, supporting this view. Moreover, O. woworae females tended to reject male "wrapping", an attempt for fertilization, more frequently than O. sakaizumii females, suggesting that O. woworae females are choosier in mating than O. sakaizumii females. These findings are concordant with the view that O. woworae is exposed to stronger sexual-selection pressures than O. sakaizumii.


Asunto(s)
Agresión , Oryzias/fisiología , Conducta Sexual Animal , Animales , Femenino , Masculino , Especificidad de la Especie
18.
Zoolog Sci ; 38(1): 90-102, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33639723

RESUMEN

Two new species of the cockroach genus Eucorydia Hebard, 1929 from the Nansei Islands in Southwest Japan were compared to two closely related congeners, Eucorydia yasumatsui Asahina, 1971 and Eucorydia dasytoides (Walker, 1868). Eucorydia donanensis Yanagisawa, Sakamaki, and Shimano sp. nov. from Yonaguni-jima Island was characterized by an overall length of 12.5-14.5 mm in males. The dorsal side of the male abdomen was entirely dark purple and there was an obscure orange band running down the middle of the tegmen. Eucorydia tokaraensis Yanagisawa, Sakamaki, and Shimano sp. nov. was characterized by an overall length of 12.0-13.0 mm in males and a distinct orange band running down the middle of the tegmen. Eucorydia yasumatsui, E. donanensis, E. tokaraensis and the zonata population of E. dasytoides were divided into four lineages in a maximum-likelihood tree generated from a dataset concatenated from five (two nuclear, 28S rRNA, histone H3, and three mitochondrial, COII, 12S rRNA, 16S rRNA) genes. We recognized the three Japanese lineages E. yasumatsui, E. donanensis, and E. tokaraensis as distinct species, which were also supported by the pairwise genetic distances (5.4-7.8%, K2P) of the COI sequences. Morphometric analysis was performed on the genitalia. A principal component analysis plot revealed that the sizes of the genitalia in the three Japanese species were similar to each other and smaller than that of the zonata population of E. dasytoides. The analysis also revealed that the three Japanese species were distinguished from each other by combinations of the sizes of L3 and L7 sclerites and the shape of R2 sclerite, with some overlapping exceptions.


Asunto(s)
Cucarachas/anatomía & histología , Cucarachas/clasificación , Animales , Cucarachas/genética , Femenino , Genitales Masculinos/anatomía & histología , Japón , Masculino , Especificidad de la Especie
19.
Eur J Protistol ; 78: 125766, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33548733

RESUMEN

The morphology, morphogenesis and molecular phylogeny of a new saline soil hypotrich ciliate, Uroleptoides salina nov. spec., discovered from China, was investigated. The new species is characterized as follows: body 150-215 × 40-50 µm in vivo, slender and highly flexible; usually four ellipsoidal macronuclear nodules; contractile vacuole absent; cortical granules absent; endosymbiotic algae present; amphisiellid median cirral row consists of 14-25 cirri and terminates about 47% down length of body; usually three buccal cirri and 3-13 cirri left of anterior portion of amphisiellid median cirral row; 3-5 transverse cirri. Morphogenesis during binary fission is characterized by: (1) the parental adoral zone of membranelles is retained completely, parental paroral contributes to the formation of the undulating membranes anlage for the proter; (2) the oral primordium of the opisthe is formed apokinetally; and (3) the amphisiellid median cirral row is formed from two anlagen. Phylogenetic analyses based on SSU rDNA sequence data show that Uroleptoides salina nov. spec. has a close relationship with its morphologically similar species, U. longiseries, U. magnigranulosus, Orthamphisiella breviseries, and Parabistichella variabilis.


Asunto(s)
Hypotrichida/clasificación , Filogenia , Suelo/parasitología , Hypotrichida/citología , Hypotrichida/genética , ARN Ribosómico 18S/genética , Especificidad de la Especie
20.
Eur J Protistol ; 78: 125769, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33549969

RESUMEN

A little-known haptorid ciliate, Helicoprorodon multinucleatum Dragesco, 1960, was found in a sandy beach at Qingdao, China. Its morphology was studied based on microscopic observations of live and protargol-stained specimens and morphometrics, and the phylogeny was analyzed using SSU rRNA gene sequences. Helicoprorodon multinucleatum is characterized by the combination of the following features: (i) a very narrowly worm-like body with a size of about 300-1500 µm × 30-60 µm in vivo, and two circles of horn-like protuberances around the head; (ii) 50-160 spherical macronuclear nodules scattered throughout the body; (iii) rod-shaped, 10-50 µm long extrusomes gathered into several bunches, which are randomly distributed beneath pellicle; and (iv) 42-88 somatic kineties, including four oralized kineties and two dorsal brush rows. Phylogenetic analyses reveal that both the family Helicoprorodontidae and the genus Helicoprorodon might be monophyletic. In addition, we provide an illustrated key to the species and the geographical distribution of the genus Helicoprorodon.


Asunto(s)
Cilióforos/clasificación , Filogenia , China , Cilióforos/citología , Cilióforos/genética , ADN Protozoario/genética , ARN Ribosómico 18S/genética , Especificidad de la Especie
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