Search Results (19)

Between March and August 2024, three species of Fundulus topminnows, including two northern studfish, Fundulus catenatus, six blackspotted topminnows, Fundulus olivaceus, and eleven blackstriped topminnows, Fundulus notatus, were collected from various Ouachita River drainage watersheds in Arkansas, USA. They were examined for myxozoans by having their gill, gallbladder, fins, integument, mesenteries, musculature, and other major organs examined. The mesenteries of two (33%) F. olivaceus from Town Creek (Fulton County, Arkansas, USA) were infected with a new myxozoan, Myxobolus storeri sp. n. Molecular data consisted of a 1726 base pair sequence of the partial small subunit ribosomal RNA gene for M. storeri sp. n. Histologically, plasmodia were limited to mesenteric adipose and hepatic parenchyma, causing slight compression of neighboring tissue but producing no associated inflammatory response in the examined histosections. This is the first time a myxozoan has been described from F. olivaceus and is the seventh species recorded from any member of the fish family Fundulidae. Full article

In the present study, we compared the genetic variability of fragments from the internal transcribed spacer region (ITS) and the small subunit ribosomal DNA (SSUrDNA) as nuclear markers, in contrast with the ribosomal protein large two (rpl2) loci, placed in the mitochondrion-related organelles (MROs) within and among human fecal samples with Blastocystis. Samples were analyzed using polymerase chain reaction (PCR)-sequencing, phylogenies, and genetics of population structure analyses were performed. In total, 96 sequences were analyzed, i.e., 33 of SSUrDNA, 35 of rpl2, and 28 of ITS. Only three subtypes (STs) were identified, i.e., ST1 (11.4%), ST2 (28.6%), and ST3 (60%); in all cases, kappa indexes were 1, meaning a perfect agreement among ST assignations. The topologies of phylogenetic inferences were similar among them, clustering to each ST in its specific cluster; discrepancies between phylogeny and assignment of STs were not observed. The STRUCTURE v2.3.4 software assigned three subpopulations corresponding to the STs 1–3, respectively. The population indices were consistent with those previously reported by other groups. Our results suggest the potential use of the ITS and rpl2 genes as molecular markers for Blastocystis subtyping as an alternative approach for the study of the genetic diversity observed within and between human isolates of this microorganism. Full article

During a survey of fungi on Wurfbainia villosa in Guangdong Province, China, three novel species, Periconia endophytica, P. yangjiangensis, and P. wurfbainiae, belonging to Periconiaceae in Pleosporales, Dothideomycetes are proposed based on morphological and phylogenetic evidence. Periconia endophytica was isolated from the healthy leaves of W. villosa, while P. yangjiangensis and P. wurfbainiae were obtained from the dead stems of the same host. Notably, holomorphs were observed in P. wurfbainiae. The morphological characteristics of the novel taxa are compared with closely related species within Periconia. Illustrations, morphological descriptions, and phylogenetic analyses are provided for the novel taxa. Multilocus phylogeny of the combined internal transcribed spacer (ITS), large subunit nuclear rDNA (LSU), small subunit nuclear ribosomal rDNA (SSU), and partial translation elongation factor 1–α (tef1-α) regions supported the establishment of three new species. Furthermore, the taxa clustering in Periconia, Flavomyces fulophazii, and Sporidesmium tengii, are discussed for further investigation of their taxonomic placements. Full article

Microsporidia are natural pathogens of arthropods and have been used as biological control against insect pests. In the United States, efforts to control the invasive Red Imported Fire Ant, Solenopsis invicta, and Black Imported Fire Ant, Solenopsis richteri, have included the use of the microsporidium, Kneallhazia solenopsae. However, there is limited information about the genetic differences among the microsporidian variants found in S. invicta and in S. richteri. In this study, we assessed the prevalence and genetic diversity of K. solenopsae in native populations of S. richteri in Argentina (South America). Additionally, we examined the social parasitic ant, Solenopsis daguerrei, which is found in some S. richteri nests, for the presence of this microsporidium. The survey of 219 S. richteri nests revealed K. solenopsae infections in all five sites analyzed, with 28 colonies (12.8%) positive for the microsporidium. Among the 180 S. daguerrei individuals collected, seven ants (3.9%) from three sites tested positive for K. solenopsae. Phylogenetic analyses of the microsporidian variants present in S. richteri and S. daguerrei based on partial small subunit ribosomal gene sequences (SSU rRNA) showed that both ant species shared the same variant, which is different from the ones found in S. invicta. Further studies are needed to determine the pathogenicity of genetically different K. solenopsae variants among Solenopsis species. Full article

Three species of the genus Phyllopodopsyllus T. Scott, 1906 (Copepoda: Harpacticoida: Tetragonicipitidae) were reported from the intertidal sand of Jeju Island and Busan in Korea, Phyllopdopsyllus kitazimai Karanovic, 2017, Phyllopodopsyllus saywakimi sp. nov. and Phyllopodopsyllus similis sp. nov. The latter two were described here. Phyllopodopsyllus saywakimi sp. nov. collected from only Udo, Jeju is similar to a Pacific species from Costa Rica, Phyllopodopsyllus ancylus Mielke, 1992. However, P. saywakimi sp. nov. differs from the Costa Rica species in the body size, the number of armatures on the antenna, the length ratio of endo- and exopod of the mandible, and the chaetotaxy of the fifth female pereiopod and the sixth male pereiopod. The second new species, P. similis sp. nov., found in Busan and several localities of Jeju, significantly resembles the species complex related to Phyllopodopsyllus aegypticus Nicholls, 1944, which is widely distributed in the Indian, Pacific, and Atlantic oceans. P. similis sp. nov. can be distinguished from the P. aegypticus complex by the body size, the shape of the rostrum, the type of armatures, the length ratio of rami and armatures, and the chaetotaxy of the female P5. In addition to the species descriptions, partial fragments of small and large subunit ribosomal RNA genes, cytochrome b, and cytochrome c oxidase subunit I were provided. Using molecular markers, a phylogenetic analysis was also performed to estimate the relationships among the three Korean species of Phyllopodopsyllus for the first time. Full article

HAX1 is a human protein with no known homologues or structural domains. Mutations in the HAX1 gene cause severe congenital neutropenia through mechanisms that are poorly understood. Previous studies reported the RNA-binding capacity of HAX1, but the role of this binding in physiology and pathology remains unexplained. Here, we report the transcriptome-wide characterization of HAX1 RNA targets using RIP-seq and CRAC, indicating that HAX1 binds transcripts involved in translation, ribosome biogenesis, and rRNA processing. Using CRISPR knockouts, we find that HAX1 RNA targets partially overlap with transcripts downregulated in HAX1 KO, implying a role in mRNA stabilization. Gene ontology analysis demonstrated that genes differentially expressed in HAX1 KO (including genes involved in ribosome biogenesis and translation) are also enriched in a subset of genes whose expression correlates with HAX1 expression in four analyzed neoplasms. The functional connection to ribosome biogenesis was also demonstrated by gradient sedimentation ribosome profiles, which revealed differences in the small subunit:monosome ratio in HAX1 WT/KO. We speculate that changes in HAX1 expression may be important for the etiology of HAX1-linked diseases through dysregulation of translation. Full article

Calla lily (Zantedeschia albomaculata (Hook.) Baill.) is an herbaceous or semi-evergreen perennial grown from rhizomes. It is commonly named “Spotted Arum”. Ribosomal RNAs (rRNAs) are found in all known organisms and are known for being functionally equivalent in all of them. A completely new in vitro culture protocol was applied to Z. albomaculata with two hormones, 6-Benzylaminopurine (BAP) and kinetin, to obtain full growth and multiplication. Due to their highly conserved sequences, the analysis of small-subunit rRNAs (16S–18S rRNAs) can provide precise statistical evaluation of a wide variety of phylogenetic connections. As a result, the plant’s 18S rRNA gene allowed for identification and partial sequencing. Also, the traditional floral method and the novel application technique for identification were applied to Z. albomaculata. In this paper we systemically describe the structural strategies of the plant’s adaptation to the surroundings at the morphological, physiological, and anatomical scale. Most the essential oils and fatty acids found in Z. albomaculata are omega fatty acids, octadecenoic acid, linoleic acid, and palmitic acid. All these fatty acids have industrial, medicinal, and pharmaceutical applications. The significant findings are the spadix sheathing leaves, and the precipitation of raphides calcium oxalate. The mitotic index showing the division activity was recorded, and it was 17.4%. The antimicrobial activity of Z. albomaculata ethanol extract was performed via the well diffusion method. This extract has shown high activity against Escherichia coli and Pseudomonas aeruginosa, compared to its lower activity against Bacillus cereus. By defining these characteristics and in vitro culture conditions, we will be able to acclimatize the plant in greenhouses, and then transfer it to the open field. The findings of this work identified the general characteristics of Zantedeschia albomaculata as an ornamental and medicinal plant in order to acclimatize this plant for cultivation in the Mediterranean climate. Full article

The genus Exophiala is an anamorphic ascomycete fungus in the family Herpotrichiellaceae of the order Chaetothyriales. Exophiala species have been classified as polymorphic black yeast-like fungi. Prior to this study, 63 species had been validated, published, and accepted into this genus. Exophiala species are known to be distributed worldwide and have been isolated in various habitats around the world. Several Exophiala species have been identified as potential agents of human and animal mycoses. However, in some studies, Exophiala species have been used in agriculture and biotechnological applications. Here, we provide a brief review of the diversity, distribution, and taxonomy of Exophiala through an overview of the recently published literature. Moreover, four new Exophiala species were isolated from rocks that were collected from natural forests located in northern Thailand. Herein, we introduce these species as E. lamphunensis, E. lapidea, E. saxicola, and E. siamensis. The identification of these species was based on a combination of morphological characteristics and molecular analyses. Multi-gene phylogenetic analyses of a combination of the internal transcribed spacer (ITS) and small subunit (nrSSU) of ribosomal DNA, along with the translation elongation factor (tef), partial β-tubulin (tub), and actin (act) genes support that these four new species are distinct from previously known species of Exophiala. A full description, illustrations, and a phylogenetic tree showing the position of four new species are provided. Full article

The cultivation of morel mushrooms (Morchella spp.) outdoors or in controlled indoor systems is a relatively new practice, and infections are beginning to be observed. Infection of indoor-cultivated Morchella rufobrunnea initials (primordia) occurred at our research facilities in Israel. The mushroom initials turned brown, were covered with a dense white mycelium of a foreign fungus and were disintegrated soon after. The isolation of a fungal contaminant from the infected mushroom revealed small colonies with a pinkish spore zone on potato dextrose agar medium. Molecular identification using partial large subunit 28S ribosomal DNA and rRNA internal transcribed spacer sequences identified the fungus as Purpureocillium lilacinum. Inoculation of Morchella colony on agar plat with the isolated fungus caused browning and inhibition of mycelial growth. Inoculation of a healthy primordium with P. lilacinum spores resulted in its browning and deterioration. This is the first report of an infection of indoor-cultivated mushroom and the first showing P. lilacinum as a pathogen of morels. Full article

Pin nematodes (Paratylenchus spp.) currently comprise 132 species of polyphagous plant ectoparasites with at least seven species that are plant pathogenic emphasizing the need for correct identification to establish an appropriate management strategy. Sequences of highly conserved regions of ribosomal and mitochondrial RNA genes are a powerful species-level diagnostic tool within Tylenchulidae. A nematological survey was conducted from 2019 to 2021 in commercial vineyards distributed in four major wine-producing regions in the Central and South Portugal. Nine populations of Paratylenchus spp. were isolated from the rhizosphere of grapevines that were characterized from morphological data and molecular phylogenetic analysis using two rRNA genes (D2–D3 expansion segments of the 28S, and partial 18S) and a region partial of the COI mtRNA gene. Contrasting morphological hypotheses with molecular data provided rapid detection of six species, specifically P. goodeyi, P. hamatus, P. pedrami, P. tenicaudatus, P. variabilis, and P. veruculatus. Bayesian inference (BI) phylogenetic trees for these molecular markers established phylogenetic relationships underscore the importance of using genomic and molecular phylogenetic data for accurate pin nematode identification at the species level. To our knowledge, this is the first report of Paratylenchus spp. in Portugal, extending the geographical distribution of these species in the Mediterranean Basin, and the first record of P. goodeyi, P. pedrami, P.variabilis, P. veruculatus and P. tenicaudatus parasitizing grapevine. Full article

Two new Russula species, R. subbrevipes and R. callainomarginis, from China are described based on morphological and molecular characteristics. Russula subbrevipes has thus far only been found in southwestern China at altitudes of higher than 3400 m and is characterized by a yellow ochre pileal surface, glabrous or tomentose stipe, fruity odor, subglobose to ellipsoid basidiospores, isolated or partially connected warts and pleurocystidia with a cap appendage. Russula callainomarginis is characterized by a cream to white pileus, light turquoise lamellae margin, spongy stipe, light turquoise zone on the top of the stipe, pungent odor, globose to ellipsoid basidiospores and dominant isolated warts. The phylogenetic tree of Russula was constructed with multi-gene sequences, including the internal transcribed spacer regions (ITS), the ribosomal large subunit (nrLSU), the small subunit of the mitochondrial rRNA gene (mtSSU) and the second largest subunit of RNA polymerase II (RPB2). The results show that both R. subbrevipes and R. callainomarginis represent new lineages in Russula subg. Brevipes. Description and illustration of the two new species are presented. Full article

Blastocystis is a common food- and water-borne intestinal protist parasite of humans and many other animals. Blastocystis comprises multiple subtypes (STs) based on variability within the small subunit ribosomal (SSU rRNA) RNA gene. Though full-length reference sequences of the SSU rRNA gene are a current requirement to name a novel Blastocystis subtype, full-length reference sequences are not currently available for all subtypes. In the present study, Oxford Nanopore MinION long-read sequencing was employed to generate full-length SSU rRNA sequences for seven new Blastocystis subtypes for which no full-length references currently exist: ST21, ST23, ST24, ST25, ST26, ST27, and ST28. Phylogenetic analyses and pairwise distance matrixes were used to compare full-length and partial sequences of the two regions that are most commonly used for subtyping. Analyses included Blastocystis nucleotide sequences obtained in this study (ST21 and ST23–ST28) and existing subtypes for which full-length reference sequences were available (ST1–ST17 and ST29). The relationships and sequence variance between new and existing subtypes observed in analyses of different portions of the SSU rRNA gene are discussed. The full-length SSU rRNA reference sequences generated in this study provide essential new data to study and understand the relationships between the genetic complexity of Blastocystis and its host specificity, pathogenicity, and epidemiology. Full article

Evidence of sarcocystid infection was investigated in samples of 16 penguins (Spheniscus. magellanicus), four Dominican gulls (Larus dominicanus) and two Chilean skuas (Stercorarius chilensis) found in Madalenas Islands, Chile, in 2017. Samples of skeletal muscle, cardiac muscle and brain from all birds were screened by a pan-sarcocystid nested-PCR targeting a short fragment of the gene encoding the small ribosomal unit (nPCR-18Sa). The only two positive samples by nPCR-18Sa, both from skuas, were tested by a nested-PCR directed to the internal transcribed spacer 1 (nPCR-ITS1), also a pan-sarcocystidae nested-PCR, and to a nested-PCR directed to the B1 gene (nPCR-B1), for the exclusive detection of Toxoplasma gondii. The two nPCR-18Sa-positive samples were nPCR-ITS1-positive and nPCR-B1-negative. The nPCR-ITS1 nucleotide sequences from the two skuas, which were identical to each other, were revealed closely related to homologous sequences of Sarcocystis halieti, species found in seabirds of northern hemisphere. Larger fragments of genes encoding 18S and partial sequences of genes coding for cytochrome oxidase subunit 1 were also analyzed, corroborating ITS1 data. The haplotypes found in the skuas are unprecedent and closely related to species that use birds as the definitive host. Further studies need to be carried out to detect, identify and isolate this parasite to understand the epidemiology of the infection and its impact on the health of marine fauna. Full article

Diabetes mellitus (DM) is a major global public health problem with an increasing prevalence. DM increases the risk of infections caused by bacteria, fungi, viruses, and parasites. We examined the prevalence, subtypes, and risk factors of Blastocystis infection in patients with and without DM in central Thailand. Stool samples and questionnaires were obtained from 130 people in the DM group and 100 people in the non-DM group. Blastocystis infection was identified via a nested polymerase chain reaction and subtyped via sequencing of the partial small-subunit ribosomal RNA (SSU rRNA) gene. Analysis of potential risk factors was conducted via binary logistic regression. The overall prevalence of Blastocystis infection was 10.8%, including rates of 9% and 12.3% in the non-DM and DM groups, respectively. The most prevalent subtype was ST3, followed by ST1, and ST4. Factors that potentially increased the risk of Blastocystis infection include patients being >65 years old, the presence of DM, a DM duration of ≥10 years, a low level of education, and animal ownership. In conclusion, this is the first study of Blastocystis infection in DM, and a high prevalence was found among this population. Therefore, health education promoting sanitation and hygiene is necessary to reduce and prevent infection in the community. Full article

Leaves of Arabidopsis develop from a shoot apical meristem grow along three (proximal–distal, adaxial–abaxial, and medial–lateral) axes and form a flat symmetric architecture. ASYMMETRIC LEAVES2 (AS2), a key regulator for leaf adaxial–abaxial partitioning, encodes a plant-specific nuclear protein and directly represses the abaxial-determining gene ETTIN/AUXIN RESPONSE FACTOR3 (ETT/ARF3). How AS2 could act as a critical regulator, however, has yet to be demonstrated, although it might play an epigenetic role. Here, we summarize the current understandings of the genetic, molecular, and cellular functions of AS2. A characteristic genetic feature of AS2 is the presence of a number of (about 60) modifier genes, mutations of which enhance the leaf abnormalities of as2. Although genes for proteins that are involved in diverse cellular processes are known as modifiers, it has recently become clear that many modifier proteins, such as NUCLEOLIN1 (NUC1) and RNA HELICASE10 (RH10), are localized in the nucleolus. Some modifiers including ribosomal proteins are also members of the small subunit processome (SSUP). In addition, AS2 forms perinucleolar bodies partially colocalizing with chromocenters that include the condensed inactive 45S ribosomal RNA genes. AS2 participates in maintaining CpG methylation in specific exons of ETT/ARF3. NUC1 and RH10 genes are also involved in maintaining the CpG methylation levels and repressing ETT/ARF3 transcript levels. AS2 and nucleolus-localizing modifiers might cooperatively repress ETT/ARF3 to develop symmetric flat leaves. These results raise the possibility of a nucleolus-related epigenetic repression system operating for developmental genes unique to plants and predict that AS2 could be a molecule with novel functions that cannot be explained by the conventional concept of transcription factors. Full article