Coccidian parasites in the endangered Forest Musk Deer (Moschus berezovskii) in China, with the description of six new species of Eimeria (Apicomplexa: Eimeriidae)

We examined 674 fresh fecal samples from forest musk deer (Moschus berezovskii Flerov) in Sichuan and Shaanxi Provinces, China, for coccidian oocysts and 65% were infected with Eimeria spp. Previously, only four Eimeria species were known from Moschus spp. Here we describe six new Eimeria species. Eimeria aquae n. sp., in 38% deer, has ovoidal oocysts, 32.0 × 23.0 μm, micropyle (M) and scattered polar granules (PGs) of various sizes are present, sometimes oocyst residuum (OR) is present; ovoidal sporocysts, 14.1 × 7.5 μm, with Stieda body (SB) and sporocyst residuum (SR). Eimeria dolichocystis n. sp., in 11% deer; cylindroidal oocysts, 36.6 × 18.9, with a M, 1 PG and OR; ovoidal sporocysts, 13.9 × 7.7, with SB and SR. Eimeria fengxianensis n. sp., in 7% deer; ovoidal oocysts, 36.3 × 25.2, a M and PGs present but OR absent; ovoidal sporocysts, 13.9 × 7.3, with SB and SR. Eimeria helini n. sp. in 24% deer; subspheroidal oocysts, 27.0 × 24.1, OR and PGs often present, but M absent; ovoidal sporocysts, 13.5 × 7.7, with SB and SR. Eimeria kaii n. sp. in 26% deer; ovoidal oocysts, 33.2 × 20.7, M and PGs present, but OR absent; ovoidal sporocysts, 14.4 × 7.5, with SB and SR. Eimeria oocylindrica n. sp., in 17% deer; cylindroidal oocysts, 36.0 × 21.4, M and 1-2 PGs present but OR absent; ovoidal sporocysts, 13.8 × 7.7, with SB and SR. Eimeria dujiangyanensis n. nom. is proposed to replace E. moschus Sha, Zhang, Cai, Wang & Liu, 1994, a junior homonym of E. moschus Matschoulsky, 1947.

Eimeria ferreirai n. sp. (Chromista: Miozoa: Eimeriidae) from doves Leptotila spp. (Columbiformes: Columbidae) from Brazil

The doves and pigeons constitute a taxonomic group (Columbiformes: Columbidae) of granivorous and frugivorous birds with a worldwide distribution. The current work aims to describe morphologically and molecularly a new protozoan from white-tipped doves Leptotila verreauxi Bonaparte, 1855 and grey-fronted doves Leptotila rufaxilla (Richard & Bernard, 1792) in Southeastern Brazil. Eimeria ferreirai n. sp. has oocysts that are sub-spherical to ellipsoidal, 21.4 × 18.8 μm, with smooth, bilayered wall, ~1.6 μm thick. Micropyle present. Oocyst residuum absent, but one to two polar granules are present. Sporocysts are elongate ovoidal to boomerang-shaped, 13.4 × 6.9 μm. Stieda body triangular to lozengal. Sporocyst residuum is composed of granules of different sizes. Sporozoites are vermiform with refractile body and nucleus. Sequencing of the mitochondrial cytochrome c oxidase subunit 1 (COI) gene and the subsequent phylogenetic molecular comparisons supported the description of the new species, since the maximum similarity was 90-95% with eimeriid species of Columbiformes, Anseriformes, Galliformes and Passeriformes. Thus, this is the first coccidian species reported from Leptotila spp. and the twentieth description of an eimerian from Columbiformes in the World.

Protein components of ribonucleoprotein granules from Drosophila germ cells oligomerize and show distinct spatial organization during germline development

The assembly of large RNA-protein granules occurs in germ cells of many animals and these germ granules have provided a paradigm to study structure-functional aspects of similar structures in different cells. Germ granules in Drosophila oocyte’s posterior pole (polar granules) are composed of RNA, in the form of homotypic clusters, and proteins required for germline development. In the granules, Piwi protein Aubergine binds to a scaffold protein Tudor, which contains 11 Tudor domains. Using a super-resolution microscopy, we show that surprisingly, Aubergine and Tudor form distinct clusters within the same polar granules in early Drosophila embryos. These clusters partially overlap and, after germ cells form, they transition into spherical granules with the structural organization unexpected from these interacting proteins: Aubergine shell around the Tudor core. Consistent with the formation of distinct clusters, we show that Aubergine forms homo-oligomers and using all purified Tudor domains, we demonstrate that multiple domains, distributed along the entire Tudor structure, interact with Aubergine. Our data suggest that in polar granules, Aubergine and Tudor are assembled into distinct phases, partially mixed at their “interaction hubs”, and that association of distinct protein clusters may be an evolutionarily conserved mechanism for the assembly of germ granules.

Transcriptomic and functional analysis of the oosome, a unique form of germ plasm in the wasp Nasonia vitripennis

Background The oosome is the germline determinant in the wasp Nasonia vitripennis and is homologous to the polar granules of Drosophila. Despite a common evolutionary origin and developmental role, the oosome is morphologically quite distinct from polar granules. It is a solid sphere that migrates within the cytoplasm before budding out and forming pole cells. Results To gain an understanding of both the molecular basis of oosome development and the conserved essential features of germ plasm, we quantified and compared transcript levels between embryo fragments that contained the oosome and those that did not. The identity of the differentially localized transcripts indicated that Nasonia uses a distinct set of molecules to carry out conserved germ plasm functions. In addition, functional testing of a sample of localized transcripts revealed potentially novel mechanisms of ribonucleoprotein assembly and pole cell cellularization in the wasp. Conclusions Our results demonstrate that the composition of germ plasm varies significantly within Holometabola, as very few mRNAs share localization to the oosome and polar granules. Some of this variability appears to be related to the unique properties of the oosome relative to the polar granules in Drosophila, and some may be related to differences in pole formation between species. This work will serve as the basis for further investigation into the patterns of germline determinant evolution among insects, the molecular basis of the unique properties of the oosome, and the incorporation of novel components into developmental networks.

Isospora brasilsatoae n. sp. (Apicomplexa: Eimeriidae) from thrushes Turdus spp. (Passeriformes: Turdidae) from Brazil

A new species of coccidia (Protozoa: Apicomplexa: Eimeriidae) found parasitizing the yellow-legged thrush Turdus flavipes (Vieillot, 1818), the pale-breasted thrush Turdus leucomelas Vieillot, 1818 and the creamy-bellied thrush Turdus amaurochalinus Cabanis, 1850 in Southeastern Brazil is described. Isospora brasilsatoae n. sp. has oocysts that are ovoidal to pyriform, 26.8 × 21.1 μm, with smooth, bilayered wall, ~1.6 μm thick. Micropyle present. Oocyst residuum absent, but one to three polar granules are present. Sporocysts are elongate ovoidal, 18.1 × 10.5 μm. Stieda body knob-like and sub-Stieda body trapezoidal. Sporocyst residuum is composed of granules that appear to be membrane-bounded. Sporozoites are vermiform with refractile bodies and striations. This is the ninth description of an Isospora sp. parasitizing a New World thrush.

Eimeria psittacarae n. sp. (Apicomplexa: Eimeiriidae) from white-eyed parakeets Psittacara leucophthalmus (Müller, 1776) (Psittaciformes: Psittacidae) kept for rehabilitation and reintroduction in the Parque Nacional da Serra dos Órgãos, Southeastern Brazil

A new species of coccidia (Protozoa: Apicomplexa: Eimeriidae) found parasitizing the white-eyed parakeet Psittacara leucophthalmus (Müller, 1776) in Brazil is described. Eimeria psittacarae n. sp. has oocysts that are ellipsoidal, 34.8 × 24.3 μm, with smooth, bilayered wall, ~1.7 μm thick. Micropyle present. Oocyst residuum absent, but one or two polar granules are present. Sporocysts are elongate ellipsoidal, 19.2 × 9.7 μm. Stieda body knob-like and sub-Stieda body rounded. Sporocyst residuum is composed of granules that appear to be membrane-bounded. Sporozoites are vermiform with one refractile body and a nucleus. This is the sixth description of an eimeriid coccidium parasitizing a New World psittacine.

Transcriptomic and functional analysis of the oosome, a unique form of germ plasm in the waspNasonia vitripennis

BackgroundThe oosome is the germline determinant in the waspNasonia vitripennisand is homologous to the polar granules ofDrosophila. Despite a common evolutionary origin and developmental role, the oosome is morphologically quite distinct from polar granules. It is a solid sphere that migrates within the cytoplasm before budding out and forming pole cells.ResultsTo gain an understanding of both the molecular basis of the novel form of the oosome, and the conserved essential features of germ plasm, we quantified and compared transcript levels between embryo fragments that contained the oosome, and those that did not. The identity of the localized transcripts indicated thatNasoniauses different molecules to carry out conserved germ plasm functions. In addition, functional testing of a sample of localized transcripts revealed potentially novel mechanisms of ribonucleoprotein assembly and pole cell cellularization in the wasp.ConclusionsOur results demonstrate that numerous novel and unexpected molecules have been recruited in order produce the unique characteristics of the oosome and pole cell formation inNasonia. This work will serve as the basis for further investigation into the patterns of germline determinant evolution among insects, the molecular basis of extreme morphology of ribonucleoproteins, and the incorporation of novel components into developmental networks.

Isospora machadoae sp. nov. (Protozoa: Apicomplexa: Eimeriidae), a new coccidian species from white-necked thrushes Turdus albicolis (Passeriformes: Turdidae) of South America

A new coccidian species parasitizing white-necked thrushes Turdus albicollis Vieillot, 1818 is described from the Parque Nacional do Itatiaia, in Southeastern Brazil. Isospora machadoae sp. nov. has oocysts that are sub-spherical, 22.2 × 21.2 µm, with bilayered wall, ~1.3 μm thick. Outer layer is rough with micropyle and micropyle cap. Oocyst residuum is absent, but one or two polar granules are present. Sporocysts are ellipsoidal, 13.3 × 9.7 µm. The Stieda body is flattened to half-moon-shaped and substieda body rounded. Sporocyst residuum is present, composed of scattered spherules of different sizes. Sporozoites are vermiform with a refractile body and a nucleus. These parasitized thrushes had no apparent clinical signs of coccidiosis or high densities of oocysts in feces. This condition may be associated with a specific low pathogenicity of I. machadoae sp. nov. and/or with the conserved habitat of these birds, which ensures the ecological niches and thus the immunocompetence to wildlife.

Coccidial dispersion across trans- and cis-Andean antbirds (Passeriformes: Thamnophilidae): Isospora sagittulae (Apicomplexa: Eimeriidae) from nonsympatric hosts

Isospora sagittulae McQuistion and Capparella, 1992 (Protozoa: Apicomplexa: Eimeriidae) is reported from White-throated Antbirds (Gymnopithys salvini (Berlepsch, 1901)) and from Common Scale-backed Antbirds (Willisornis poecilinotus (Cabanis, 1847)), which are thamnophilid birds from the Brazilian Amazon. Its oocysts are ovoidal to ellipsoidal, 28.4 μm × 22.4 μm, with smooth, bilayered wall, 1.1 μm. Micropyle and oocyst residuum are absent, but one to three polar granules are present. Sporocysts are subspherical to ovoidal, 15.0 μm × 12.6 μm. Stieda body thin and flattened and substieda body triangular to round. Sporocyst residuum composed of scattered granules. Sporozoites with refractile body and nucleus. This coccidium was originally described from the Spotted Antbird (Hylophylax naevioides (Lafresnaye, 1847)), a trans-Andean antbird that is not sympatric with G. salvini and W. poecilinotus, which are cis-Andean antbirds from lowland Amazon forest; therefore, this current study presents some assumptions to explain the dispersion of I. sagittulae among antbird species.