scholarly journals Endangered Australian marsupial species survive recent drought and megafires

Oryx ◽  
2021 ◽  
Vol 55 (6) ◽  
pp. 812-813
Author(s):  
Andrew M. Baker ◽  
Stephane Batista ◽  
Melinda J. Laidlaw ◽  
Lynn M. Baker ◽  
Ian C. Gynther ◽  
...  
Keyword(s):  
Marsupial Species ◽  
Australian Marsupial

scholarly journals In situ hybridization to detect bandicoot papillomatosis carcinomatosis virus type 1 in biopsies from endangered western barred bandicoots (Perameles bougainville)

2008 ◽  
Vol 89 (2) ◽  
pp. 419-423 ◽  
Author(s):  
Mark D. Bennett ◽  
Lucy Woolford ◽  
Amanda J. O'Hara ◽  
Kristin S. Warren ◽  
Philip K. Nicholls
Keyword(s):  
Virus Type ◽  
Host Interaction ◽  
Formalin Fixed Paraffin ◽  
Ffpe Samples ◽  
Formalin Fixed Paraffin Embedded ◽  
Marsupial Species ◽  
Australian Marsupial ◽  
Formalin Fixed

The western barred bandicoot (Perameles bougainville) is an endangered Australian marsupial species in which a papillomatosis and carcinomatosis syndrome occurs. Bandicoot papillomatosis carcinomatosis virus type 1 (BPCV1) is associated with the lesions of this progressively debilitating syndrome. Five digoxigenin-labelled DNA probes were generated for in situ hybridization (ISH) and the technique was optimized and performed on formalin-fixed paraffin-embedded (FFPE) biopsies. Staining of keratinocyte and sebocyte nuclei within lesions was achieved with all five probes. The sensitivity of ISH (76.9 %) surpassed that of PCR (30.8 %) for FFPE samples. The sensitivity of ISH varied from 81 % (papillomas) and 70 % (carcinoma in situ) to 29 % (squamous cell carcinomas). The specificity of the test was confirmed using an irrelevant probe and papillomas from other species. These results strengthen the association between BPCV1 and the western barred bandicoot papillomatosis and carcinomatosis syndrome and give insight into the biology of the virus–host interaction.

scholarly journals Ancient Viral Integrations in Marsupials: A Potential Antiviral Defence

2021 ◽  
Author(s):  
Emma F Harding ◽  
Alice G Russo ◽  
Grace J H Yan ◽  
Paul D Waters ◽  
Peter A White
Keyword(s):  
Viral Infections ◽  
Active Role ◽  
Tammar Wallaby ◽  
Eutherian Mammal ◽  
Brushtail Possum ◽  
Replicase Gene ◽  
Tasmanian Devil ◽  
Available N ◽  
Marsupial Species ◽  
Australian Marsupial

Abstract Marsupial viruses are understudied compared to their eutherian mammal counterparts, although they may pose severe threats to vulnerable marsupial populations. Genomic viral integrations, termed endogenous viral elements (EVEs) could protect the host from infection. It is widely known past viral infections and EVEs play an active role in antiviral defence in invertebrates and plants. This study aimed to characterise actively transcribed EVEs in Australian marsupial species, because they may play an integral role in cellular defence against viruses. This study screened publicly available RNA sequencing datasets (n=35) and characterised 200 viral transcripts from thirteen Australian marsupial species. Of the 200 transcripts, 188 originated from either Bornaviridae, Filoviridae or Parvoviridae EVEs. The other 12 transcripts were from putative active infections from members of the Herpesviridae and Anelloviridae, and Hepadnaviridae. EVE transcripts (n=188) were mapped to marsupial genomes (where available, n=5/13) to identify the genomic insertion sites. Of the 188 transcripts, 117 mapped to 39 EVEs within the koala, bare-nosed wombat, tammar wallaby, brushtail possum and Tasmanian devil genomes. The remaining eight animals had no available genome (transcripts n=71). Every marsupial have Bornaviridae, Filoviridae and Parvoviridae EVEs, a trend widely observed in eutherian mammals. Whilst eutherian bornavirus EVEs are predominantly nucleoprotein-derived, marsupial bornavirus EVEs demonstrate a surprising replicase gene bias. We predicted these widely distributed EVEs were conserved within marsupials from ancient germline integrations, as many were over 65 million years old. One bornavirus replicase EVE, present in six marsupial genomes, was estimated to be 160 million years old, predating the American-Australian marsupial split. We considered transcription of these EVEs through small non-coding RNA as an ancient viral defence. Consistent with this, in koala small RNA sequence datasets we detected Bornaviridae replicase and Filoviridae nucleoprotein produced piRNA. These were enriched in testis tissue, suggesting they could protect marsupials from vertically transmitted viral integrations.

Australian marsupial species identification

2011 ◽  
Vol 3 (1) ◽  
pp. e543-e544
Author(s):  
Linzi Wilson-Wilde ◽  
Janette Norman ◽  
James Robertson ◽  
Stephen Sarre ◽  
Arthur Georges
Keyword(s):  
Species Identification ◽  
Marsupial Species ◽  
Australian Marsupial

scholarly journals Viral fossils in marsupial genomes: secret cellular guardians

2021 ◽  
Vol 42 (3) ◽  
pp. 134
Author(s):  
Emma F Harding ◽  
Grace JH Yan ◽  
Peter A White
Keyword(s):  
Viral Evolution ◽  
Cellular Function ◽  
Defence Mechanism ◽  
Rna Molecules ◽  
Marsupial Species ◽  
Endogenous Viral Elements ◽  
Cellular Defence ◽  
Australian Marsupial

Genomic viral integrations, termed endogenous viral elements (EVEs), are fragments of viruses in host chromosomes that provide information about viral evolution and could even help protect the host from infection. In the present study we examined EVEs in thirteen different Australian marsupial species to identify trends in their integration, commonality and to investigate their possible cellular function. We found that marsupial EVEs are commonly derived from viruses of the Bornaviridae, Filoviridae and Parvoviridae families, and circulated up to 160 million years ago. We also show the EVEs are actively transcribed into both long and short RNA molecules in marsupials, and propose they are involved in a cellular defence mechanism to protect the germline from viral genomic invasion.

Mammary glands in male marsupials: I. Primordia in neonatal opossums Didelphis virginiana and Monodelphis domestica

Development ◽  
1990 ◽  
Vol 110 (2) ◽  
pp. 385-390
Author(s):  
M.B. Renfree ◽  
E.S. Robinson ◽  
R.V. Short ◽  
J.L. Vandeberg
Keyword(s):  
Sexual Differentiation ◽  
Mammary Glands ◽  
Monodelphis Domestica ◽  
Didelphis Virginiana ◽  
Marsupial Species ◽  
Australian Marsupial ◽  
Genital Tubercle

Neonates of the American didelphid marsupials Didelphis virginiana and Monodelphis domestica were sexed by karyotype and histologically examined on the day of birth. Mammary anlagen were found in both sexes of both species, but the neonatal males had less than one-third of the full female complement of mammary glands. Male neonates of both species also had paired scrotal bulges anterior to the genital tubercle but these were never present in females, once again raising the question of whether the pouch and scrotum are homologous structures. Mammary anlagen are not found in male neonates of the Australian marsupial species so far studied, which suggests a dichotomy in the control of some aspects of sexual differentiation in the two marsupial lineages.

MACROPODID MARSUPIAL LUTEINIZING HORMONE: VALIDATION OF ASSAY PROCEDURES AND CHANGES IN CONCENTRATIONS IN PLASMA DURING THE OESTROUS CYCLE IN THE FEMALE TAMMAR WALLABY (MACROPUS EUGENII)

1980 ◽  
Vol 86 (1) ◽  
pp. 1-12 ◽  
Author(s):  
R. L. SUTHERLAND ◽  
SUSAN M. EVANS ◽  
C. H. TYNDALE-BISCOE
Keyword(s):  
Limit Of Detection ◽  
Tammar Wallaby ◽  
Response Curves ◽  
Macropus Eugenii ◽  
Wide Range ◽  
Marsupial Species ◽  
Lh Rh ◽  
Lh Releasing Hormone ◽  
Australian Marsupial ◽  
Serial Dilutions

A heterologous double antibody radioimmunoassay employing a rabbit anti-ovine LH antiserum (GDN no. 15) has been developed for the assessment of concentrations of LH in macropodid marsupial pituitary extracts and plasma. In this radioimmunoassay system highly purified ovine, rat, human and kangaroo LH preparations demonstrated apparently parallel dose–response curves, as did serial dilutions of crude pituitary extracts from a wide range of Australian marsupial species and serial dilutions of plasma from ovariectomized, oestrous and LH releasing hormone (LH-RH)-treated marsupials. The assay has been used to monitor changes in immunoreactive LH in the plasma of the female tammar wallaby. Basal concentrations of LH in non-oestrous female wallabies were in the range < 0·20–1·90 ng/ml with many animals having values at or near the limit of detection of the assay. Concentrations of LH were markedly increased following ovariectomy (1·7–7·0 ng/ml), on the day of oestrus (10·0–> 50 ng/ml) and following administration of LH-RH (9·5–> 25·0 ng/ml). Plasma from hypophysectomized animals had no detectable LH immunoactivity, A well-defined LH surge, lasting approximately 12 h, was associated with oestrus. Mating occurred approximately 8 h before, and ovulation approximately 24 h after, the maximal concentration of LH in plasma.

Interspecific variation of zona pellucida glycoconjugates in several species of marsupial

Reproduction ◽  
2000 ◽  
pp. 111-120 ◽  
Author(s):  
JA Chapman ◽  
OW Wiebkin ◽  
WG Breed
Keyword(s):  
Glycine Max ◽  
Sialic Acid ◽  
Zona Pellucida ◽  
Fluorescein Isothiocyanate ◽  
Interspecific Variation ◽  
Lectin Histochemistry ◽  
Sialic Acids ◽  
Arachis Hypogea ◽  
Marsupial Species ◽  
Similar Intensity

The zona pellucida glycoconjugate content of several marsupial species was investigated using differential lectin histochemistry. Ovaries from fat-tailed dunnarts, a southern brown bandicoot, grey short-tailed opossums, brushtail possums, ringtail possums, koalas and eastern grey kangaroos were fixed, embedded in paraffin wax, sectioned and stained with ten fluorescein isothiocyanate-conjugated lectins. Sections were also incubated with either neuraminidase or saponified, respectively, before incubation with the lectins to identify saccharide residues masked by sialic acids or O-acetyl groups on sialic acids. The zonae pellucidae surrounding the oocytes of the marsupials demonstrated interspecific variation in glycoconjugate content, with mannose-containing glycoconjugates exhibiting the greatest variation. Some of the zona pellucida glycoconjugates of all species, except those of the opossums, were masked by sialic acid with an increase in fluorescence with lectins from Arachis hypogea (PNA), and Glycine max (SBA), after desialylation. The disaccharide beta-galactose(1-4)N-acetyl-D-glucosamine appeared to be conformationally masked by O-acetyl groups of sialic acids in the zonae pellucidae of all species, with an increase in fluorescence with the lectin from Erythrina cristagalli (ECA), after saponification. Similar intensity and localization of beta-(1-4)-N-acetyl-D-glucosamine, as shown by staining of the lectin from Triticum vulgaris (WGA), to the inner and outer regions of the zona pellucida, were found to those reported in eutherian species. WGA fluorescence became uniform throughout the zonae pellucidae after saponification, indicating differential O-acetylation of sialic acids on the internal compartment of the zonae pellucidae.

Population and Conservation Genetics of Marsupials

1989 ◽  
Vol 37 (3) ◽  
pp. 161 ◽  
Author(s):  
WB Sherwin ◽  
ND Murray
Keyword(s):  
Population Genetics ◽  
Conservation Genetics ◽  
Current Knowledge ◽  
Effective Size ◽  
Individual Species ◽  
Census Size ◽  
Electrophoretic Data ◽  
Marsupial Species ◽  
Small Effective Size ◽  
Census Number

This article summarises current knowledge of marsupial population genetics, and discusses its relevance to the conservation of marsupial species. It has been suggested that there is much lower genetic variation within marsupial populations than in eutherian mammals. This trend is not evident in the electrophoretic data summarised here. However, genetic differentiation between populations, subspecies, and species of marsupials appears to be slightly lower than comparable values for eutherians. Genetic estimates of migration between populations are scarce at present, but show values that are comparable with eutherians. Some studies of marsupial population genetics have used non-electrophoretic characteristics, or have addressed the possibility of selection on the characters analysed. Although few, these studies indicate the suitability of marsupials for such investigations. Recent debate over the theories and applications of conservation genetics has made it clear that more research is required on individual species. Given the record of extinction of marsupials in the last 200 years, it is important to test the applicability of these theories to individual marsupial species. Several examples are discussed emphasising the need for ecological studies that estimate the effective number of reproducing individuals per generation. This figure, called the effective size, is the corner- stone of conservation genetics theory, being an important determinant of both the rate of loss of variation between individuals, and the rate of inbreeding. The effective size of the mainland population of the eastern barred bandicoot, Perameles gunnii, appears to be only about one-tenth of its census number. This result is comparable with estimates made in other vertebrates, and demonstrates that many marsupial species which appear to have an adequate census size on ecological grounds may face genetic problems resulting from small effective size.

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