Project title
Genomic analysis of Tasmanian Devil
Collaborators and funding
Contact(s)
- Ambikesh Jayal ambi.jayal@canberra.edu.au
Project description and aims
The project deals with the characterisation of the subtelomeres in the Tasmanian devil (TD) which is the largest carnivore marsupial in the Australian Dasyuridae family. TD is listed as a threatened species due to two facial tumours (devil facial tumour 1 (DFT1) and devil facial tumour 2 (DFT2)). These tumours have resulted in about 90% reduction in the TD population. The exact cause of these facial tumours is yet unknown (McCallum et al., 2007); however, the DFT1 is believed to have originated from telomeres (the end cap of linear chromosomes that protects it from degradation and end-to-end fusion) on one homologue of chromosomes 1 and X (Taylor et al., 2017).
Tasmanian devils are known for their unique telomeres including telomere length dimorphism, which means that the pair of homologous chromosomes have different telomere length (Bender et al., 2012). Another unique feature of the Tasmanian devil telomere is having non-canonical telomeres, where telomere sequences are interrupted by non-telomeric DNA arrays. These unique telomeres are not only specific to Tasmanian devils but also to other members of Australian marsupials (Ingles & Deakin, 2016).
The subtelomere is the adjacent region to the telomere sequences; this region serves as a transitional region between the telomere and the rest of the chromosome. One of its leading roles is maintaining the telomeric region, as well as regulating the transcription of the TERRA sequences (Telomeric Repeat-containing RNA), an essential component of the functional telomere (Kwapisz & Morillon, 2020). The rearrangements in the subtelomeres were found to be involved in a range of diseases and abnormalities, including mental retardation, recurrent miscarriages, infertility, haematological malignancies (Knight & Flint, 2000) and other cancers (Campion et al., 2021).
The subtelomeres of only a few species have been characterised so far; this includes humans, budding yeast and some human parasites (Plasmodium falciparum and Trypanosoma brucei) (Louis et al., 2014). However, this region has never been investigated in marsupials previously. Therefore, with its high-quality assembled genome, the Tasmanian devil ((mSarHar1.11) (GenBank assembly: GCA_902635505.1)) genome offers unique opportunity to investigate and characterise the terminal subtelomeric region in any marsupial. Also, given the unique structure of the Tasmanian devil telomere and its link to the facial tumour disease, the main threat to this species’ existence, there are other excellent reasons for investigating the Tasmanian devil subtelomeres.
The aims of this project
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Characterise the terminal and subtelomeric region of the Tasmanian devil chromosomes; this includes the characterisation of repeat sequences (e.g., transposable elements, simple repeats, telomeres and telomere-like sequences), genes, and segmental duplications.
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Compare the conservation status of this genomic region with other species like humans and finally.
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Explore the subtelomere’s role in regulating the Tasmanian devil’s unique telomere and its facial tumours.
How is ABLeS supporting this work?
This work is supported through the production bioinformatics scheme provided by ABLeS. The supports includes 1 TB temporary storage on scratch, 0.5 TB permenant storage and 50 KSUs per quarter.
Expected outputs enabled by participation in ABLeS
These details have been provided by project members at project initiation. For more information on the project, please consult the contact(s) or project links above.