Telomeres, species differences, and unusual telomeres in vertebrates: presenting challenges and opportunities to understanding telomere dynamics

Emory D. Ingles; Janine E. Deakin; Emory D. Ingles; Janine E. Deakin

doi:10.3934/genet.2016.1.1

AIMS Genetics

2016, Volume 3, Issue 1: 1-24. doi: 10.3934/genet.2016.1.1

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Review

Telomeres, species differences, and unusual telomeres in vertebrates: presenting challenges and opportunities to understanding telomere dynamics

Emory D. Ingles ,
Janine E. Deakin ^,

Institute of Applied Ecology, University of Canberra, Canberra, ACT 2601, Australia

Received: 14 January 2016 Accepted: 03 March 2016 Published: 08 March 2016

There has been increasing interest in the use of telomeres as biomarkers of stress, cellular ageing and life-histories. However, the telomere landscape is a diverse feature, with noticeable differences between species, a fact which is highlighted by the unusual telomeres of various vertebrate organisms. We broadly review differences in telomere dynamics among vertebrates, and emphasize the need to understand more about telomere processes and trends across species. As part of these species differences, we review unusual telomeres in vertebrates. This includes mega-telomeres, which are present across a diverse set of organisms, but also focusing on the unusual telomeres traits of marsupials and monotremes, which have seen little to no prior discussion, yet uniquely stand out from other unusual telomere features discovered thus far. Due to the presence of at least two unique telomere features in the marsupial family Dasyuridae, as well as to the presence of physiological strategies semelparity and torpor, which have implications for telomere life-histories in these species, we suggest that this family has a very large potential to uncover novel information on telomere evolution and dynamics.
- telomere,
- mega-telomere,
- telomere length dimorphism,
- non-canonical telomere sequences,
- marsupial,
- dasyurid
Citation: Emory D. Ingles, Janine E. Deakin. Telomeres, species differences, and unusual telomeres in vertebrates: presenting challenges and opportunities to understanding telomere dynamics[J]. AIMS Genetics, 2016, 3(1): 1-24. doi: 10.3934/genet.2016.1.1

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Abstract

There has been increasing interest in the use of telomeres as biomarkers of stress, cellular ageing and life-histories. However, the telomere landscape is a diverse feature, with noticeable differences between species, a fact which is highlighted by the unusual telomeres of various vertebrate organisms. We broadly review differences in telomere dynamics among vertebrates, and emphasize the need to understand more about telomere processes and trends across species. As part of these species differences, we review unusual telomeres in vertebrates. This includes mega-telomeres, which are present across a diverse set of organisms, but also focusing on the unusual telomeres traits of marsupials and monotremes, which have seen little to no prior discussion, yet uniquely stand out from other unusual telomere features discovered thus far. Due to the presence of at least two unique telomere features in the marsupial family Dasyuridae, as well as to the presence of physiological strategies semelparity and torpor, which have implications for telomere life-histories in these species, we suggest that this family has a very large potential to uncover novel information on telomere evolution and dynamics.

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