Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Telomere length as an indicator of life expectancy for the southern giant petrel

18.01.2011
The length of telomeres, the DNA fragments that protect the ends of chromosomes from deterioration, could be an indicator of life expectancy in the southern giant petrel (Macronectes giganteus), an emblematic species of the Antarctic and sub-Antarctic regions, according to an article published in the journal Behavioral Ecology by an international group of researchers including Dr. Jacob González-Solís, from the UB’s Department of Animal Biology and the Institute of Research of the Biodiversity (IRBio) at the University of Barcelona.

The project on which the article is based, which is directed by the expert Pat Monhagan (University of Glasgow, UK), also reveals that adult male giant petrels have shorter telomere lengths than females, a genetic difference that had not been documented until now in a scientific study of a bird species.

Telomeres, situated at the terminal end of chromosomes, are key elements in cell division. According to international research studies, telomeres shorten progressively with each cell division, and this reduction in length is associated with cell aging. The 2009 Nobel Prize for Medicine, awarded to Elizabeth H. Blackburn, Carol W. Greider and Jack Szostak, reflects the importance of the biological role of telomeres in cellular and molecular machinery.

The article in Behavioral Ecology focuses on a study of the giant petrel, a large scavenger found in the Arctic and sub-Antarctic regions which displays significant differences between males and females (size, behaviour, diet, etc), carried out in a breeding colony on Bird Island in South Georgia. “The giant petrel is a bird that can live over 50 years, making it ideal for studies of longevity”, says Dr. González-Solís, who nevertheless explains that, “It is not easy to study the effects of longevity in wild species. You need to be able to work with communities that have been extensively observed since the mid-part of the 20th century, which is the case of the colony on Bird Island, where we have been able to monitor petrels in different age groups”.

Why telomere length is different?

Male telomere length is known to be shorter in humans and in other animal species such as rats. The article in Behavioral Ecology looks at the genetic material of red blood cell samples taken from giant petrels and is the first research study to reveal differences in telomere length between males and females of the same bird species, raising the question of why telomere shortening is more pronounced in males than females. There appears to be no single explanation, although for González-Solís the different lifestyles of males and females may be one, if not the only, explanation: “There is a clear division of roles between males and females, particularly as regards feeding: males compete for the prey of seals and penguins on Antarctic beaches, whereas females feed on marine species including fish, squid or krill”. When animals have to compete for food, size is an advantage, and González-Solís explains that, “the specialized feeding strategies of males have led to an increase in body size, which raises the cell division rate and creates greater oxidative stress, hence the telomere shortening observed”. As he explains, “this is not consistent with observations in other dimorphic species such as the wandering albatross or the European shag, in which telomere length is similar between sexes”.

The difference in telomere length between males and females is also found in chicks, a finding that cannot be accounted for by lifestyle differences, since, as González-Solís explains, “At this stage the birds have not begun to display different behavioural patterns, so the different roles of males and females cannot be the only reason for the disparity in telomere lengths. In the case of chicks, perhaps it is simply that sexual dimorphism imposes different growth rates, which may promote greater telomere shortening in males. At the moment there are a number of theories and more research will be needed to work through them”.

Telomere length and bird survival

Another interesting finding of the study is the relationship between telomere length and bird survival, with those that died during the 8-year period after sampling having significantly shorter telomere lengths on average at the time of measurement. This suggests that telomere length may partially determine the life expectancy of giant petrels, independently of age and sex.

The southern giant petrel, a frequent victim of accidental capture by trawlers, is included on the Red List of Threatened Species maintained by the International Union for Conservation of Nature (IUCN). With an adult population that has fallen to 100,000, it is believed that thousands of these birds were killed inadvertently by illegal fishing vessels during the 1990s. In its future work, the team behind the study will focus on population genetics studies of colonies of giant petrels, a species with an extreme life-history strategy combining longevity and a low reproductive rate – females lay only one egg in each breeding season – that makes adults highly vulnerable to any type of survival threat.

Rosa Martínez | alfa
Further information:
http://www.ub.edu

More articles from Life Sciences:

nachricht Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>