Hormone sensitive gene regulation in seasonal singing birds
Nature lovers are fascinated by the increasing number of singing birds when spring is approaching. Scientists also take advantage of this seasonal phenomenon because they are able to investigate the underlying mechanism, however the evolutionary and molecularbiological background is largely unknown.
A team of researchers from the Max Planck Institute for Ornithology in Seewiesen and from the Max Planck Institute for Molecular Genetics in Berlin have now identified the genome of the canary. With these data they were able to decipher the evolution of hormone-sensitive gene regulation in seasonal singing birds.
Canaries have been domesticated since the 15th century and are the descendants of the wild canary that lives on the Azores, Madeira and Canary Islands in the North Atlantic Ocean. Like their wild ancestors, domesticated canaries sing stereotyped songs under long-day (breeding) conditions and more variable songs under short-day (non-breeding) photoperiods.
The canary has become a preferred model to investigate the neurological changes affecting hormone-dependent song. This is because it has a pronounced reproductive season, with seasonal changes in song and steroid hormone concentrations, and a varying degree of brain plasticity between the breeding and the non-breeding season.
A team of researchers from the department of Behavioural Neurobiology around Manfred Gahr at the Max Planck Institute for Ornithology in Seewiesen and from the Sequencing Core Facility under guidance of Bernd Timmermann from the Max Planck Institute for Molecular Genetics in Berlin together with colleagues from Brazil and the UK now have studied how hormone-sensitive gene regulation has evolved in songbirds. The work resulted in the first high quality assembly and annotation of a female canary genome. In birds, females are the ‘heterogametic’ sex (ZW) and therefore the analysed genome sequence contained both types of sex chromosomes, says Heiner Kuhl from the Max Planck Institute for Molecular Genetics.
Whole genome alignments between the canary and already identified genomes throughout the bird taxa showed that on a global scale bird genomes are quite similar. However, differences appeared when comparisons were conducted on a finer scale. For example, at the level of the nucleotide there are considerable species differences, which can impact small genetic sequences, such as steroid hormone receptor binding sites. Such differences in these regions might lead to major differences in gene regulation, even between closely related species, says Carolina Frankl-Vilches from the Max Planck Institute for Ornithology.
Following this global analysis the scientists focused on gene networks that had three characteristics – were showing enrichment or under-representation in the expression profiles of the song control regions HVC and RA, showed seasonality, and were testosterone-sensitive. To verify whether the hormone-sensitive elements among these genes are specific for the canary, they also looked at the genes of the zebra finch because this species did not evolve hormone-sensitive song expression. Among all HVC expressed genes, including the seasonal and testosterone-induced gene pools, many were strictly canary-specific. These analyses reveal specific evolutionary changes in different parts of the song system that control seasonal singing behaviour.
Thus, in the canary, those genes that are sensitive for testosterone and estrogen, and are also involved in the rewiring of neurons, might be crucial for re-differentiation of the underlying neuronal substrate, such as HVC, leading to seasonal song patterning. The present study demonstrates the need for high-quality genome assembly to detect the evolution of genes in comparative studies, says the coordinator of the study, Manfred Gahr from the Max Planck Institute for Ornithology.
Carolina Frankl-Vilches, Heiner Kuhl, Martin Werber, Sven Klages, Martin Kerick, Antje Bakker, Edivaldo de Oliveira, Christina Reusch, Floriana Capuano, Jakob Vowinckel, Stefan Leitner, Markus Ralser, Bernd Timmermann, Manfred Gahr
Using the canary genome to decipher the evolution of hormone-sensitive gene regulation in seasonal singing birds
Genome Biology, 3 February 2015
Dr. Carolina Frankl-Vilches | Max Planck Institute for Ornithology, Seewiesen
Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz
Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences