Université de Fribourg

Adaptation to developmental diet influences the response to selection on age at reproduction in the fruit fly

May, Christina M. ; Heuvel, Joost van den ; Doroszuk, Agnieszka ; Hoedjes, Katja M. ; Flatt, Thomas ; Zwaan, Bas J.

In: Journal of Evolutionary Biology, 2019, vol. 32, no. 5, p. 425–437

Experimental evolution (EE) is a powerful tool for addressing how environmental factors influence life‐history evolution. While in nature different selection pressures experienced across the lifespan shape life histories, EE studies typically apply selection pressures one at a time. Here, we assess the consequences of adaptation to three different developmental diets in combination with...

Université de Fribourg

The adaptive significance of chromosomal inversion polymorphisms in Drosophila melanogaster

Kapun, Martin ; Flatt, Thomas

In: Molecular Ecology, 2019, vol. 28, no. 6, p. 1263–1282

Chromosomal inversions, structural mutations that reverse a segment of a chromosome, cause suppression of recombination in the heterozygous state. Several studies have shown that inversion polymorphisms can form clines or fluctuate predictably in frequency over seasonal time spans. These observations prompted the hypothesis that chromosomal rearrangements might be subject to spatially and/or ...

Université de Fribourg

The genomic and physiological basis of life history variation in a butterfly metapopulation

Klepsatel, Peter ; Flatt, Thomas

In: Molecular Ecology, 2011, vol. 20, no. 9, p. 1795-1798

Unravelling the mechanisms underlying variation in life history traits is of fundamental importance for our understanding of adaptation by natural selection. While progress has been made in mapping fitness-related phenotypes to genotypes, mainly in a handful of model organisms, functional genomic studies of life history adaptations are still in their infancy. In particular, despite a few notable...

Université de Fribourg

The Evolution of Aging

Fabian, Daniel ; Flatt, Thomas

In: Nature Education Knowledge, 2011, vol. 3, no. 3, p. 1-10

Université de Fribourg

RTerseaanrchs acrtricileptome analysis reveals a major impact of JAK protein tyrosine kinase 2 (Tyk2) on the expression of interferon-responsive and metabolic genes

Vogl, Claus ; Flatt, Thomas ; Fuhrmann, Bernd ; Hofmann, Elisabeth ; Wallner, Barbara ; Stiefvater, Rita ; Kovarik, Pavel ; Strobl, Birgit ; Müller, Mathias

In: BMC Genomics, 2010, vol. 11, no. 199, p. 1-19

Background: Tyrosine kinase 2 (Tyk2), a central component of Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling, has major effects on innate immunity and inflammation. Mice lacking Tyk2 are resistant to endotoxin shock induced by lipopolysaccharide (LPS), and Tyk2 deficient macrophages fail to efficiently induce interferon alpha/beta after LPS treatment. However,...

Université de Fribourg

Host range and Specificity of the Drosophila C Virus

Kapun, Martin ; Nolte, Viola ; Flatt, Thomas ; Schlötterer, Christian

In: PLoS ONE, 2010, vol. 5, no. 8, p. 1-5

Background: The Drosophila C virus (DCV) is a common and well-studied Drosophila pathogen. Although natural infections are known from Drosophila melanogaster and D. simulans, and artificial infections have been reported from several. Drosophila species and other insects, it remains unclear to date whether DCV infections also occur naturally in other Drosophila species. Methods/Principal Findings:...

Université de Fribourg

Aging and Its Demographic Measurement

Bronikowski, Anne M. ; Flatt, Thomas

In: Nature Education Knowledge, 2010, vol. 1, no. 12, p. 1-6

This case study highlights the general issues raised earlier. First, that maximum lifespan is not an easily obtainable metric. Specifically, it is unambiguous in the sense that once the last animal dies, it is most definitely dead. But to estimate the variance in maximum lifespan, many replicate populations would need to be followed for each treatment group (with each replicate providing a single...

Université de Fribourg

Diet and longevity in the balance

Flatt, Thomas

In: Nature, 2009, vol. 462, no. 24, p. 989-990

Dietary restriction promotes longevity but impairs fecundity in many organisms. When the amino acids in a diet are fine-tuned, however, lifespan can be increased without loss of fecundity — at least in fruitflies.

Université de Fribourg

dSir2 and Dmp53 interact to mediate aspects of CR‐dependent life span extension in D. melanogaster

Bauer, Johannes H. ; Morris, Siti Nur Sarah ; Chang, Chenguyi ; Flatt, Thomas ; Wood, Jason G. ; Helfand, Stephen L.

In: Aging, 2009, vol. 1, no. 1, p. 38-48

Calorie Restriction (CR) is a well established method of extending life span in a variety of organisms. In the fruit fly D. melanogaster, CR is mediated at least in part by activation of dSir2. In mammalian systems, one of the critical targets of Sir2 is the tumor suppressor p53. This deacetylation of p53 by Sir2 leads to inhibition of p53's transcriptional activity. We have recently shown that...

Université de Fribourg

Hormonal regulation of the humoral innate immune response in Drosophila melanogaster

Flatt, Thomas ; Heyland, Andreas ; Rus, Florentina ; Porpiglia, Ermelinda ; Sherlock, Chris ; Yamamoto, Rochele ; Garbuzov, Alina ; Palli, Subba R. ; Tatar, Marc ; Silverman, Neal

In: The Journal of Experimental Biology, 2008, vol. 21, no. 1, p. 2712-2724

Juvenile hormone (JH) and 20-hydroxy-ecdysone (20E) are highly versatile hormones, coordinating development, growth, reproduction and aging in insects. Pulses of 20E provide key signals for initiating developmental and physiological transitions, while JH promotes or inhibits these signals in a stage-specific manner. Previous evidence suggests that JH and 20E might modulate innate immunity, but...