News News

Pheomelanin synthesis varies with protein food abundance in developing goshawks

The accumulation of the amino acid cysteine in lysosomes produces toxic substances, which are avoided by a gene (CTNS) coding for a transporter that pumps cystine out of lysosomes. Melanosomes are lysosome-related organelles that synthesize melanins, the most widespread pigments in animals. The synthesis of the orange melanin, termed pheomelanin, depends on cysteine levels because the sulfhydryl group is used to form the pigment. Pheomelanin synthesis may, therefore, be affected by cysteine homeostasis, although this has never been explored in a natural system. As diet is an important source of cysteine, here such an effect was indirectly tested by searching for an association between food abundance and pheomelanin content of feathers in a wild population of Northern goshawk Accipiter gentilis. As predicted on the basis that CTNS expression may inhibit pheomelanin synthesis and increase with food abundance -as previously found in other strictly carnivorous birds- the feather pheomelanin content in nestling goshawks, but not in adults, decreased as the abundance of prey available to them increased. In contrast, variation in the feather content of the non-sulphurated melanin form (eumelanin) was only explained by sex in both nestlings and adults. The feather pheomelanin content of nestlings was also found negatively related to that of their mothers, suggesting a relevant environmental influence on pheomelanin synthesis. Overall, these findings suggest that variation in pheomelanin synthesis may be a side effect of the maintenance of cysteine homeostasis. This may help explaining variability in the expression of pigmented phenotypes. informacion[at]ebd.csic.es: Galván et al (2019) Pheomelanin synthesis varies with protein food abundance in developing goshawks. J Comp Physiol B https://doi.org/10.1007/s00360-019-01222-y


https://link.springer.com/article/10.1007/s00360-019-01222-y
Average (0 Votes)

Latest News Latest News

Optimization of protocols for DNA extraction from fecal samples

High-throughput sequencing offers new possibilities in molecular ecology and conservation studies. However, its potential has not yet become fully exploited for noninvasive studies of...

Argentine ants harm nestlings of the blue tit

The consequences of ant invasions on ecosystems may only become apparent after long periods. In addition, predicting how sensitive native fauna will respond is only possible if the underlying...

Deep genetic divergences between the lowland Sunda tree squirrels

A surprising amount of hidden phylogenetic diversity exists in the small to medium size, drab colored squirrels of the genus Sundasciurus. This genus is endemic to Sundaland and the Philippines,...

Doñana’s Retuerta horse

The Retuerta horse is mainly located in the Doñana National Park, specifically in the Doñana Biological Reserve, and in the Guadiamar Reserve. It counts with an approximate population of 300...