Circannual rhythms often rely on endogenous seasonal photoperiodic timers involving 'clock' genes, and Clock gene polymorphism has been associated to variation in phenology in some bird species. In the long-distance migratory barn swallow Hirundo rustica, individuals bearing the rare Clock allele with the largest number of C-terminal polyglutamine repeats found in this species (Q8) show a delayed reproduction and moult later. We explored the association between Clock polymorphism and migration scheduling, as gauged by light-level geolocators, in two barn swallow populations (Switzerland; Po Plain, Italy). Genetic polymorphism was low: 91% of the 64 individuals tracked year-round were Q7/Q7 homozygotes. We compared the phenology of the rare genotypes with the phenotypic distribution of Q7/Q7 homozygotes within each population. In Switzerland, compared to Q7/Q7, two Q6/Q7 males departed earlier from the wintering grounds and arrived earlier to their colony in spring, while a single Q7/Q8 female was delayed for both phenophases. On the other hand, in the Po Plain, three Q6/Q7 individuals had a similar phenology compared to Q7/Q7. The Swiss data are suggestive for a role of genetic polymorphism at a candidate phenological gene in shaping migration traits, and support the idea that Clock polymorphism underlies phenological variation in birds.
Clock gene polymorphism and scheduling of migration : a geolocator study of the barn swallow Hirundo rustica / G. Bazzi, R. Ambrosini, M. Caprioli, A. Costanzo, F. Liechti, E. Gatti, L. Gianfranceschi, S. Podofillini, A. Romano, M. Romano, C. Scandolara, N. Saino, D. Rubolini. - In: SCIENTIFIC REPORTS. - ISSN 2045-2322. - 5(2015), pp. 12443.1-12443.7.
|Titolo:||Clock gene polymorphism and scheduling of migration : a geolocator study of the barn swallow Hirundo rustica|
BAZZI, GAIA (Primo)
SAINO, NICOLA MICHELE FRANCESCO (Penultimo)
RUBOLINI, DIEGO (Corresponding)
|Settore Scientifico Disciplinare:||Settore BIO/07 - Ecologia|
Settore BIO/18 - Genetica
|Data di pubblicazione:||2015|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1038/srep12443|
|Appare nelle tipologie:||01 - Articolo su periodico|