Mediterranean Pine Vole, <i>Microtus duodecimcostatus:</i> A Paradigm of an Opportunistic Breeder
Miguel Lao-Pérez,
Diaa Massoud,
Francisca M. Real,
Alicia Hurtado,
Esperanza Ortega,
Miguel Burgos,
Rafael Jiménez,
Francisco J. Barrionuevo
Affiliations
Miguel Lao-Pérez
Departamento de Genética e Instituto de Biotecnología, Lab. 127, Centro de Investigación Biomédica, Universidad de Granada, Avenida del Conocimiento S/N, 18016 Armilla, Granada, Spain
Diaa Massoud
Departamento de Genética e Instituto de Biotecnología, Lab. 127, Centro de Investigación Biomédica, Universidad de Granada, Avenida del Conocimiento S/N, 18016 Armilla, Granada, Spain
Francisca M. Real
Departamento de Genética e Instituto de Biotecnología, Lab. 127, Centro de Investigación Biomédica, Universidad de Granada, Avenida del Conocimiento S/N, 18016 Armilla, Granada, Spain
Alicia Hurtado
Departamento de Genética e Instituto de Biotecnología, Lab. 127, Centro de Investigación Biomédica, Universidad de Granada, Avenida del Conocimiento S/N, 18016 Armilla, Granada, Spain
Esperanza Ortega
Departamento de Bioquímica y Biología Molecular III e Inmunología, Facultad de Medicina, Universidad de Granada, 18016 Armilla, Granada, Spain
Miguel Burgos
Departamento de Genética e Instituto de Biotecnología, Lab. 127, Centro de Investigación Biomédica, Universidad de Granada, Avenida del Conocimiento S/N, 18016 Armilla, Granada, Spain
Rafael Jiménez
Departamento de Genética e Instituto de Biotecnología, Lab. 127, Centro de Investigación Biomédica, Universidad de Granada, Avenida del Conocimiento S/N, 18016 Armilla, Granada, Spain
Francisco J. Barrionuevo
Departamento de Genética e Instituto de Biotecnología, Lab. 127, Centro de Investigación Biomédica, Universidad de Granada, Avenida del Conocimiento S/N, 18016 Armilla, Granada, Spain
Most mammalian species of the temperate zones of the Earth reproduce seasonally, existing a non-breeding period in which the gonads of both sexes undergo functional regression. It is widely accepted that photoperiod is the principal environmental cue controlling these seasonal changes, although several exceptions have been described in other mammalian species in which breeding depends on cues such as food or water availability. We studied the circannual reproductive cycle in males of the Mediterranean pine vole, Microtus duodecimcostatus, in the Southeastern Iberian Peninsula. Morphological, hormonal, functional, molecular and transcriptomic analyses were performed. As reported for populations of other species from the same geographic area, male voles captured in wastelands underwent seasonal testis regression in summer whereas, surprisingly, those living either in close poplar plantations or in our animal house reproduced throughout the year, showing that it is the microenvironment of a particular vole subpopulation what determines its reproductive status and that these animals are pure opportunistic, photoperiod-independent breeders. In addition, we show that several molecular pathways, including MAPK, are deregulated and that the testicular “immune privilege” is lost in the inactive testes, providing novel mechanisms linking seasonal testosterone reduction and testis regression.