Changes in concentrations of circulating heat‐shock proteins in House Finches in response to different environmental stressors

Heat-shock proteins (HSP) are molecular chaperones that play key roles in the maintenance of cellular homeostasis under variable environmental conditions. Although HSP are frequently used in studies of wild vertebrates as indicators of stress, no one to date has assessed responses of HSP60, HSP70, and HSP90 in the same speciestodifferentenvironmentalstressors.WestudiedchangesinthecirculatingconcentrationsofHSP60,HSP70, and HSP90 in wild-caught House Finches (Haemorhous mexicanus) in response to multiple and sequential stressful environments, including high temperatures, transportation, and pathogen exposure. House Finches sampled during aperiodoflow-environmentalstresswithmoderateambienttemperatureshadlowlevelsofHSP60andmodestlevels ofHSP70andHSP90comparedtobirdssampledduringapresumablymorestressfulperiodwithhightemperatures. After exposure to high-ambient temperatures, transportation in a vehicle, and exposure to Mycoplasma gallisepticum, captive finches were found to have increasingly higher levels of HSP60. HSP70 tended to rise in response to each stressor, but to drop in the weeks between stress challenges. HSP90 levels increased significantly only in response to pathogen challenge. Our observations suggest that HSP60 and HSP70 are indices of a range of stressors in House Finches, whereas HSP90 primarily reflects health state. RESUMEN. Cambios en la concentraci´ on de proteproducidas por estrcausado por el calor (HSP), en Haemorhous mexicanus como respuesta a diferentes estresantes ambientales Prote´onas que se producen por el estrcausado por el calor (HSP) son chaperones moleculares que juegan un papel clave en el mantenimiento de la homeostasis celular bajo diferentes condiciones ambientales. Aunque las HSP sonutilizadasconfrecuenciaenestudiosdevertebradossilvestrescomoindicadoresdeestronadie ha tratado de determinar la respuesta de HSP60, HSP70 y HSP90, en la misma especie, bajo diferentes condiciones ambientales estresantes. Estudiamos los cambios en las concentraciones de HSP60, HSP70 y HSP90, en el sistema circulatorio de individuos de Haemorhous mexicanus silvestres capturados, como respuesta a m´ ultiples estresantes ambientales, incluyendo altas temperaturas, transportaciy exposici´