Localization of circadian clock protein BMAL1 in the photoperiodic signal transduction machinery in Japanese quail

摘要: The circadian clock is a fundamental property of living organisms and involved in seasonal (photoperiodic) time measurement. Among vertebrates, birds have multiple pacemakers the eye, pineal gland, suprachiasmatic nucleus (SCN), highly sophisticated photoperiodic mechanisms. However, because removal these fails to abolish response, existence another "photoperiodic clock" has been suggested. Recent studies revealed that mediobasal hypothalamus (MBH) adjacent pars tuberalis (PT) pituitary gland constitute key components signal transduction machinery. In present study, we generated polyclonal antibody against chicken protein BMAL1 examine distribution Japanese quail brain by using immunohistochemistry. BMAL1-like immunoreactivity (lir) was confirmed medial SCN, which are critical pacemakers. We also observed strong MBH, including ependymal cells (ECs), infundibular (IN), median eminence (ME), PT. Furthermore, semiquantitative analysis suggested BMAL1-lir shows daily fluctuation regions. It possible clocks machinery such as PT EC may be regulation photoperiodism.