Photoperiodic regulation of type 2 deiodinase gene in djungarian hamster: Possible homologies between avian and mammalian photoperiodic regulation of reproduction

Miwa Watanabe, Shinobu Yasuo, Tsuyoshi Watanabe, Takashi Yamamura, Nobuhiro Nakao, Shizufumi Ebihara, Takashi Yoshimura

Research output: Contribution to journalArticlepeer-review

131 Citations (Scopus)

Abstract

The molecular mechanisms responsible for seasonal time measurement have yet to be fully described. Recently, we used differential analysis to identify that the type 2 iodothyronine deiodinase (Dio2) gene is responsible for the photoperiodic response of gonads in Japanese quail. It was found that expression of Dio2 in the mediobasal hypothalamus is induced by light and that T3 content in the mediobasal hypothalamus increased under long day conditions. In addition, we showed that intracerebroventricular infusion of T3 mimics photoperiodically induced testicular growth. Because it is well known that thyroid hormone is also essential for the maintenance of the seasonal reproductive changes in a number of mammals, we examined expression of Dio2 in Djungarian hamsters and found expression in the ependymal cell layer lining the infralateral walls of the third ventricle and the cell-clear zone overlying the tuberoinfundibular sulcus. Signal intensity was high under long days and weak under short days. Although light pulse did not affect Dio2 expression, melatonin injections decreased Dio2 expression under long days. These results indicate that Dio2 may be involved in the regulation of seasonal reproduction in mammals in the same way as observed in birds.

Original languageEnglish
Pages (from-to)1546-1549
Number of pages4
JournalEndocrinology
Volume145
Issue number4
DOIs
Publication statusPublished - Apr 2004
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Endocrinology

Fingerprint Dive into the research topics of 'Photoperiodic regulation of type 2 deiodinase gene in djungarian hamster: Possible homologies between avian and mammalian photoperiodic regulation of reproduction'. Together they form a unique fingerprint.

Cite this