Hypothalamic deiodinase type-3 establishes the period of circannual interval timing in mammals

Dio3 expression is essential for establishing the period of circannual timing in Djungarian hamsters, but findings may not directly apply to humans.

Summary and findings

This study examined the role of deiodinase type-3 (Dio3) in circannual timing in Djungarian hamsters. The research involved transcriptomic sequencing and targeted mutation of Dio3 using CRISPR-Cas. Results indicated that Dio3 expression is crucial for establishing the period of circannual interval timing.

Abstract

Animals respond to environmental cues to time phenological events, but the intrinsic mechanism of circannual timing remains elusive. We used transcriptomic sequencing and frequent sampling of multiple hypothalamic nuclei in Djungarian hamster to examine the neural and molecular architecture of circannual interval timing. Our study identified three distinct phases of transcript changes, with deiodinase type-3 ( Dio3 ) expression activated during the early induction phase. Subsequent work demonstrated that targeted mutation of Dio3 using CRISPR-Cas resulted in a shorter period for circannual interval timing. Hamsters that are non-responsive to short photoperiod and fail to show any winter adaptations do not display changes in Dio3 expression do not show any change in body mass or pelage. Our work demonstrates that changes in Dio3 induction is essential for setting the period of circannual interval timing.

Elsewhere in the Pasireotide corpus