日時：	2024年6月26日（水）15：00～16：30
場所：	Conference Room (134), 1st floor, Bldg. No.1 Institute for Life and Medical Sciences, Kyoto University （京都大学医生物学研究所　医生研１号館１階会議室(134室)） 本セミナーは、オンラインでも聴講可能です。 オンライン参加希望の方は、事前に連絡先(contact)までお知らせください。
演者：	Dr. Sakiko Shiga Department of Biological Sciences, Osaka University, Toyonaka, Japan
演題：	A two-day periodicity governed by the circadian clock system in a black chafer beetle Holotrichia parallela

講演要旨

Two-day rhythms, referred to as circa’bi’dian rhythms, have been reported in
humans and mosquitos. However, these rhythms only appear under constant
conditions, and the functional mechanisms of 2-day rhythms have been
unknown. We have recently reported clear circabidian rhythms of large black
chafers (Holotrichia parallela, Coleoptera) in the field and laboratory conditions.
Under 12 h:12 h light:dark cycles, H. parallela appeared on the ground in the
dark phase every 2 days. Under constant darkness, they exhibited free-running
rhythm with a period of 47.9±0.3 h. Phase responses of the circabidian rhythm
to light pulses suggested the circabidian rhythm is driven by the 24-h circadian
clock. A congeneric species Holotrichia picea also exhibited circabidian rhythm,
but day-switching of appearance and a circadian-like activity component were
sometimes observed. These also suggest the circadian clock system works
behind the circabidian rhythm. We are interested in biological significance and
mechanisms underlying the circabidian rhythm, and currently examine crucial
brain regions and roles of clock genes in the circabidian rhythm.
(Kawaski et al. 2017 J Exp Biol; Watanabe and Shiga 2020 J Comp Physiol A;
Shiga et al. 2022 Zool Sci)　(Language: English)

 

contact: Atsushi Mochizuki  Laboratory of Mathematical Biology,
Institute for Life and Medical Sciences, Kyoto University
Email: mochi＊infront.kyoto-u.ac.jp（＊→@に変更）
Tel: 075-751-4612