- 著者
- Jiro Osaka Haruka Yasuda Yusuke Watanuki Yuya Kato Yohei Nitta Atsushi Sugie Makoto Sato Takashi Suzuki
- 出版者
- The Genetics Society of Japan
- 雑誌
- Genes & Genetic Systems (ISSN:13417568)
- 巻号頁・発行日
- vol.97, no.6, pp.297-309, 2022-12-01 (Released:2023-04-18)
- 参考文献数
- 35
- 被引用文献数
- 3
Neural activity-dependent synaptic plasticity is an important physiological phenomenon underlying environmental adaptation, memory and learning. However, its molecular basis, especially in presynaptic neurons, is not well understood. Previous studies have shown that the number of presynaptic active zones in the Drosophila melanogaster photoreceptor R8 is reversibly changed in an activity-dependent manner. During reversible synaptic changes, both synaptic disassembly and assembly processes were observed. Although we have established a paradigm for screening molecules involved in synaptic stability and several genes have been identified, genes involved in stimulus-dependent synaptic assembly are still elusive. Therefore, the aim of this study was to identify genes regulating stimulus-dependent synaptic assembly in Drosophila using an automated synapse quantification system. To this end, we performed RNAi screening against 300 memory-defective, synapse-related or transmembrane molecules in photoreceptor R8 neurons. Candidate genes were narrowed down to 27 genes in the first screen using presynaptic protein aggregation as a sign of synaptic disassembly. In the second screen, we directly quantified the decreasing synapse number using a GFP-tagged presynaptic protein marker. We utilized custom-made image analysis software, which automatically locates synapses and counts their number along individual R8 axons, and identified cirl as a candidate gene responsible for synaptic assembly. Finally, we present a new model of stimulus-dependent synaptic assembly through the interaction of cirl and its possible ligand, ten-a. This study demonstrates the feasibility of using the automated synapse quantification system to explore activity-dependent synaptic plasticity in Drosophila R8 photoreceptors in order to identify molecules involved in stimulus-dependent synaptic assembly.
- 著者
- Karin Nakamura Shunsuke Tamba Atsushi Sugie Atsunori Mori
- 出版者
- (社)日本化学会
- 雑誌
- Chemistry Letters (ISSN:03667022)
- 巻号頁・発行日
- pp.130523, (Released:2013-06-29)
- 被引用文献数
- 9
Thiophene based block copolymers are synthesized by addition of bromothiophene and Knochel-Hauser base (TMPMgCl·LiCl). Nickel-catalyzed deprotonative C–H coupling polycondensation of 3-substituted-thiophenes proceeds to give head-to-tail-type poly(3-substituted thiophen-2,5-diyl) bearing nickel at the polymer end. Block copolymers of thiophene derivatives are obtained by successive addition of 2-bromo-3-alkylthiophene and magnesium amide to a living polythiophene end. The use of nickel catalyst bearing an o-tolyl group gives the tolyl-group-terminated thiophene diblock copolymers in highly efficiently. Triblock copolymer is also synthesized by the iterative addition of bromothiophene and TMPMgCl·LiCl.
- 著者
- Karin Nakamura Shunsuke Tamba Atsushi Sugie Atsunori Mori
- 出版者
- (社)日本化学会
- 雑誌
- Chemistry Letters (ISSN:03667022)
- 巻号頁・発行日
- vol.42, no.10, pp.1200-1202, 2013-10-05 (Released:2013-10-05)
- 参考文献数
- 38
- 被引用文献数
- 9
Thiophene-based block copolymers are synthesized by addition of bromothiophene and the Knochel–Hauser base (TMPMgCl·LiCl). Nickel-catalyzed deprotonative C–H coupling polycondensation of 3-substituted-thiophenes proceeds to give head-to-tail-type poly(3-substituted thiophen-2,5-diyl) bearing nickel at the polymer end. Block copolymers of thiophene derivatives are obtained by successive addition of 2-bromo-3-alkylthiophene and magnesium amide to a living polythiophene end. The use of nickel catalyst bearing an o-tolyl group gives the tolyl-group-terminated thiophene diblock copolymers in high efficiency. Triblock copolymer is also synthesized by the iterative addition of bromothiophene and TMPMgCl·LiCl.
- 著者
- Shunsuke Tamba Kanta Fuji Hikaru Meguro Shuji Okamoto Tadashi Tendo Ryo Komobuchi Atsushi Sugie Takashi Nishino Atsunori Mori
- 出版者
- (社)日本化学会
- 雑誌
- Chemistry Letters (ISSN:03667022)
- 巻号頁・発行日
- vol.42, no.3, pp.281-283, 2013-03-05 (Released:2013-02-23)
- 参考文献数
- 62
- 被引用文献数
- 36
High-molecular-weight head-to-tail-type regioregular polythiophenes are synthesized by [CpNiCl(SIPr)]-catalyzed dehydrobrominative polycondensation. Polycondensation of 2-bromo-3-hexylthiophene at the C–H bond proceeds with an equimolar amount of TMPMgCl·LiCl and a catalytic amount of [CpNiCl(SIPr)] to afford the regioregular poly(3-hexylthiophene) (HT-P3HT) with up to Mw = 815000. A self-standing HT-P3HT film is obtained with the regioregular HT-P3HT of Mw = 414000, while the attempted formation of the corresponding film with lower-molecular-weight HT-P3HT (Mw = 38000) is unsuccessful.