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RNA interference reveals the escape response mechanism of Paramecium to mechanical stimulation. RNA干扰揭示草履虫对机械刺激的逃逸反应机制。

Biophysics and physicobiology Pub Date : 2023-05-31 eCollection Date: 2023-06-14 DOI: 10.2142/biophysico.bppb-v20.0025

Manabu Hori, Takashi Tominaga, Masaki Ishida, Mutsumi Kawano

{"title":"RNA interference reveals the escape response mechanism of Paramecium to mechanical stimulation.","authors":"Manabu Hori, Takashi Tominaga, Masaki Ishida, Mutsumi Kawano","doi":"10.2142/biophysico.bppb-v20.0025","DOIUrl":"10.2142/biophysico.bppb-v20.0025","url":null,"abstract":"In Paramecium, a mechanical stimulus applied to the posterior portion of the cell causes a transient increase in membrane permeability to potassium ions, transiently rendering the membrane in a hyperpolarized state. Hyperpolarization causes a transient increase in Cyclic adenosine monophosphate (cAMP) concentration in the cilia, resulting in a transient fast-forward swimming of the cell. Schultz and coworkers (1992) reported that a unique adenylate cyclase (AC)-coupled potassium channel is involved in the reaction underlying this response, which is known as the \"escape response.\" However, the AC responsible for this reaction remains to be identified. Moreover, the molecular linkage between mechanoreception and AC activation has not been elucidated adequately. Currently, we can perform an efficient and simple gene-knockdown technique in Paramecium using RNA interference (RNAi). Paramecium is one of the several model organisms for which whole-genome sequences have been elucidated. The RNAi technique can be applied to whole genome sequences derived from the Paramecium database (ParameciumDB) to investigate the types of proteins that elicit specific biological responses and compare them with those of other model organisms. In this review, we describe the applications of the RNAi technique in elucidating the molecular mechanism underlying the escape response and identifying the AC involved in this reaction. The findings of this study highlight the advantages of the RNAi technique and ParameciumDB.","PeriodicalId":101323,"journal":{"name":"Biophysics and physicobiology","volume":"20 2","pages":"e200025"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/ca/89/20_e200025.PMC10587447.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49695849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Flagellar polymorphism-dependent bacterial swimming motility in a structured environment. 结构环境中鞭毛多态性依赖的细菌游泳运动性。

Biophysics and physicobiology Pub Date : 2023-05-30 eCollection Date: 2023-06-14 DOI: 10.2142/biophysico.bppb-v20.0024

Yoshiaki Kinosita, Yoshiyuki Sowa

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引用次数: 0

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