Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in <i>Arabidopsis</i>
Target of rapamycin (TOR) acts as a master regulator in coordination of cell growth with energy and nutrient availability. Despite the increased appreciation of the essential role of the TOR complex in interaction with phytohormone signaling, little is known about its function on ethylene signaling....
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MDPI AG
2020-04-01
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| Series: | International Journal of Molecular Sciences |
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| Online Access: | https://www.mdpi.com/1422-0067/21/8/2680 |
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| author | Fengping Zhuo Fangjie Xiong Kexuan Deng Zhengguo Li Maozhi Ren |
| author_facet | Fengping Zhuo Fangjie Xiong Kexuan Deng Zhengguo Li Maozhi Ren |
| author_sort | Fengping Zhuo |
| collection | DOAJ |
| description | Target of rapamycin (TOR) acts as a master regulator in coordination of cell growth with energy and nutrient availability. Despite the increased appreciation of the essential role of the TOR complex in interaction with phytohormone signaling, little is known about its function on ethylene signaling. Here, through expression analysis, genetic and biochemical approaches, we reveal that TOR functions in the regulation of ethylene signals. Transcriptional analysis indicates that TOR inhibition by AZD8055 upregulated senescence- and ethylene-related genes expression. Furthermore, ethylene insensitive mutants like <i>etr1-1</i>, <i>ein2-5</i> and <i>ein3 eil1</i>, showed more hyposensitivity to AZD8055 than that of WT in hypocotyl growth inhibition. Similarly, blocking ethylene signals by ethylene action inhibitor Ag+ or biosynthesis inhibitor aminoethoxyvinylglycine (AVG) largely rescued hypocotyl growth even in presence of AZD8055. In addition, we also demonstrated that Type 2A phosphatase-associated protein of 46 kDa (TAP46), a downstream component of TOR signaling, physically interacts with 1-aminocy-clopropane-1-carboxylate (ACC) synthase ACS2 and ACS6. <i>Arabidopsis</i> overexpressing ACS2 or ACS6 showed more hypersensitivity to AZD8055 than WT in hypocotyl growth inhibition. Moreover, ACS2/ACS6 protein was accumulated under TOR suppression, implying TOR modulates ACC synthase protein levels. Taken together, our results indicate that TOR participates in negatively modulating ethylene signals and the molecular mechanism is likely involved in the regulation of ethylene biosynthesis by affecting ACSs in transcription and protein levels. |
| first_indexed | 2024-03-10T20:31:28Z |
| format | Article |
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| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-10T20:31:28Z |
| publishDate | 2020-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-e54f5658d2744066bcc908e28514e1642023-11-19T21:24:06ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672020-04-01218268010.3390/ijms21082680Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in <i>Arabidopsis</i>Fengping Zhuo0Fangjie Xiong1Kexuan Deng2Zhengguo Li3Maozhi Ren4School of Life Sciences, Chongqing University, Chongqing 401331, ChinaSchool of Life Sciences, Chongqing University, Chongqing 401331, ChinaSchool of Life Sciences, Chongqing University, Chongqing 401331, ChinaSchool of Life Sciences, Chongqing University, Chongqing 401331, ChinaSchool of Life Sciences, Chongqing University, Chongqing 401331, ChinaTarget of rapamycin (TOR) acts as a master regulator in coordination of cell growth with energy and nutrient availability. Despite the increased appreciation of the essential role of the TOR complex in interaction with phytohormone signaling, little is known about its function on ethylene signaling. Here, through expression analysis, genetic and biochemical approaches, we reveal that TOR functions in the regulation of ethylene signals. Transcriptional analysis indicates that TOR inhibition by AZD8055 upregulated senescence- and ethylene-related genes expression. Furthermore, ethylene insensitive mutants like <i>etr1-1</i>, <i>ein2-5</i> and <i>ein3 eil1</i>, showed more hyposensitivity to AZD8055 than that of WT in hypocotyl growth inhibition. Similarly, blocking ethylene signals by ethylene action inhibitor Ag+ or biosynthesis inhibitor aminoethoxyvinylglycine (AVG) largely rescued hypocotyl growth even in presence of AZD8055. In addition, we also demonstrated that Type 2A phosphatase-associated protein of 46 kDa (TAP46), a downstream component of TOR signaling, physically interacts with 1-aminocy-clopropane-1-carboxylate (ACC) synthase ACS2 and ACS6. <i>Arabidopsis</i> overexpressing ACS2 or ACS6 showed more hypersensitivity to AZD8055 than WT in hypocotyl growth inhibition. Moreover, ACS2/ACS6 protein was accumulated under TOR suppression, implying TOR modulates ACC synthase protein levels. Taken together, our results indicate that TOR participates in negatively modulating ethylene signals and the molecular mechanism is likely involved in the regulation of ethylene biosynthesis by affecting ACSs in transcription and protein levels.https://www.mdpi.com/1422-0067/21/8/2680target of rapamycingene expressionhypocotyl growth inhibitionTAP46-ACS2/6 interactionethylene signals<i>Arabidopsis</i> |
| spellingShingle | Fengping Zhuo Fangjie Xiong Kexuan Deng Zhengguo Li Maozhi Ren Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in <i>Arabidopsis</i> International Journal of Molecular Sciences target of rapamycin gene expression hypocotyl growth inhibition TAP46-ACS2/6 interaction ethylene signals <i>Arabidopsis</i> |
| title | Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in <i>Arabidopsis</i> |
| title_full | Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in <i>Arabidopsis</i> |
| title_fullStr | Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in <i>Arabidopsis</i> |
| title_full_unstemmed | Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in <i>Arabidopsis</i> |
| title_short | Target of Rapamycin (TOR) Negatively Regulates Ethylene Signals in <i>Arabidopsis</i> |
| title_sort | target of rapamycin tor negatively regulates ethylene signals in i arabidopsis i |
| topic | target of rapamycin gene expression hypocotyl growth inhibition TAP46-ACS2/6 interaction ethylene signals <i>Arabidopsis</i> |
| url | https://www.mdpi.com/1422-0067/21/8/2680 |
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