<i>CaFtsH06</i>, A Novel Filamentous Thermosensitive Protease Gene, Is Involved in Heat, Salt, and Drought Stress Tolerance of Pepper (<i>Capsicum annuum</i> L.)
Harsh environmental factors have continuous negative effects on plant growth and development, leading to metabolic disruption and reduced plant productivity and quality. However, filamentation temperature-sensitive H protease (FtsH) plays a prominent role in helping plants to cope with these negativ...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-06-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/22/13/6953 |
| Summary: | Harsh environmental factors have continuous negative effects on plant growth and development, leading to metabolic disruption and reduced plant productivity and quality. However, filamentation temperature-sensitive H protease (FtsH) plays a prominent role in helping plants to cope with these negative impacts. In the current study, we examined the transcriptional regulation of the <i>CaFtsH06</i> gene in the R9 thermo-tolerant pepper (<i>Capsicum annuum</i> L.) line. The results of qRT-PCR revealed that <i>CaFtsH06</i> expression was rapidly induced by abiotic stress treatments, including heat, salt, and drought. The CaFtsH06 protein was localized to the mitochondria and cell membrane. Additionally, silencing <i>CaFtsH06</i> increased the accumulation of malonaldehyde content, conductivity, hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) content, and the activity levels of superoxide dismutase and superoxide (·O<sub>2</sub><sup>−</sup>), while total chlorophyll content decreased under these abiotic stresses. Furthermore, <i>CaFtsH06</i> ectopic expression enhanced tolerance to heat, salt, and drought stresses, thus decreasing malondialdehyde, proline, H<sub>2</sub>O<sub>2</sub>, and ·O<sub>2</sub><sup>−</sup> contents while superoxide dismutase activity and total chlorophyll content were increased in transgenic Arabidopsis. Similarly, the expression levels of other defense-related genes were much higher in the transgenic ectopic expression lines than WT plants. These results suggest that <i>CaFtsH06</i> confers abiotic stress tolerance in peppers by interfering with the physiological indices through reducing the accumulation of reactive oxygen species, inducing the activities of stress-related enzymes and regulating the transcription of defense-related genes, among other mechanisms. The results of this study suggest that <i>CaFtsH06</i> plays a very crucial role in the defense mechanisms of pepper plants to unfavorable environmental conditions and its regulatory network with other <i>CaFtsH</i> genes should be examined across variable environments. |
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| ISSN: | 1661-6596 1422-0067 |