Identification of a GLDH-overexpressing Arabidopsis mutant and its responses to high-light stress
Ascorbic acid (AsA) is an important antioxidant protecting plant against environmental stresses. L-galactono-1,4-lactone dehydrogenase (GLDH) is a key enzyme in AsA synthesis pathway. To investigate the roles of AsA in mitigating high light (HL) damage, Arabidopsis GLDH mutants SALK_060087 and SALK_...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Academy of Sciences of the Czech Republic, Institute of Experimental Botany
2019-01-01
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| Series: | Photosynthetica |
| Subjects: | |
| Online Access: | https://ps.ueb.cas.cz/artkey/phs-201901-0037_identification-of-a-gldh-overexpressing-arabidopsis-mutant-and-its-responses-to-high-light-stress.php |
| Summary: | Ascorbic acid (AsA) is an important antioxidant protecting plant against environmental stresses. L-galactono-1,4-lactone dehydrogenase (GLDH) is a key enzyme in AsA synthesis pathway. To investigate the roles of AsA in mitigating high light (HL) damage, Arabidopsis GLDH mutants SALK_060087 and SALK_008236 with altered GLDH-expression were screened for homozygotes. No homozygotes were identified from SALK_060087, but most individuals of the SALK_008236 line (GLDH-236OE) were GLDH-overexpressing homozygous mutants accumulating more AsA than wild type (WT). An investigation of the physiological responses to HL demonstrated that the chlorophyll fluorescence parameters were significantly higher in GLDH-236OE than that in WT after 14-d HL. The degradation of photosynthetic pigment in WT was more severe than that in GLDH-236OE. GLDH-236OE accumulated more AsA, anthocyanins, flavonoids, and phenolics, while WT accumulated more reactive oxygen species (ROS) during HL. Our results suggest that GLDH-236OE have lesser sensitivity and higher tolerance to HL due to a higher capacity to eliminate ROS, absorb extra light, and dissipate thermal energy. |
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| ISSN: | 0300-3604 1573-9058 |