Glutathione biosynthesis in Arabidopsis trichome cells
In <em>Arabidopsis thaliana</em>, trichome cells are specialized unicellular structures with uncertain functions. Based on earlier observations that one of the genes involved in cysteine biosynthesis (Atcys-3A) is highly expressed in trichomes, we have extended our studies in trichome ce...
| Main Authors: | , , , , , |
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| Format: | Journal article |
| Language: | English |
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National Academy of Sciences
2000
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| _version_ | 1797100805170397184 |
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| author | Gutiérrez-Alcalá, G Gotor, C Meyer, A Fricker, M Vega, J Romero, L |
| author_facet | Gutiérrez-Alcalá, G Gotor, C Meyer, A Fricker, M Vega, J Romero, L |
| author_sort | Gutiérrez-Alcalá, G |
| collection | OXFORD |
| description | In <em>Arabidopsis thaliana</em>, trichome cells are specialized unicellular structures with uncertain functions. Based on earlier observations that one of the genes involved in cysteine biosynthesis (Atcys-3A) is highly expressed in trichomes, we have extended our studies in trichome cells to determine their capacity for glutathione (GSH) biosynthesis. First, we have analyzed by <em>in situ</em> hybridization the tissue-specific expression of the genes Atcys-3A and sat5, which encode O-acetylserine(thio)lyase (OASTL) and serine acetyltransferase (SAT), respectively, as well as gsh1 and gsh2, which encode γ-glutamylcysteine synthetase and glutathione synthetase, respectively. The four genes are highly expressed in leaf trichomes of <em>Arabidopsis</em>, and their mRNA accumulate to high levels. Second, we have directly measured cytoplasmic GSH concentration in intact cells by laser-scanning microscopy after labeling with monochlorobimane as a GSH-specific probe. From these measurements, cytosolic GSH concentrations of 238 ± 25, 80 ± 2, and 144 ± 19 μM were estimated for trichome, basement, and epidermal cells, respectively. Taking into account the volume of the cells measured using stereological techniques, the trichomes have a total GSH content more than 300-fold higher than the basement and epidermal cells. Third, after NACl treatment, GSH biosynthesis is markedly decreased in trichomes. Atcys-3A, sat5, gsh1, and gsh2 mRNA levels show a decrease in transcript abundance, and [GSH] <sub>cyt</sub> is reduced to 47 ± 5 μM. These results suggest the important physiological significance of trichome cells related to GSH biosynthesis and their possible role as a sink during detoxification processes. |
| first_indexed | 2024-03-07T05:42:50Z |
| format | Journal article |
| id | oxford-uuid:e62bd552-00aa-4c9d-869c-3614d6448f2b |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T05:42:50Z |
| publishDate | 2000 |
| publisher | National Academy of Sciences |
| record_format | dspace |
| spelling | oxford-uuid:e62bd552-00aa-4c9d-869c-3614d6448f2b2022-03-27T10:29:25ZGlutathione biosynthesis in Arabidopsis trichome cellsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:e62bd552-00aa-4c9d-869c-3614d6448f2bPlant SciencesEnglishOxford University Research Archive - ValetNational Academy of Sciences2000Gutiérrez-Alcalá, GGotor, CMeyer, AFricker, MVega, JRomero, LIn <em>Arabidopsis thaliana</em>, trichome cells are specialized unicellular structures with uncertain functions. Based on earlier observations that one of the genes involved in cysteine biosynthesis (Atcys-3A) is highly expressed in trichomes, we have extended our studies in trichome cells to determine their capacity for glutathione (GSH) biosynthesis. First, we have analyzed by <em>in situ</em> hybridization the tissue-specific expression of the genes Atcys-3A and sat5, which encode O-acetylserine(thio)lyase (OASTL) and serine acetyltransferase (SAT), respectively, as well as gsh1 and gsh2, which encode γ-glutamylcysteine synthetase and glutathione synthetase, respectively. The four genes are highly expressed in leaf trichomes of <em>Arabidopsis</em>, and their mRNA accumulate to high levels. Second, we have directly measured cytoplasmic GSH concentration in intact cells by laser-scanning microscopy after labeling with monochlorobimane as a GSH-specific probe. From these measurements, cytosolic GSH concentrations of 238 ± 25, 80 ± 2, and 144 ± 19 μM were estimated for trichome, basement, and epidermal cells, respectively. Taking into account the volume of the cells measured using stereological techniques, the trichomes have a total GSH content more than 300-fold higher than the basement and epidermal cells. Third, after NACl treatment, GSH biosynthesis is markedly decreased in trichomes. Atcys-3A, sat5, gsh1, and gsh2 mRNA levels show a decrease in transcript abundance, and [GSH] <sub>cyt</sub> is reduced to 47 ± 5 μM. These results suggest the important physiological significance of trichome cells related to GSH biosynthesis and their possible role as a sink during detoxification processes. |
| spellingShingle | Plant Sciences Gutiérrez-Alcalá, G Gotor, C Meyer, A Fricker, M Vega, J Romero, L Glutathione biosynthesis in Arabidopsis trichome cells |
| title | Glutathione biosynthesis in Arabidopsis trichome cells |
| title_full | Glutathione biosynthesis in Arabidopsis trichome cells |
| title_fullStr | Glutathione biosynthesis in Arabidopsis trichome cells |
| title_full_unstemmed | Glutathione biosynthesis in Arabidopsis trichome cells |
| title_short | Glutathione biosynthesis in Arabidopsis trichome cells |
| title_sort | glutathione biosynthesis in arabidopsis trichome cells |
| topic | Plant Sciences |
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