Metabolomic and transcriptomic analyses identify external conditions and key genes underlying high levels of toxic glycoalkaloids in tubers of stress-sensitive potato cultivars
(2023) In Frontiers in Plant Science 14.- Abstract
Introduction: High levels of toxic steroidal glycoalkaloids (SGAs) in potato tubers constitute a recognized food quality problem. Tuber SGA levels vary between potato cultivars and can increase after post-harvest stresses such as wounding and light exposure. A few cultivars, e.g., ‘Magnum Bonum’ and ‘Lenape,’ have been withdrawn from commercial sales due to excessive SGA levels during some cultivation years. However, these sudden SGA increases are diffucult to predict, and their causes are not understood. To identify external and genetic factors that underlie sudden SGA increases in certain potato cultivars, we have here in a 2-year study investigated ‘Magnum Bonum’ and five additional table potato cultivars for their SGA levels after... (More)
Introduction: High levels of toxic steroidal glycoalkaloids (SGAs) in potato tubers constitute a recognized food quality problem. Tuber SGA levels vary between potato cultivars and can increase after post-harvest stresses such as wounding and light exposure. A few cultivars, e.g., ‘Magnum Bonum’ and ‘Lenape,’ have been withdrawn from commercial sales due to excessive SGA levels during some cultivation years. However, these sudden SGA increases are diffucult to predict, and their causes are not understood. To identify external and genetic factors that underlie sudden SGA increases in certain potato cultivars, we have here in a 2-year study investigated ‘Magnum Bonum’ and five additional table potato cultivars for their SGA levels after wounding and light exposure. Results and methods: Results showed that ‘Magnum Bonum’ has an unusual strong SGA response to light exposure, but not to wounding, whereas ‘Bintje’ displayed an opposite regulation. Levels of calystegine alkaloids were not significantly altered by treatments, implicating independent metabolic regulation of SGA and calystegine levels also under conditions of high SGA accumulation. Metabolomic and transcriptomic analyses identified a small number of key genes whose expression correlated with SGA differences between cultivars. Overexpression of two key genes in transgenic low-SGA potato cultivars increased their leaf SGA levels significantly. Discussion: The results show that a strong response to light can underlie the SGA peaks that occasionally occur in certain potato cultivars and indicate that a between-cultivar variation in the expression of single SGA key genes can account for cultivar SGA differerences. We propose that current attempts to mitigate the SGA hazard will benefit from an increased consideration of cultivar-dependent SGA responses to post-harvest conditions, particularly light exposure. The identified key SGA genes can now be used as a molecular tool in this work.
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- author
- Merino, Irene ; Guasca, Alexandra Olarte ; Krmela, Ales ; Arif, Usman ; Ali, Ashfaq LU ; Westerberg, Erik ; Jalmi, Siddhi Kashinanth ; Hajslova, Jana ; Schulzova, Vera and Sitbon, Folke
- organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- abiotic stress, calystegines, glycoalkaloids, metabolomics, potato (Solanum tuberosum L.), solanine, transcriptomics
- in
- Frontiers in Plant Science
- volume
- 14
- article number
- 1210850
- publisher
- Frontiers Media S. A.
- external identifiers
-
- scopus:85174598783
- ISSN
- 1664-462X
- DOI
- 10.3389/fpls.2023.1210850
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: Copyright © 2023 Merino, Guasca, Krmela, Arif, Ali, Westerberg, Jalmi, Hajslova, Schulzova and Sitbon.
- id
- a3db15b2-c2d9-48d3-b673-900c040efbb2
- date added to LUP
- 2023-12-14 11:02:43
- date last changed
- 2023-12-18 14:38:12
@article{a3db15b2-c2d9-48d3-b673-900c040efbb2, abstract = {{<p>Introduction: High levels of toxic steroidal glycoalkaloids (SGAs) in potato tubers constitute a recognized food quality problem. Tuber SGA levels vary between potato cultivars and can increase after post-harvest stresses such as wounding and light exposure. A few cultivars, e.g., ‘Magnum Bonum’ and ‘Lenape,’ have been withdrawn from commercial sales due to excessive SGA levels during some cultivation years. However, these sudden SGA increases are diffucult to predict, and their causes are not understood. To identify external and genetic factors that underlie sudden SGA increases in certain potato cultivars, we have here in a 2-year study investigated ‘Magnum Bonum’ and five additional table potato cultivars for their SGA levels after wounding and light exposure. Results and methods: Results showed that ‘Magnum Bonum’ has an unusual strong SGA response to light exposure, but not to wounding, whereas ‘Bintje’ displayed an opposite regulation. Levels of calystegine alkaloids were not significantly altered by treatments, implicating independent metabolic regulation of SGA and calystegine levels also under conditions of high SGA accumulation. Metabolomic and transcriptomic analyses identified a small number of key genes whose expression correlated with SGA differences between cultivars. Overexpression of two key genes in transgenic low-SGA potato cultivars increased their leaf SGA levels significantly. Discussion: The results show that a strong response to light can underlie the SGA peaks that occasionally occur in certain potato cultivars and indicate that a between-cultivar variation in the expression of single SGA key genes can account for cultivar SGA differerences. We propose that current attempts to mitigate the SGA hazard will benefit from an increased consideration of cultivar-dependent SGA responses to post-harvest conditions, particularly light exposure. The identified key SGA genes can now be used as a molecular tool in this work.</p>}}, author = {{Merino, Irene and Guasca, Alexandra Olarte and Krmela, Ales and Arif, Usman and Ali, Ashfaq and Westerberg, Erik and Jalmi, Siddhi Kashinanth and Hajslova, Jana and Schulzova, Vera and Sitbon, Folke}}, issn = {{1664-462X}}, keywords = {{abiotic stress; calystegines; glycoalkaloids; metabolomics; potato (Solanum tuberosum L.); solanine; transcriptomics}}, language = {{eng}}, publisher = {{Frontiers Media S. A.}}, series = {{Frontiers in Plant Science}}, title = {{Metabolomic and transcriptomic analyses identify external conditions and key genes underlying high levels of toxic glycoalkaloids in tubers of stress-sensitive potato cultivars}}, url = {{http://dx.doi.org/10.3389/fpls.2023.1210850}}, doi = {{10.3389/fpls.2023.1210850}}, volume = {{14}}, year = {{2023}}, }