TY - JOUR A1 - Frede, Katja A1 - Schreiner, Monika A1 - Baldermann, Susanne T1 - Light quality-induced changes of carotenoid composition in pak choi Brassica rapa ssp. chinensis N2 - Carotenoids as part of the photosystems are crucial for their assembly, light-harvesting, and photoprotection. Light of different wavelengths impacts the composition and structure of photosystems, thus offering the possibility to influence the carotenoid concentrations and composition in photosystems by illumination with specific narrow-banded light spectra. Key components involved in the regulation of gene transcription are still poorly characterized, particularly in leafy vegetables as compared to model plants. In particular, the effect of different light qualities and its connection to redox control mechanisms, which also determine the photosystem composition and structure, is not yet well understood. Furthermore, light quality effects are species-dependent, and thus, increase the need to perform research on individual vegetable species such as pak choi Brassica rapa ssp. chinensis. Here, we investigated the carotenoid concentrations and composition of pak choi sprouts grown for 6 days under blue, red, or white light emitting diodes (LEDs) as light source. After 6 days, the total carotenoid content was the highest under white and slightly reduced under blue or red LEDs. Blue, red, and white light differently affected the carotenoid composition mainly due to variations of the beta-carotene content which could be correlated to changes in the transcript levels of beta-carotene hydroxylase 1 (beta-OHASE1). Further investigations implied a redox controlled gene expression of beta-OHASE1. In addition, transcription factors related to light signaling and the circadian clock differed in their transcriptional abundance after exposure to blue and red light. RNA-Seq analysis also revealed increased transcript levels of genes encoding the outer antenna complex of photosystem II under red compared to blue light, indicating an adjustment of the photosystems to the different light qualities which possibly contributed to the alternations in the carotenoid content and composition. KW - Brassica rapa ssp. chinensis KW - beta-carotene hydroxylase KW - Carotenoids KW - LEDs KW - Light quality KW - Redox control Y1 - 2019 U6 - https://doi.org/10.1016/j.jphotobiol.2019.02.001 SN - 1011-1344 VL - 193 SP - 18 EP - 30 PB - Elsevier CY - Lausanne ER -