| Title: |
Metabolic and transcriptional elucidation of the carotenoid biosynthesis pathway in peel and flesh tissue of loquat fruit during on-tree development |
| Authors: |
Margarita Hadjipieri, Egli C. Georgiadou, Alicia Marin, Huertas M. Diaz-Mula, Vlasios Goulas, Vasileios Fotopoulos, Francisco A. Tomás-Barberán, George A. Manganaris |
| Source: |
BMC Plant Biology, Vol 17, Iss 1, Pp 1-12 (2017) |
| Publisher Information: |
BMC, 2017. |
| Publication Year: |
2017 |
| Collection: |
LCC:Botany |
| Subject Terms: |
Eriobotrya japonica, Developmental stages, Maturation, Ripening, β-carotene, β-cryptoxanthin, Botany, QK1-989 |
| More Details: |
Abstract Background Carotenoids are the main colouring substances found in orange-fleshed loquat fruits. The aim of this study was to unravel the carotenoid biosynthetic pathway of loquat fruit (cv. ‘Obusa’) in peel and flesh tissue during distinct on-tree developmental stages through a targeted analytical and molecular approach. Results Substantial changes regarding colour parameters, both between peel and flesh and among the different developmental stages, were monitored, concomitant with a significant increment in carotenoid content. Key genes and individual compounds that are implicated in the carotenoid biosynthetic pathway were further dissected with the employment of molecular (RT-qPCR) and advanced analytical techniques (LC-MS). Results revealed significant differences in carotenoid composition between peel and flesh. Thirty-two carotenoids were found in the peel, while only eighteen carotenoids were identified in the flesh. Trans-lutein and trans-β-carotene were the major carotenoids in the peel; the content of the former decreased with the progress of ripening, while the latter registered a 7.2-fold increase. However, carotenoid profiling of loquat flesh indicated trans-β-cryptoxanthin, followed by trans-β-carotene and 5,8-epoxy-β-carotene to be the most predominant carotenoids. High amounts of trans-β-carotene in both tissues were supported by significant induction in a chromoplast-specific lycopene β-cyclase (CYCB) transcript levels. PSY1, ZDS, CYCB and BCH were up-regulated and CRTISO, LCYE, ECH and VDE were down-regulated in most of the developmental stages compared with the immature stage in both peel and flesh tissue. Overall, differential regulation of expression levels with the progress of on-tree fruit development was more evident in the middle and downstream genes of carotenoid biosynthetic pathway. Conclusions Carotenoid composition is greatly affected during on-tree loquat development with striking differences between peel and flesh tissue. A link between gene up- or down-regulation during the developmental stages of the loquat fruit, and how their expression affects carotenoid content per tissue (peel or flesh) was established. |
| Document Type: |
article |
| File Description: |
electronic resource |
| Language: |
English |
| ISSN: |
1471-2229 |
| Relation: |
http://link.springer.com/article/10.1186/s12870-017-1041-3; https://doaj.org/toc/1471-2229 |
| DOI: |
10.1186/s12870-017-1041-3 |
| Access URL: |
https://doaj.org/article/1dc387d100fe48afb7dedc83629c79d2 |
| Accession Number: |
edsdoj.1dc387d100fe48afb7dedc83629c79d2 |
| Database: |
Directory of Open Access Journals |
