Fine-tuning of the flavonoid and monolignol pathways during apple early fruit development
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A coordinated regulation of different branches of the flavonoid pathway was highlighted that may contribute to elucidate the role of this important class of compounds during the early stages of apple fruit development.
Apple (Malus × domestica Borkh.) is an economically important fruit appreciated for its organoleptic characteristics and its benefits for human health. The first stages after fruit set represent a very important and still poorly characterized developmental process. To enable the profiling of genes involved in apple early fruit development, we combined the suppression subtractive hybridization (SSH) protocol to next-generation sequencing. We identified and characterized genes induced and repressed during fruit development in the apple cultivar ‘Golden Delicious’. Our results showed an opposite regulation of genes coding for enzymes belonging to flavonoid and monolignol pathways, with a strong induction of the former and a simultaneous repression of the latter. Two isoforms of phenylalanine ammonia-lyase and 4-coumarate:CoA ligase, key enzymes located at the branching point between flavonoid and monolignol pathways, showed opposite expression patterns during the period in analysis, suggesting a possible regulation mechanism. A targeted metabolomic analysis supported the SSH results and revealed an accumulation of the monomers catechin and epicatechin as well as several forms of procyanidin oligomers in apple fruitlets starting early after anthesis, together with a decreased production of other classes of flavonoids such as some flavonols and the dihydrochalcone phlorizin. Moreover, gene expression and metabolites accumulation of ‘Golden Delicious’ were compared to a wild apple genotype of Manchurian crabapple (Malus mandshurica (Maxim.) Kom.). Significant differences in both gene expression and metabolites accumulation were found between the two genotypes.
KeywordsApple Catechin Epicatechin Flavonoids Monolignols Next-generation sequencing SSH
We are grateful to Pierluigi Magnago for the maintenance of the orchard. This work was supported by the Autonomous Province of Trento “TranscrApple” grandi progetti 2012 to ASA.
- Benjamini Y, Hochberg Y (1995) Controlling the false discovery rate—a practical and powerful approach to multiple testing. J R Stat Soc Ser B Methodol 57:289–300Google Scholar
- Diatchenko L, Lau YF, Campbell AP, Chenchik A, Moqadam F, Huang B, Lukyanov S, Lukyanov K, Gurskaya N, Sverdlov ED, Siebert PD (1996) Suppression subtractive hybridization: a method for generating differentially regulated or tissue-specific cDNA probes and libraries. Proc Natl Acad Sci USA 93:6025–6030CrossRefPubMedPubMedCentralGoogle Scholar
- Gottardini E, Cristofori A, Pellegrini E, La Porta N, Nali C, Baldi P, Sablok G (2016) Suppression substractive hybridization and NGS reveal differential transcriptome expression profiles in wayfaring tree (Viburnum lantana L.) treated with ozone. Front Plant Sci 7:713CrossRefPubMedPubMedCentralGoogle Scholar
- Janssen BJ, Thodey K, Schaffer RJ, Alba R, Balakrishnan L, Bishop R, Bowen JH, Crowhurst RN, Gleave AP, Ledger S, McArtney S, Pichler FB, Snowden KC, Ward S (2008) Global gene expression analysis of apple fruit development from the floral bud to ripe fruit. BMC Plant Biol 8:16CrossRefPubMedPubMedCentralGoogle Scholar
- Lukyanov SA, Gurskaya NG, Lukyanov KA, Tarabykin VS, Sverdlov ED (1994) Highly efficient subtractive hybridization of cDNA. Bioorg Khim 20:701–704Google Scholar
- Onkokesung N, Reichelt M, van Doorn A, Schuurink RC, van Loon JJ, Dicke M (2014) Modulation of flavonoid metabolites in Arabidopsis thaliana through overexpression of the MYB75 transcription factor: role of kaempferol-3,7-dirhamnoside in resistance to the specialist insect herbivore Pieris brassicae. J Exp Bot 65:2203–2217CrossRefPubMedPubMedCentralGoogle Scholar
- Peer WA, Bandyopadhyay A, Blakeslee JJ, Makam SN, Chen RJ, Masson PH, Murphy AS (2004) Variation in expression and protein localization of the PIN family of auxin efflux facilitator proteins in flavonoid mutants with altered auxin transport in Arabidopsis thaliana. Plant Cell 16:1898–1911CrossRefPubMedPubMedCentralGoogle Scholar
- Pratt C (1988) Apple flower and fruit: morphology and anatomy. Horticultural reviews. Wiley, New York, pp 273–308Google Scholar
- Rohde A, Morreel K, Ralph J, Goeminne G, Hostyn V, De Rycke R, Kushnir S, Van Doorsselaere J, Joseleau JP, Vuylsteke M, Van Driessche G, Van Beeumen J, Messens E, Boerjan W (2004) Molecular phenotyping of the pal1 and pal2 mutants of Arabidopsis thaliana reveals far-reaching consequences on phenylpropanoid, amino Acid, and carbohydrate metabolism. Plant Cell 16:2749–2771CrossRefPubMedPubMedCentralGoogle Scholar