Characterizing the involvement of FaMADS9 in the regulation of strawberry fruit receptacle development

Abstract

FaMADS9 is the strawberry (Fragaria x ananassa) gene that exhibits the highest homology to the tomato (Solanum lycopersicum) RIN gene. Transgenic lines were obtained in which FaMADS9 was silenced. The fruits of these lines did not show differences in basic parameters, such as fruit firmness or colour, but exhibited lower Brix values in three of the four independent lines. The gene ontology MapMan category that was most enriched among the differentially expressed genes in the receptacles at the white stage corresponded to the regulation of transcription, including a high percentage of transcription factors and regulatory proteins associated with auxin action. In contrast, the most enriched categories at the red stage were transport, lipid metabolism and cell wall. Metabolomic analysis of the receptacles of the transformed fruits identified significant changes in the content of maltose, galactonic acid‐1,4‐lactone, proanthocyanidins and flavonols at the green/white stage, while isomaltose, anthocyanins and cuticular wax metabolism were the most affected at the red stage. Among the regulatory genes that were differentially expressed in the transgenic receptacles were several genes previously linked to flavonoid metabolism, such as MYB10, DIV, ZFN1, ZFN2, GT2, and GT5, or associated with the action of hormones, such as abscisic acid, SHP, ASR, GTE7 and SnRK2.7. The inference of a gene regulatory network, based on a dynamic Bayesian approach, among the genes differentially expressed in the transgenic receptacles at the white and red stages, identified the genes KAN1, DIV, ZFN2 and GTE7 as putative targets of FaMADS9. A MADS9‐specific CArG box was identified in the promoters of these genes.

Chromosome Level Assembly of Homozygous Inbred Line ‘Wongyo 3115’ Facilitates the Construction of a High-Density Linkage Map and Identification of QTLs Associated With Fruit Firmness in Octoploid Strawberry (Fragaria × ananassa)

“…In the present study, QTL regions, such as FIRM_5-1, FIRM_6-4, and FIRM_6-1b consisted of predicted regulatory genes. Recently, the importance of regulatory genes in the development of strawberry fruits and the possible molecular mechanism behind the firmness has been investigated (Vallarino et al, 2020). Several studies insisted the potential role of hormones and transcription factors in the development of fruit (Aharoni and O'Connell, 2002;Pillet et al, 2015;Hartl et al, 2017;Sánchez-Sevilla et al, 2017).…”

Transcriptome Analysis of the Fruit of Two Strawberry Cultivars “Sunnyberry” and “Kingsberry” That Show Different Susceptibility to Botrytis cinerea after Harvest

“…CER1 may play a crucial role in fruit wax formation [ 38 ]. Strawberries produce more alkane- than alcohol-type wax [ 39 ]. CER1 and LACS4 were relatively upregulated in “Kingsberry” after B. cinerea inoculation ( Figure 5 ).…”

Down-regulation of Fra a 1.02 in strawberry fruits causes transcriptomic and metabolic changes compatible with an altered defense response

“…cv. Camarosa, grown in a greenhouse under natural light and temperature ~24 °C, as previously reported 50 . The construct for the post-transcriptional silencing of Fra a 1.02 was generated from a 124-bp fragment of the gene FaFra a 1.02 (GenBank GQ148818) as shown in the Fig.…”