Silencing of the phytoene desaturase (PDS) gene affects the expression of fruit-ripening genes in tomatoes

Abstract

Background Past research has shown that virus-induced phytoene desaturase (PDS) gene silencing via agroinjection in the attached and detached fruit of tomato plants results in a pale-yellow fruit phenotype. Although the PDS gene is often used as a marker for gene silencing in tomatoes, little is known about the role of PDS in fruit ripening. In this study, we investigated whether the pepper PDS gene silenced endogenous PDS genes in the fruit of two tomato cultivars, Dotaerang Plus and Legend Summer. Results We found that the pepper PDS gene successfully silenced endogenous PDS in tomato fruit at a silencing frequency of 100% for both cultivars. A pale-yellow silenced area was observed over virtually the entire surface of individual fruit due to the transcriptional reduction in phytoene desaturase (PDS), zeta-carotene (ZDS), prolycopene isomerase (CrtlSO), and beta-carotene hydroxylase (CrtR-b2), which are the carotenoid biosynthesis genes responsible for the red coloration in tomatoes. PDS silencing also affected the expression levels of the fruit-ripening genes Tomato AGAMOUS-LIKE1 (TAGL1), RIPENING INHIBITOR (RIN), pectin esterase gene (PE), lipoxygenase (LOX), FRUITFULL1/FRUITFUL2 (FUL1/FUL2), and the ethylene biosynthesis and response genes 1-aminocyclopropane-1-carboxylate oxidase 1 and 3 (ACO1 and ACO3) and ethylene-responsive genes (E4 and E8). Conclusion These results suggest that PDS is a positive regulator of ripening in tomato fruit, which must be considered when using it as a marker for virus-induced gene silencing (VIGS) experiments in order to avoid fruit-ripening side effects.

The bZIP transcription factor GmbZIP15 facilitates resistance against Sclerotinia sclerotiorum and Phytophthora sojae infection in soybean

“…To evaluate the efficacy of our VIGS system in soybean, we silenced the soybean phytoene desaturase ( GmPDS1 ), a gene involved in carotenoid biosynthesis ( Zhang et al., 2010 ), and obtained consistent photobleaching of the host plants ( Figure 3 A), which was used as an additional control to determine the success of gene silencing. TRV-PDS as an additional control in the VIGS system has been reported in many species, such as pepper ( Cai et al., 2015 ) and tomato ( Naing et al., 2019 ). After about 18–24 dpi, the TRV-GmPDS1-infected leaves began to become albino ( Figure 3 A) and the expression of the target genes ( GmbZIP15 and GmPDS1 ) were reduced to 20%–30% compared with the expression of these genes in empty vector control ( Figure 3 B).…”

Application of CRISPR/Cas9 genome editing system for molecular breeding of orchids

“…It is 1767bp from AUG to UAG in length, and total length of mRNA in database is 2176 bp (Figure 2A). The protein motive showed that there is Pf01593 amino oxidase protein family that might be im portant to function the phytoene desaturase enzyme in carotenoid biosynthesis pathway (Naing et al 2019). The DNA sequences of P. amabilis were selected as the can didates to determine the NGG as the protospacer adjacent motifs (PAM).…”

“…The PDS3 gene converts phytoene to colored ξcarotene in a twostep de saturation reaction (Wang et al 2009). PDS gene encoding the phytoene desaturase enzyme is involved in carotenoid biosynthesis pathway (Naing et al 2019), therefore muta tions in those genes cause albino phenotype (Koschmieder et al 2017). In general PDS3 gene is widely used as a com mon marker gene in many plant species due to its ease of detection.…”

An Efficient Virus-Induced Gene Silencing System for Functional Genomics Research in Walnut (Juglans regia L.) Fruits

“…Firstly, the feasibility of applying the VIGS-TRV system to silence genes in J. regia was verified by silencing the endogenous J. regia phytoene desaturase gene (JrPDS), an easily observable marker gene (Charrier et al, 2019;Naing et al, 2019). Then, a protocol for TRV virus infection on J. regia fruits was optimized using the PDS gene, after which the optimized protocol was applied to silence J. regia polyphenol oxidase genes (JrPPOs).…”