Preprint Article Version 1 This version is not peer-reviewed

RNAi-Mediated Down-Regulation of Dicer-Like 2 and 4 Changes the Response of “Moneymaker” Tomato to Potato Spindle Tuber Viroid Infection from Tolerance to Lethal Systemic Necrosis, Accompanied by Up-Regulation of miR398a-3p and Reactive Oxygen Species

Version 1 : Received: 27 November 2018 / Approved: 28 November 2018 / Online: 28 November 2018 (06:50:07 CET)

How to cite: Suzuki, T.; Ikeda, S.; Kasai, A.; Taneda, A.; Sugawara, K.; Fujibayashi, M.; Okuta, M.; Maeda, H.; Sano, T. RNAi-Mediated Down-Regulation of Dicer-Like 2 and 4 Changes the Response of “Moneymaker” Tomato to Potato Spindle Tuber Viroid Infection from Tolerance to Lethal Systemic Necrosis, Accompanied by Up-Regulation of miR398a-3p and Reactive Oxygen Species. Preprints 2018, 2018110606 (doi: 10.20944/preprints201811.0606.v1). Suzuki, T.; Ikeda, S.; Kasai, A.; Taneda, A.; Sugawara, K.; Fujibayashi, M.; Okuta, M.; Maeda, H.; Sano, T. RNAi-Mediated Down-Regulation of Dicer-Like 2 and 4 Changes the Response of “Moneymaker” Tomato to Potato Spindle Tuber Viroid Infection from Tolerance to Lethal Systemic Necrosis, Accompanied by Up-Regulation of miR398a-3p and Reactive Oxygen Species. Preprints 2018, 2018110606 (doi: 10.20944/preprints201811.0606.v1).

Abstract

To examine the role of RNA silencing in defense against viroid, a Dicer-like 2 and 4 (DCL2&4)—double knockdown transgenic tomato line 72E was created. The expression of endogenous DCL2 and DCL4 in line 72E decreased to about a half of the empty cassette line EC. When challenged with potato spindle tuber viroid (PSTVd), 72E allowed significantly higher level of PSTVd accumulation early in infection and showed lethal systemic necrosis. The size distribution of PSTVd-derived small RNA was significantly changed: the numbers of 21 and 22 nucleotides (nt) species in line 72E was approximately 66.7% and 5% of those in line EC, respectively. Conversely, the numbers of 24-nt species increased by 1100%. Furthermore, expression of miR398a-3p and miR398 increased 770–868% in the PSTVd-infected 72E, compared to the PSTVd-infected EC. In parallel, superoxide dismutase (SOD1) in PSTVd-infected 72E showed higher expression levels. In concert with miR398a-3p, SOD1 controls detoxification of reactive oxygen species (ROS) generated in cells. Since high levels of ROS production and its scavenging activity were observed in PSTVd-infected 72E, the lack of full-activity of DCLs was thought to have made the plant incapable to control excessive ROS production and thus resulted in to develop lethal systemic necrosis.

Subject Areas

viroid; pathogenicity; RNA silencing; Dicer-like proteins; small interfering RNA; microRNA398; microRNA398a-3p; superoxide dismutase 1; reactive oxygen species; systemic necrosis

Comments (0)

We encourage comments and feedback from a broad range of readers. See criteria for comments and our diversity statement.

Leave a public comment
Send a private comment to the author(s)
Views 0
Downloads 0
Comments 0
Metrics 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.