Wheat Thioredoxin () Associates With RD19-Like Cysteine Protease to Defend Against Stripe Rust Fungus Through Modulation of Programmed Cell Death.

Thioredoxins (Trxs) function within the antioxidant network through modulation of one or more redox reactions involved in oxidative-stress signaling. Given their function in regulating cellular redox, Trx proteins also fulfill key roles in plant immune signaling. Here, , encoding a subgroup member of the Trx family, was identified and cloned in wheat (), which was rapidly induced by f. sp. invasion and salicylic acid (SA) treatment. Overexpression of in tobacco () induced programmed cell death. Silencing of in wheat enhanced susceptibility to f. sp. in different aspects, including reactive oxygen species accumulation and pathogen-responsive or -related gene expression. Herein, we observed that the cellular concentration of SA was significantly reduced in -silenced plants, indicating that possibly regulates wheat resistance to stripe rust through a SA-associated defense signaling pathway. Using a yeast two-hybrid screen to identify TaTrxh1-interacting partners, we further show that interaction with TaCP1 (a RD19-like cysteine protease) and subsequent silencing of reduced wheat resistance to f. sp. . In total, the data presented herein demonstrate that enhances wheat resistance against f. sp. via SA-dependent resistance signaling and that TaTrxh1 interaction with TaCP1 is required for wheat resistance to stripe rust.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.