Departamento de Recursos Naturais, Ambiente e Território (DRAT)/Centro de Botânica Aplicada à Agricultura (CBAA), Institute of Agronomy, University of Lisbon, Tapada da Ajuda, 1349-017, Lisbon, Portugal.
Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB) Campus Universitat Autonoma de Barcelona (UAB), Edificio Center for Research in Agricultural Genomics (CRAG), Bellaterra, Cerdanyola del Vallès, 08193, Barcelona, Spain.
J Integr Plant Biol. 2015 Jun;57(6):591-601. doi: 10.1111/jipb.12296. Epub 2015 Jan 29.
Peroxiredoxins (Prx) catalyse the reduction of hydrogen peroxide (H2O2) and, in association with catalases and other peroxidases, may participate in signal transduction by regulating intercellular H2O2 concentration that in turn can control gene transcription and cell signaling. Using virus-induced-gene-silencing (VIGS), 2-Cys Peroxiredoxin (2CysPrx) family and type-II Peroxiredoxin B (PrxIIB) gene were silenced in Nicotiana benthamiana, to study the impact that the loss of function of each Prx would have in the antioxidant system under control (22 °C) and severe heat stress conditions (48 °C). The results showed that both Prxs, although in different organelles, influence the regeneration of ascorbate to a significant extent, but with different purposes. 2CysPrx affects abscisic acid (ABA) biosynthesis through ascorbate, while PrxIIB does it probably through the xanthophyll cycle. Moreover, 2CysPrx is key in H2O2 scavenging and in consequence in the regulation of ABA signaling downstream of reactive oxygen species and PrxIIB provides an important assistance for H2O2 peroxisome scavenges.
过氧化物酶（Prx）催化过氧化氢（H2O2）的还原，并且与过氧化氢酶和其他过氧化物酶一起，可能通过调节细胞间 H2O2 浓度参与信号转导，而 H2O2 浓度又可以控制基因转录和细胞信号。通过病毒诱导的基因沉默（VIGS），在本氏烟中沉默了 2-半胱氨酸过氧化物酶（2CysPrx）家族和 II 型过氧化物酶 B（PrxIIB）基因，以研究每种 Prx 功能丧失对在对照（22°C）和严重热应激条件（48°C）下抗氧化系统的影响。结果表明，尽管这两种 Prx 位于不同的细胞器中，但它们都在很大程度上影响抗坏血酸的再生，但目的不同。2CysPrx 通过抗坏血酸影响脱落酸（ABA）的生物合成，而 PrxIIB 可能通过叶黄素循环来实现。此外，2CysPrx 是清除 H2O2 和因此调控活性氧下游 ABA 信号的关键，而 PrxIIB 为过氧化物酶体清除 H2O2 提供了重要帮助。
