我们的前期研究发现，上调光呼吸乙醇酸氧化酶（GLO）可显著提高水稻高光高温双重胁迫下的光合效率，水杨酸（SA）可能参与其信号调节过程（Cui et al., 2016）。进一步研究发现，GLO可与过氧化氢酶（CAT）互作，且其互作能被SA解除，因此提出一个GLO-CAT互作/解离的动态开关模型，认为其互作/解离受环境因子动态调控，由此激发出H2O2震荡波来调节植物抗逆性反应 (Zhang et al., 2016)。但该模型还需进一步证实与完善，本项目拟深入了解：（1）GLO–CAT互作/解离的调控因子及机理；（2）互作/解离对H2O2信号通路贡献大小及可能的作用差异；（3）互作/解离与植物抗逆性的关系及机理。解答上述问题，以期确立一个具有典型物理化学特征的植物H2O2信号发生的新机理，这将对植物信号转导机理研究和光呼吸功能及作用机制研究产生重要影响，可望获得意义深远的原创性成果。

Our previous work has demonstrated that up-regulating glycolate oxidase (GLO) conferred improved photosynthesis in rice under high light & high temperature conditions, and salicylic acid (SA) may be involved in the signaling process (Cui et al., 2016). Mechanistic analyses further revealed that in both rice and Arabidopsis, GLO was able to interact with catalase (CAT), and the interaction could be deregulated by SA, such that a switch model was proposed considering that association–dissociation of GLO with CAT may serve as a potential switch to modulate intracellular H2O2 levels (Zhang et al., 2016 and unpublished data). But more evidences are needed to make the model more convincing and finalized. In this project, we aim to in depth investigate that (i) regulatory factors/mechanism for association–dissociation of the GLO–CAT complex; (ii) contribution extent of the GLO–CAT modulated H2O2 to overall H2O2 signaling pathway and its possible different roles as compared with other sources of H2O2; (iii) whether and how the association-dissociation is related with stress resistance. Answering these questions may lead to discovery of a novel H2O2 genesis pathway characteristic of classical physiochemical mechanism, which will add new contributions to both signal transduction network, and function/mechanism of photorespiration in plants.