背景回顾：Glutaredoxins (GRXs) are small oxidoreductases that can modify target protein activities through control of the redox (reduction/oxidation) state by reducing or glutathionylating disulfide bridges. 

提出问题：Although CC-type GRXs are plant specific and play important roles in many processes, the mechanisms by which they modulate the activity of target proteins in vivo are unknown. 

主要发现：In this study, we show that a maize CC-type GRX, MALE STERILE CONVERTED ANTHER1 (MSCA1), acts redundantly with two paralogues, ZmGRX2 and ZmGRX5, to modify the redox state and the activity of its putative target, the TGA transcription factor FASCIATED EAR4 (FEA4) that acts as a negative regulator of inflorescence meristem development. 

结果1-GRX三突：We used CRISPR–Cas9 to create a GRX triple knockout, resulting in severe suppression of meristem, ear and tassel growth and reduced plant height. 

结果2-GRX-FEA4-分生组织发育：We further show that GRXs regulate the redox state, DNA accessibility and transcriptional activities of FEA4, which acts downstream of MSCA1 and its paralogues to control inflorescence development. 

结论：Our findings reveal the function of GRXs in meristem development, and also provide direct evidence for GRX-mediated redox modification of target proteins in plants.

 摘 要 

谷氧还蛋白GRXs是一类小的氧化还原酶，能够通过减少或者谷胱甘肽化二硫键来控制氧化还原状态，从而影响目标蛋白的活性。尽管CC类的GRXs是植物特异的，并且在很多生物学过程中都发挥重要作用，但是其在体内影响目标蛋白活性的机制还不清楚。本文中，作者发现CC类GRX编码基因MSCA1与其两个旁系同源基因ZmGRX2和ZmGRX5冗余作用于其靶标TGA转录因子FEA4基因的氧化还原和活性调控，而FEA4基因是玉米中花序分生组织发育的负调控因子。作者利用CRISPR–Cas9创制了一个GRX三突株系，导致分生组织、雌穗和雄穗生长的严重缺陷以及植物高度的变矮。作者进一步发现GRXs调控FEA4的氧化还原状态、DNA可及性以及转录活性，从而作用于MSCA1及其旁系同源基因的下游以控制花序发育。本文的研究揭示了GRXs基因在分生组织发育中的功能，并且发现了植物中GRXs直接作用于目标蛋白的氧化还原修饰。