COP9信号体(CSN)是在高等真核生物中发现的保守蛋白质复合物,由八个亚基组成,在调节植物生长发育的各种过程中起着至关重要的作用。在这些亚基中,CSN2是COP9信号体复合物中最保守的成分之一。尽管它之前在其他物种中被鉴定,其在水稻(水稻)中的具体功能仍然知之甚少。在这项研究中,我们使用基因编辑CRISPR/Cas9技术和过表达技术研究了CSN2在水稻中的作用。我们创建了两种类型的突变体:ospsn2突变体和OsCSN2-OE突变体,在水稻的背景下,并产生了OsCSN2的点突变体(OsCSN2K64E,OsCSN2K67E,OsCSN2K71E和OsCSN2K104E)进一步探讨OsCSN2的调控功能。对产生的突变体的植物进行表型观察和基因表达分析,跟踪它们从幼苗到抽穗阶段的生长。结果表明,在野生型和突变体植株的早期,OsCSN2的缺失和修饰对植株的生长发育影响有限。然而,随着植物生长到60天,出现了显著的差异。与OsCSN2-OE突变植物相比,OsCSN2点突变体显示出增加的分till,已经处于分till阶段。另一方面,OsCSN2点突变体已经进展到抽穗和开花期,较短的植物。这些结果,以及OsCSN2蛋白的功能预测,表明第64届的变化,67,第71名,OsCSN2的第104个氨基酸影响其泛素化位点,影响CSN的泛素化功能,从而影响DELLA蛋白SLR1的降解。一起来看,可以推测OsCSN2通过影响CSN中转录因子SLR1的功能调控,在GA和BR通路中起关键作用,从而影响水稻的生长发育和分耕数量。
The COP9 signalosome (CSN) is a conserved protein complex found in higher eukaryotes, consisting of eight subunits, and it plays a crucial role in regulating various processes of plant growth and development. Among these subunits, CSN2 is one of the most conserved components within the COP9 signalosome complex. Despite its prior identification in other species, its specific function in Oryza sativa L. (Rice) has remained poorly understood. In this study, we investigated the role of CSN2 in rice using gene editing CRISPR/Cas9 technology and overexpression techniques. We created two types of mutants: the oscsn2 mutant and the OsCSN2-OE mutant, both in the background of rice, and also generated point mutants of OsCSN2 (OsCSN2K64E, OsCSN2K67E, OsCSN2K71E and OsCSN2K104E) to further explore the regulatory function of OsCSN2. Phenotypic observation and gene expression analysis were conducted on plants from the generated mutants, tracking their growth from the seedling to the heading stages. The results showed that the loss and modification of OsCSN2 had limited effects on plant growth and development during the early stages of both the wild-type and mutant plants. However, as the plants grew to 60 days, significant differences emerged. The OsCSN2 point mutants exhibited increased tillering compared to the OsCSN2-OE mutant plants, which were already at the tillering stage. On the other hand, the OsCSN2 point mutant had already progressed to the heading and flowering stages, with the shorter plants. These results, along with functional predictions of the OsCSN2 protein, indicated that changes in the 64th, 67th, 71st, and 104th amino acids of OsCSN2 affected its ubiquitination site, influencing the ubiquitination function of CSN and consequently impacting the degradation of the DELLA protein SLR1. Taken together, it can be speculated that OsCSN2 plays a key role in GA and BR pathways by influencing the functional regulation of the transcription factor SLR1 in CSN, thereby affecting the growth and development of rice and the number of tillers.