Histone methylation, which is mediated by the histone lysine (K) methyltransferases (HKMTases), is a mechanism associated with many pathways in eukaryotes. Most HKMTases have a conserved SET (Su(var) 3-9,E(z),Trithorax) domain, while the HKMTases with SET domains are called the SET domain group (SDG) proteins. In plants, only SDG proteins can work as HKMTases. In this review, we introduced the classification of SDG family proteins in plants and the structural characteristics of each subfamily, surmise the functions of SDG family members in plant growth and development processes, including pollen and female gametophyte development, flowering, plant morphology and the responses to stresses. This review will help researchers better understand the SDG proteins and histone methylation in plants and lay a basic foundation for further studies on SDG proteins.

中文翻译：

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植物中组蛋白赖氨酸甲基化相关的SET结构域基团蛋白的功能。

组蛋白赖氨酸（K）甲基转移酶（HKMTases）介导的组蛋白甲基化是一种与真核生物中许多途径相关的机制。大多数HKMTase具有保守的SET（Su（var）3-9，E（z），Trithorax）结构域，而带有SET结构域的HKMTase称为SET结构域组（SDG）蛋白。在植物中，只有SDG蛋白可以用作HKMTase。在这篇综述中，我们介绍了植物中SDG家族蛋白的分类和每个亚科的结构特征，概述了SDG家族成员在植物生长和发育过程中的功能，包括花粉和雌配子体发育，开花，植物形态和响应强调。