Introduction
The Su(Var)3-9, Enhancer-of-zeste and Trithorax (SET) and Myeloid, Nervy, and DEAF-1 (MYND) domain-containing (SMYD) histone methyltransferases are a family of proteins that is composed by five members in mice and humans: SMYD1, SMYD2, SMYD3, SMYD4 and SMYD5. These enzymes act on histone and non-histone targets to regulate many biological processes, including muscle development and cancer (Spellmon et al. 2015). Indeed, SMYD2 (Yi, Jiang, and Fang 2019) and SMYD3 (Bottino et al. 2020) are considered to have oncogenic properties in a myriad of cancer types, although they are dispensable for normal mouse development and adult life, probably due to its redundancy (Bagislar et al. 2016). In addition, SMYD proteins are very important for muscle physiopathology (Du, Tan, and Zhang 2014). Here, we will focus on their function in immunology, in the broadest sense of the word, including basic mechanisms and clinical conditions related to the immune system.