Mashima Ryuichi
Department of Microbiology and Immunology, Keio University, School of Medicine, Shinjuku-ku, Tokyo, Japan.
Immunology. 2015 Jul;145(3):323-33. doi: 10.1111/imm.12468. Epub 2015 May 19.
miR-155 is involved in non-coding microRNAs found in humans, mice and chickens of which the sequence is conserved. Historically, miR-155 was identified as a B-cell integration cluster (bic), which induces B-cell leucosis in chickens, by its activation through viral promoter insertion. Subsequent studies have shown that transgenic mice expressing miR-155 in B cells generated lymphoma, showing that miR-155 is oncogenic. Biochemical investigation identifies many substrates of miR-155, and one of them in B cells and macrophages is the SH2-domain containing inositol-5'-phosphatase 1. A deficiency of miR-155 in the immune system causes attenuated immune functions. Clinically, several types of malignancy including diffuse large B-cell lymphoma have high miR-155 expression levels.
miR-155是在人类、小鼠和鸡中发现的非编码微小RNA，其序列是保守的。历史上，miR-155被鉴定为B细胞整合簇（bic），它通过病毒启动子插入激活，可诱导鸡的B细胞白血病。随后的研究表明，在B细胞中表达miR-155的转基因小鼠会产生淋巴瘤，这表明miR-155具有致癌性。生化研究确定了miR-155的许多底物，其中之一在B细胞和巨噬细胞中是含SH2结构域的肌醇-5'-磷酸酶1。免疫系统中miR-155的缺乏会导致免疫功能减弱。临床上，包括弥漫性大B细胞淋巴瘤在内的几种恶性肿瘤都有较高的miR-155表达水平。
