TRIM21

三分模体包含蛋白质21（TRIM21） Tripartite motif containing 21
两分子TRIM21的晶体结构。其中，两分子TRIM21C端的PRYSPRY结构域分别位于左上方和左下方。它们均与位于中央的IGHG1同质二聚体C区域结合。其中，多肽链的C端被渲染为红色，N端被渲染为蓝色
有效结构 PDB 直系同源检索：PDBe, RCSB PDB查询代码列表 2IWG
标识
代号	TRIM21; RNF81; RO52; Ro/SSA; SSA; SSA1
扩展标识	遗传学：109092 鼠基因：106657 同源基因：2365 GeneCards: TRIM21 Gene
EC编号	6.3.2.-
基因本体论描述 分子功能 · DNA binding · RNA binding · ubiquitin-protein transferase activity · protein binding · zinc ion binding · ligase activity · identical protein binding 细胞成分 · cytoplasmic mRNA processing body · nucleus · nucleoplasm · cytoplasm · cytosol · SCF ubiquitin ligase complex · ribonucleoprotein complex 生物过程 · protein polyubiquitination · protein monoubiquitination · cell cycle · protein ubiquitination · cytokine-mediated signaling pathway · protein destabilization · negative regulation of NF-kappaB transcription factor activity · regulation of type I interferon production · positive regulation of type I interferon production · negative regulation of viral transcription · innate immune response · positive regulation of cell cycle · positive regulation of viral entry into host cell · positive regulation of sequence-specific DNA binding transcription factor activity · protein autoubiquitination · interferon-gamma-mediated signaling pathway · protein trimerization · negative regulation of protein deubiquitination · negative regulation of viral release from host cell Sources: Amigo / QuickGO
RNA表达模式
更多表达数据
直系同源体
物种	人类	小鼠
Entrez	6737	20821
Ensembl	ENSG00000132109	ENSMUSG00000030966
UniProt	P19474	Q62191
mRNA序列	NM_003141	NM_001082552
蛋白序列	NP_003132	NP_001076021
基因位置	Chr 11: 4.38 – 4.39 Mb	Chr 7: 102.56 – 102.57 Mb
PubMed查询	[1]	[2]

三分模体包含蛋白质21（Tripartite motif-containing protein 21，缩写为TRIM21），亦作E3泛素化蛋白质连接酶TRIM21（E3 ubiquitin-protein ligase TRIM21），系一种由人类TRIM21基因编码的蛋白质。人们已经发现了该蛋白质的可变剪切变体，但目前仅查明了其中一种在完整状态下的性质。大部分人类组织都表达此种蛋白。

结构

TRIM21系TRIM蛋白质家族的成员。TRIM模体包含了三个锌结合结构域、一个环指结构域、一个1型B箱、一个2型B箱锌指，以及一个卷曲螺旋区域。

功能

TRIM21为一种细胞内抗体介导蛋白水解途径的细胞内抗体效应子。它会与标记感染细胞的无包膜病毒体的抗体上的免疫球蛋白G和免疫球蛋白M相连。随后，其自身发生泛素化或一个辅助因子发生泛素化。其后，TRIM21会负责引导病毒体到有蛋白酶的位置。抗体和病毒的衣壳会被蛋白酶水解，但TRIM21却不会。

TRIM21为RoSSA核糖核蛋白的一个组成成分。RoSSA还含有一条单多肽链以及一条小分子RNA（这条RNA有4种）。细胞质和细胞核中均有RoSSA粒子。

临床意义

RoSSA会与干燥综合征和全身性红斑狼疮患者体内的自身抗原反应。亦有研究者以TRIM21为基础研发新药。

拓展阅读

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