PSMD4（proteasome 26S subunit， non-ATPase 4），癌症关联基因，基因ID：5710，26S蛋白酶体是一种多催化蛋白酶复合物，由2个复合物、一个20S核和一个19S调节器组成，具有高度有序的结构。20S核由4个28个不相同亚单位的环组成，2个环由7个α亚单位组成，2个环由7个β亚单位组成。19S调节器由一个碱基（包含6个ATPase亚单位和2个非ATPase亚单位）和一个LID（包含10个非ATPase亚单位）组成。蛋白酶体以高浓度分布于真核细胞，并在非溶酶体途径的ATP/泛素依赖过程中分裂肽。经修饰的蛋白酶体免疫蛋白酶体的一个基本功能是加工I类mhc肽。这个基因编码19S调节盖的一个非ATP酶亚单位。在10号和21号染色体上发现了假基因。The 26S proteasome is a multicatalytic proteinase complex with a highly ordered structure composed of 2 complexes， a 20S core and a 19S regulator. The 20S core is composed of 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. The 19S regulator is composed of a base， which contains 6 ATPase subunits and 2 non-ATPase subunits， and a lid， which contains up to 10 non-ATPase subunits. Proteasomes are distributed throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lyso。