STAG2(Stromal Antigen 2)是黏连蛋白复合体(cohesin complex)的核心亚基之一,属于STAG基因家族(包括STAG1、STAG2、STAG3)。黏连蛋白是一种环状蛋白复合物,主要功能是在细胞分裂时介导姐妹染色单体的黏连(cohesion),确保染色体正确分离,维持基因组稳定性。此外,它还参与基因转录调控、DNA损伤修复和染色质三维结构的组织。STAG家族成员的共性是均能与黏连蛋白的其他核心组分(如SMC1、SMC3、RAD21)结合,但不同成员在组织分布和功能上存在差异:STAG2广泛表达于体细胞,而STAG3仅见于生殖细胞。STAG2的典型作用位点是染色质的黏连位点,通过与其他黏连蛋白亚基协作形成环状结构,物理性包裹DNA。STAG2突变(如无义突变或移码突变)会导致黏连功能缺陷,引发染色体分离错误(非整倍体)、基因组不稳定性,这与多种癌症密切相关,如骨髓增生异常综合征(MDS)、膀胱癌和胶质母细胞瘤。STAG2失活突变还可破坏染色质环(chromatin loops)结构,影响致癌基因或抑癌基因的表达调控。当STAG2过表达时,可能过度抑制染色质动态性,干扰正常转录程序;而低表达则导致黏连不足,诱发染色体不稳定性和拷贝数变异(CNVs)。STAG2缺失的癌细胞常表现出对DNA损伤剂(如PARP抑制剂)的敏感性升高,这为靶向治疗提供了潜在策略。需要注意的是,STAG2与其他黏连蛋白亚基(如RAD21)的功能存在部分冗余,但STAG2特异性调控某些基因(如WNT信号通路相关基因)的表达,其突变可能导致发育异常或肿瘤免疫微环境改变。
The protein encoded by this gene is a subunit of the cohesin complex, which regulates the separation of sister chromatids during cell division. Targeted inactivation of this gene results in chromatid cohesion defects and aneuploidy, suggesting that genetic disruption of cohesin is a cause of aneuploidy in human cancer. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2013]
由该基因编码的蛋白质是黏着复杂,这在细胞分裂期间调节姐妹染色单体的分离的亚单位。在染色单体凝聚力缺陷和非整倍此基因的结果的靶向失活,这表明黏着的遗传破坏是整倍体的人类癌症的原因。已发现该基因编码不同亚型选择性剪接转录变异体。 [由RefSeq的,2013年9月提供]
STAG2基因(以及对应的蛋白质)的细胞分布位置:
STAG2基因的本体(GO)信息:
名称 |
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4110 Cell cycle [PATH:hsa04110] |
名称 |
---|
Cell Cycle |
Cell Cycle, Mitotic |
Cohesin Loading onto Chromatin |
Establishment of Sister Chromatid Cohesion |
M Phase |
Meiosis |
Meiotic synapsis |
Metabolism of proteins |
Mitotic Anaphase |
Mitotic Metaphase and Anaphase |
Mitotic Prometaphase |
Mitotic Telophase/Cytokinesis |
Post-translational protein modification |
Resolution of Sister Chromatid Cohesion |
S Phase |
Separation of Sister Chromatids |
SUMO E3 ligases SUMOylate target proteins |
SUMOylation |
SUMOylation of DNA damage response and repair proteins |
疾病名称 | 关系值 | NofPmids | NofSnps | 来源 |
Bladder Neoplasm | 0.120271442 | 4 | 0 | BeFree_CTD_human |
Carcinoma, Transitional Cell | 0.12 | 1 | 0 | CTD_human |
Leukemia, Megakaryoblastic, of Down Syndrome | 0.12 | 1 | 0 | CTD_human |
Myeloid Leukemia | 0.12 | 1 | 0 | CTD_human |
Amyotrophic Lateral Sclerosis | 0.002367032 | 1 | 1 | GAD |
Glioblastoma | 0.001357209 | 5 | 0 | BeFree |
Malignant neoplasm of urinary bladder | 0.000814326 | 3 | 0 | BeFree |
Carcinoma of bladder | 0.000814326 | 3 | 0 | BeFree |
Carcinogenesis | 0.000542884 | 2 | 0 | BeFree |
Ewings sarcoma | 0.000542884 | 2 | 0 | BeFree |
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