SMC1B is present in mammalian somatic cells and interacts with mitotic cohesin proteins.
SMC1B is present in mammalian somatic cells and interacts with mitotic cohesin proteins.
复制标题
SMC1b存在于哺乳动物体细胞中，并与有丝分裂粘着蛋白相互作用。
DOI：
10.1038/srep18472
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发表时间：
2015-12-17
影响因子：
4.6
通讯作者：
Musio A
中科院分区：
文献类型：
--
作者：
Mannini L;Cucco F;Quarantotti V;Amato C;Tinti M;Tana L;Frattini A;Delia D;Krantz ID;Jessberger R;Musio A
黏连蛋白是一种进化上保守的蛋白质复合物，在许多生物学过程中发挥作用：它确保忠实的染色体分离，调节基因表达和保持基因组稳定性。在哺乳动物细胞中，有丝分裂粘附素复合物由两种结构维持染色体蛋白SMC 1A和SMC 3、Kleisin蛋白RAD 21和第四个亚基STAG 1或STAG 2组成。哺乳动物中的减数分裂旁系同源物被报道为SMC 1A、RAD 21和STAG 1/STAG 2，并分别被称为SMC 1B、REC 8和STAG 3。据信，SMC 1B仅是减数分裂特异性粘附素成员，其是姐妹染色单体配对和防止端粒缩短所需的。在这里，我们表明，SMC 1B也表达在体细胞哺乳动物细胞，是一个有丝分裂凝聚素复合体的成员。此外，SMC 1B保障基因组稳定性照射后，而其消融对染色体分离没有影响。最后，出乎意料的是，SMC 1B缺失会损害基因转录，特别是在定位到簇如HOX和PCDHB的基因处。全基因组分析表明，表达变化的簇基因富集了粘附素-SMC 1B结合。
Cohesin is an evolutionarily conserved protein complex that plays a role in many biological processes: it ensures faithful chromosome segregation, regulates gene expression and preserves genome stability. In mammalian cells, the mitotic cohesin complex consists of two structural maintenance of chromosome proteins, SMC1A and SMC3, the kleisin protein RAD21 and a fourth subunit either STAG1 or STAG2. Meiotic paralogs in mammals were reported for SMC1A, RAD21 and STAG1/STAG2 and are called SMC1B, REC8 and STAG3 respectively. It is believed that SMC1B is only a meiotic-specific cohesin member, required for sister chromatid pairing and for preventing telomere shortening. Here we show that SMC1B is also expressed in somatic mammalian cells and is a member of a mitotic cohesin complex. In addition, SMC1B safeguards genome stability following irradiation whereas its ablation has no effect on chromosome segregation. Finally, unexpectedly SMC1B depletion impairs gene transcription, particularly at genes mapping to clusters such as HOX and PCDHB. Genome-wide analyses show that cluster genes changing in expression are enriched for cohesin-SMC1B binding.