Characterization of a second member of the sentrin family of ubiquitin-like proteins
Characterization of a second member of the sentrin family of ubiquitin-like proteins
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DOI：
10.1074/jbc.273.18.11349
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发表时间：
1998-05-01
影响因子：
4.8
通讯作者：
Yeh, ETH
中科院分区：
文献类型：
--
作者：
Kamitani, T;Kito, K;Yeh, ETH
Sentrin是一种新的泛素样蛋白，它能以类似于泛素化的方式与其他蛋白质结合。另外两个编码与Sentrin高度同源的蛋白质的cDNA序列已被GenBank（TM）报道，尚不清楚这些Sentrin样蛋白是否也能作为蛋白质修饰剂发挥功能。在这份报告中，详细描述了sentrin家族的第二个成员。Sentrin-2是一种95个氨基酸的多肽，与sentrin-1有46%的同一性和66%的同源性。北方印迹分析显示，sentrin-2的信息在所有组织中表达，但在肝脏和胎盘中几乎检测不到。通过在COS细胞中表达血凝素表位标记的sentrin-2来测试sentrin-2与其他蛋白质缀合的能力。Western blot分析表明，sentrin-2可以转移到其他蛋白质的模式类似的sentrin-1的共轭和具有类似的C-末端加工。我们进一步表明，sentrin-1和sentrin-2可以共价修饰RanGAP 1，一种与核转运密切相关的Ran GTP酶激活蛋白。免疫细胞化学分析表明，sentrin-2衍生物在细胞核中高度富集。总之，我们的结果表明，sentrin-2是sentrin化途径的另一种蛋白质修饰剂。
Sentrin is a novel ubiquitin-like protein that can be conjugated to other proteins in a manner analogous to ubiquitination, Two additional cDNA sequences that encode proteins highly homologous to sentrin have been reported to GenBank(TM), It is not known whether these sentrin-like proteins could also function as protein modifiers. In this report, a second member of the sentrin family was characterized in detail. Sentrin-2 is a 95-amino acid polypeptide that is 46% identical and 66% homologous to sentrin-1. Northern blot analysis showed that the sentrin-2 message was expressed in all tissues, but was barely detectable in the liver and placenta. The ability of sentrin-2 to conjugate to other proteins was tested by expressing hemagglutinin epitope-tagged sentrin-2 in COS cells. Western blot analysis showed that sentrin-2 could be transferred to other proteins in a pattern similar to that of sentrin-1 conjugation and had similar C-terminal processing. We further showed that both sentrin-1 and sentrin-2 could covalently modify RanGAP1, a Ran GTPase-activating protein critically involved in nuclear transport. Immunocytochemical analysis showed that sentrin-2 derivatives were highly enriched in the nucleus. Taken together, our results demonstrate that sentrin-2 is another protein modifier for the sentrinization pathway.