Participation of a fusogenic protein, glyceraldehyde-3-phosphate dehydrogenase, in nuclear membrane assembly
Participation of a fusogenic protein, glyceraldehyde-3-phosphate dehydrogenase, in nuclear membrane assembly
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DOI：
10.1074/jbc.m210824200
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发表时间：
2003-05-30
影响因子：
4.8
通讯作者：
Horigome, T
中科院分区：
文献类型：
--
作者：
Nakagawa, T;Hirano, Y;Horigome, T
我们发现了一种自身免疫血清 K199，它在涉及非洲爪蟾卵提取物的无细胞系统中强烈抑制核膜组装。使用非洲爪蟾卵胞质蛋白从血清中亲和纯化四种抑制核组装的不同抗体。这些抗体识别的三种蛋白质通过部分氨基酸测序鉴定为甘油醛-3-磷酸脱氢酶(GAPDH)、果糖-1,6-二磷酸醛缩酶和染色质缩合调节因子1。已知GAPDH是一种融合蛋白。为了验证 GAPDH 参与核膜融合，应用了针对人和大鼠 GAPDH 的真实抗体，并观察到核膜融合步骤中核组装的强烈抑制。添加纯化的鸡 GAPDH 后，抗体抑制的核组装活性得以恢复。具有GAPDH 70-94氨基酸残基序列的肽，其抑制GAPDH诱导的磷脂囊泡融合，抑制核膜融合步骤中的核组装。我们认为 GAPDH 在非洲爪蟾卵提取物无细胞系统中核组装的膜融合步骤中起着至关重要的作用。
We found an autoimmune serum, K199, that strongly suppresses nuclear membrane assembly in a cell-free system involving a Xenopus egg extract. Four different antibodies that suppress nuclear assembly were affinity-purified from the serum using Xenopus egg cytosol proteins. Three proteins recognized by these antibodies were identified by partial amino acid sequencing to be glyceraldehyde-3-phosphate dehydrogenase (GAPDH), fructose-1,6-bisphosphate aldolase, and the regulator of chromatin condensation 1. GAPDH is known to be a fusogenic protein. To verify the participation of GAPDH in nuclear membrane fusion, authentic antibodies against human and rat GAPDH were applied, and strong suppression of nuclear assembly at the nuclear membrane fusion step was observed. The nuclear assembly activity suppressed by antibodies was recovered on the addition of purified chicken GAPDH. A peptide with the sequence of amino acid residues 70-94 of GAPDH, which inhibits GAPDH-induced phospholipid vesicle fusion, inhibited nuclear assembly at the nuclear membrane fusion step. We propose that GAPDH plays a crucial role in the membrane fusion step in nuclear assembly in a Xenopus egg extract cell-free system.