Ferritin associates with marginal band microtubules
Ferritin associates with marginal band microtubules
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DOI：
10.1016/j.yexcr.2007.02.021
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发表时间：
2007-05-01
影响因子：
3.7
通讯作者：
Propst, Friedrich
中科院分区：
文献类型：
--
作者：
Infante, Anthony A.;Infante, Dzintra;Propst, Friedrich
我们通过生化研究和免疫荧光来表征鸡红细胞和人血小板铁蛋白。红细胞铁蛋白被发现是 H-铁蛋白亚基的均聚物，能抵抗蛋白酶 K 消化，热稳定且含有铁。在成熟的鸡红细胞和人血小板中，铁蛋白位于边缘带，即环形外周微管束，并显示出真正的微管相关蛋白（如 tau）的特性。红细胞铁蛋白与边缘带的关联通过温度诱导的微管拆卸-重组得到证实。在红细胞分化过程中，铁蛋白在边缘带形成过程中与聚结微管共定位。此外，在成熟红细胞的细胞核中发现了铁蛋白，但在骨髓红细胞前体细胞核中未检测到。这些结果表明，铁蛋白在边缘带形成中具有功能，并且可能通过在成熟红细胞中隔离铁来保护边缘带免受活性氧的破坏性影响。此外，我们的数据表明，铁蛋白和 Synolin（一种先前鉴定的红细胞微管相关蛋白）是相同的。核铁蛋白可能有助于转录沉默，或者构成铁蛋白库。 (c) 2007 Elsevier Inc. 保留所有权利。
We characterized chicken erythrocyte and human platelet ferritin by biochemical studies and immunofluorescence. Erythrocyte ferritin was found to be a homopolymer of H-ferritin subunits, resistant to proteinase K digestion, heat stable, and contained iron. In mature chicken erythrocytes and human platelets, ferritin was localized at the marginal band, a ring-shaped peripheral microtubule bundle, and displayed properties of bona fide microtubule-associated proteins such as tau. Red blood cell ferritin association with the marginal band was confirmed by temperature-induced disassembly-reassembly of microtubules. During erythrocyte differentiation, ferritin co-localized with coalescing microtubules during marginal band formation. In addition, ferritin was found in the nuclei of mature erythrocytes, but was not detectable in those of bone marrow erythrocyte precursors. These results suggest that ferritin has a function in marginal band formation and possibly in protection of the marginal band from damaging effects of reactive oxygen species by sequestering iron in the mature erythrocyte. Moreover, our data suggest that ferritin and syncolin, a previously identified erythrocyte microtubule-associated protein, are identical. Nuclear ferritin might contribute to transcriptional silencing or, alternatively, constitute a ferritin reservoir. (c) 2007 Elsevier Inc. All rights reserved.