Features of the Parkin/ariadne-like ubiquitin ligase, HHARI, that regulate its interaction with the ubiquitin-conjugating enzyme, UbcH7
Features of the Parkin/ariadne-like ubiquitin ligase, HHARI, that regulate its interaction with the ubiquitin-conjugating enzyme, UbcH7
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DOI：
10.1074/jbc.m011028200
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发表时间：
2001-06-01
影响因子：
4.8
通讯作者：
Robinson, PA
中科院分区：
文献类型：
--
作者：
Ardley, HC;Tan, NGS;Robinson, PA
我们最近报道了一种含有RING指的蛋白质HHARI的鉴定（Drosophiba ariadne的人类同源物），其在体外与人泛素缀合酶UbcH 7结合。我们现在证明HHAR 1在哺乳动物细胞中与UbcH 7相互作用并共定位，特别是在核周区。我们进一步定义了HHAR 1的最小相互作用区域，其包含残基186-254，鉴定了相互作用所必需的单个氨基酸残基，并确定了RING 1指和IBR（RING指之间）结构域之间的距离对维持结合至关重要。我们还确定，HHARI的RING 1指不能被泛素-蛋白连接酶组分c-CBL或Parkin的高度同源的RING指结构域取代，尽管它们在结构上相似，并且它们具有独立的结合UbcH 7的能力。此外，HHARI的RING 1指结构域从RING-HC型突变为RING-HP型消除了与UbcH 7的相互作用。这些研究表明，非常微妙的变化，以域之间的高度保守的组件的泛素途径的调节识别可以显着影响他们的相互作用的能力。
We recently reported the identification of a RING finger-containing protein, HHARI (human homologue of Drosophiba ariadne), which binds to the human ubiquitin-conjugating enzyme UbcH7 in vitro, We now demonstrate that HHARI interacts and co-localizes with UbcH7 in mammalian cells, particularly in the perinuclear region, We have further defined a minimal interaction region of HHARI comprising residues 186-254, identified individual amino acid residues essential for the interaction, and determined that the distance between the RING1 finger and IBR (in between RING fingers) domains is critical to maintaining binding. We have also established that the RING1 finger of HHARI cannot be substituted for by the highly homologous RING finger domains of either of the ubiquitin-protein ligase components c-CBL or Parkin, despite their similarity in structure and their independent capabilities to bind UbcH7, Furthermore, mutation of the RING1 finger domain of HHARI from a RING-HC to a RING-HP type abolishes interaction with UbcH7. These studies demonstrate that very subtle changes to the domains that regulate recognition between highly conserved components of the ubiquitin pathway can dramatically affect their ability to interact.