Physical association between the high-affinity IgG receptor (Fc gamma RI) and the gamma subunit of the high-affinity IgE receptor (Fc epsilon RI gamma).
Physical association between the high-affinity IgG receptor (Fc gamma RI) and the gamma subunit of the high-affinity IgE receptor (Fc epsilon RI gamma).
复制标题
高亲和力 IgG 受体 (Fc gamma RI) 与高亲和力 IgE 受体 (Fc epsilon RI gamma) 的 γ 亚基之间的物理关联。
DOI：
10.1073/pnas.90.19.8847
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发表时间：
1993
影响因子：
11.1
通讯作者：
Geha,RS
中科院分区：
文献类型：
--
作者：
Scholl,PR;Geha,RS
为了研究通过高亲和力 IgG 受体 (Fc gamma RI) 的跨膜信号传导的结构基础，检查了 THP-1 人单核细胞中 Fc gamma RI 相关蛋白的身份。溶解在 1% 毛地黄皂苷缓冲液中的 125I 标记 THP-1 细胞的抗 Fc gamma RI 单克隆抗体 (mAb) 197 免疫沉淀物被发现含有一种在还原时以 12 kDa 迁移的蛋白质。该蛋白与抗高亲和力 IgE 受体 gamma 链 (Fc epsilon RI gamma) mAb 4D8 沉淀的 12 kDa 蛋白共迁移。类似地，mAb 4D8 免疫沉淀的 70-kDa 条带与 mAb 197 免疫沉淀物中对应于 Fc gamma RI 的 70-kDa 蛋白条带共迁移。在二维非还原-还原凝胶分析中，mAb 197 和 mAb 4D8 免疫沉淀物中存在的 12-kDa 蛋白以二硫键连接的同二聚体形式迁移。在还原条件下对洋地黄皂苷免疫沉淀物的 1% Nonidet P-40 洗脱液进行分析表明，mAb 197 免疫沉淀物中存在 12-kDa 条带，该条带可用 mAb 4D8 进行再沉淀。相反，mAb 4D8 免疫沉淀物中的 70-kDa 条带可以用 mAb 197 重新沉淀。与这些发现类似，mAb 197 和 mAb 4D8 在用干扰素 γ 诱导 Fc gamma RI 表达后，从 125I 标记的人中性粒细胞的洋地黄皂苷裂解物中沉淀出 12-kDa 二硫键连接的同二聚体蛋白，但不是未刺激的中性粒细胞。 Northern印迹分析证实干扰素γ诱导的人中性粒细胞中存在Fc epsilon RI gamma mRNA。我们得出结论，Fc epsilon RI gamma 是通过免疫识别受体参与跨膜信号传导的蛋白质家族的成员，与人类细胞中的 Fc gamma RI 相关。
To investigate the structural basis of transmembrane signaling via the high-affinity IgG receptor (Fc gamma RI), the identity of Fc gamma RI-associated proteins in THP-1 human monocytic cells was examined. Anti-Fc gamma RI monoclonal antibody (mAb) 197 immunoprecipitates from 125I-labeled THP-1 cells solubilized in 1% digitonin buffer were found to contain a protein migrating at 12 kDa on reduction. This protein comigrated with the 12-kDa protein precipitated by the anti-high-affinity IgE receptor gamma chain (Fc epsilon RI gamma) mAb 4D8. Similarly, a 70-kDa band immunoprecipitated by mAb 4D8 comigrated with the 70-kDa protein band corresponding to Fc gamma RI in mAb 197 immunoprecipitates. On two-dimensional nonreducing-reducing gel analysis, the 12-kDa protein present in both mAb 197 and mAb 4D8 immunoprecipitates migrated as a disulfide-linked homodimer. Analysis of 1% Nonidet P-40 eluates of the digitonin immunoprecipitates under reducing conditions demonstrated the presence of a 12-kDa band in the mAb 197 immunoprecipitate that could be reprecipitated with mAb 4D8. Conversely, a 70-kDa band in the mAb 4D8 immunoprecipitate could be reprecipitated with mAb 197. Similar to these findings, both mAb 197 and mAb 4D8 precipitated a 12-kDa disulfide-linked homodimeric protein from digitonin lysates of 125I-labeled human neutrophils after induction of Fc gamma RI expression with interferon gamma but not from unstimulated neutrophils. Northern blot analysis confirmed the presence of Fc epsilon RI gamma mRNA in interferon gamma-induced human neutrophils. We conclude that Fc epsilon RI gamma, a member of a family of proteins implicated in transmembrane signaling via immune recognition receptors, associates with Fc gamma RI in human cells.