A novel lipid raft-associated glycoprotein, TEC-21, activates rat basophilic leukemia cells independently of the type 1 Fc epsilon receptor.
A novel lipid raft-associated glycoprotein, TEC-21, activates rat basophilic leukemia cells independently of the type 1 Fc epsilon receptor.
复制标题
一种新型脂筏相关糖蛋白 TEC-21 可独立于 1 型 Fc epsilon 受体激活大鼠嗜碱性白血病细胞。
作者：
I. Halova;L. Draberova;P. Dráber
最近的数据表明，通过1型Fc γ受体（Fc γ RI）和其他免疫受体的信号转导的启动在空间上被限制到脂筏。为了更好地理解这些结构的复杂性和功能，我们制备了针对大鼠嗜碱性白血病细胞系RBL-2 H3的脂筏的mAb，该细胞系被广泛用于分析Fc β RI介导的活化。其中一种抗体被发现识别一种新的糖基磷脂酰肌醇锚定的质膜糖蛋白，命名为TEC-21，含有一个富含半胱氨酸的结构域，与尿激酶纤溶酶原激活物受体/Ly-6/蛇神经毒素家族中发现的结构域同源。TEC-21在RBL-2 H3细胞的表面上是丰富的（>10（6）分子/细胞），但在除睾丸之外的许多大鼠组织中不存在。TEC-21在RBL-2 H3细胞上的聚集诱导了包括Syk激酶和LAT适配器在内的几种底物的酪氨酸磷酸化、钙流和分泌组分的释放的快速增加。在通过Fc β RI活化的细胞中观察到类似但更深刻的活化事件。然而，TEC-21的聚集并不诱导IgE-Fc β RI复合物的密度、Fc β RI β和γ亚基的酪氨酸磷酸化以及林恩激酶的共聚集的变化。在RBL-2 H3细胞的Fc ε RI（-）突变体中也观察到TEC-21诱导的活化事件。因此，TEC-21是RBL-2 H3细胞的一种新的脂筏组分，其聚集诱导不依赖于Fc β RI的活化。
Recent data suggest that initiation of signal transduction via type 1 Fc epsilon receptor (Fc epsilon RI) and other immunoreceptors is spatially constrained to lipid rafts. In order to better understand the complexity and function of these structures, we prepared mAb against lipid rafts from the rat basophilic leukemia cell line, RBL-2H3, which is extensively used for analysis of Fc epsilon RI-mediated activation. One of the antibodies was found to recognize a novel glycosylphosphatidylinositol-anchored plasma membrane glycoprotein of 250 amino acids, designated TEC-21, containing a cysteine-rich domain homologous to those found in the urokinase plasminogen activator receptor/Ly-6/snake neurotoxin family. TEC-21 is abundant on the surface of RBL-2H3 cells (>10 (6) molecules/cell), but is absent in numerous rat tissues except for testes. Aggregation of TEC-21 on RBL-2H3 cells induced a rapid increase in tyrosine phosphorylation of several substrates including Syk kinase and LAT adaptor, calcium flux, and release of secretory components. Similar but more profound activation events were observed in cells activated via Fc epsilon RI. However, aggregation of TEC-21 did not induce changes in density of IgE-Fc epsilon RI complexes, tyrosine phosphorylation of Fc epsilon RI beta and gamma subunits, and co-aggregation of Lyn kinase. TEC-21-induced activation events were also observed in Fc epsilon RI(-) mutants of RBL-2H3 cells. Thus, TEC-21 is a novel lipid raft component of RBL-2H3 cells whose aggregation induces activation independently of Fc epsilon RI.
影响因子：
32.4
作者：
R. Xavier;Todd Brennan;Qingqin Li;Christine McCormack;B. Seed
通讯作者：
R. Xavier;Todd Brennan;Qingqin Li;Christine McCormack;B. Seed
影响因子：
4
作者：
D. Holowka;Erin D. Sheets;Barbara Baird
通讯作者：
D. Holowka;Erin D. Sheets;Barbara Baird
构建糖基磷脂酰肌醇锚附着的合成信号。
DOI：
--
发表时间：
1993
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Coyne,KE;Crisci,A;Lublin,DM
通讯作者：
Lublin,DM