Dynamic ligand modulation of EPO receptor pools, and dysregulation by polycythemia-associated EPOR alleles.
Dynamic ligand modulation of EPO receptor pools, and dysregulation by polycythemia-associated EPOR alleles.
复制标题
EPO 受体库的动态配体调节以及红细胞增多症相关 EPOR 等位基因的失调。
DOI：
10.1371/journal.pone.0029064
复制
发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Wojchowski DM
中科院分区：
文献类型：
--
作者：
Singh S;Verma R;Pradeep A;Leu K;Mortensen RB;Young PR;Oyasu M;Schatz PJ;Green JM;Wojchowski DM
促红细胞生成素（EPO）及其细胞表面受体（EPOR）对于红细胞生成至关重要;可以调节非红细胞靶组织;并据报道影响某些癌症的进展。然而，EPOR表达和运输的基础研究受到低水平EPOR发生和抗EPOR抗体特异性有限的阻碍。因此，EPOR生物学的这些方面没有很好地定义，红细胞增多症相关的突变EPOR等位基因的作用也没有很好地定义。使用针对细胞内、PY-活化和细胞外EPOR结构域的新型兔单克隆抗体，首先明确定义了红系祖细胞中内源性hEPOR的以下性质。1)高-只有当EPO受到限制时，Mr EPOR形式才变得明显表达。2)EPOR-68 K加上-70K物质依次积累，EPOR-70 K包含表观细胞表面EPOR群体。3)布雷菲德菌素A、N-聚糖酶和相关分析指出EPOR-68 K是核心糖基化的细胞内EPOR库（中等大小）。4)与最近的报道相反，EPOR向内运输（在UT 7 epo细胞和原代成红细胞中）显示为明显的配体依赖性。除此之外，当红细胞增多症患者所携带的C-末端截短的hEPOR-T突变等位基因与EPO依赖性红系祖细胞中的野生型EPOR共表达时，几个特定事件发生改变。首先，EPOR-T等位基因在EPO激发后持续活化，但也经历明显的转换（转换为低Mr EPOR产物）。此外，在指数细胞生长期间，EPOR-T种类变得过度代表和超活化。有趣的是，EPOR-T表达还导致内源性野生型EPOR的EPO剂量依赖性损失（因此，EPOR C-末端介导的负反馈效应的压制）。因此，提供了关于调节EPOR表达和运输的新知识，以及对突变的EPOR-T红细胞增多症等位基因失调的EPOR-T受体的机制的新见解。值得注意的是，特定的新工具也被表征用于EPOR表达、活化、作用和代谢的研究。
Erythropoietin (EPO) and its cell surface receptor (EPOR) are essential for erythropoiesis; can modulate non-erythroid target tissues; and have been reported to affect the progression of certain cancers. Basic studies of EPOR expression and trafficking, however, have been hindered by low-level EPOR occurrence, and the limited specificity of anti-EPOR antibodies. Consequently, these aspects of EPOR biology are not well defined, nor are actions of polycythemia- associated mutated EPOR alleles. Using novel rabbit monoclonal antibodies to intracellular, PY- activated and extracellular EPOR domains, the following properties of the endogenous hEPOR in erythroid progenitors first are unambiguously defined. 1) High- Mr EPOR forms become obviously expressed only when EPO is limited. 2) EPOR-68K plus -70K species sequentially accumulate, and EPOR-70K comprises an apparent cell surface EPOR population. 3) Brefeldin A, N-glycanase and associated analyses point to EPOR-68K as a core-glycosylated intracellular EPOR pool (of modest size). 4) In contrast to recent reports, EPOR inward trafficking is shown (in UT7epo cells, and primary proerythroblasts) to be sharply ligand-dependent. Beyond this, when C-terminal truncated hEPOR-T mutant alleles as harbored by polycythemia patients are co-expressed with the wild-type EPOR in EPO-dependent erythroid progenitors, several specific events become altered. First, EPOR-T alleles are persistently activated upon EPO- challenge, yet are also subject to apparent turn-over (to low-Mr EPOR products). Furthermore, during exponential cell growth EPOR-T species become both over-represented, and hyper-activated. Interestingly, EPOR-T expression also results in an EPO dose-dependent loss of endogenous wild-type EPOR's (and, therefore, a squelching of EPOR C-terminal- mediated negative feedback effects). New knowledge concerning regulated EPOR expression and trafficking therefore is provided, together with new insight into mechanisms via which mutated EPOR-T polycythemia alleles dysregulate the erythron. Notably, specific new tools also are characterized for studies of EPOR expression, activation, action and metabolism.
登录
查看更多内容
DOI：
10.1016/j.bbadis.2005.03.003
发表时间：
2005-04-15
影响因子：
6.2
作者：
Arcasoy, MO;Karayal, AF
通讯作者：
Karayal, AF
影响因子：
4.8
作者：
Chen, Jinglong;Olsen, Jane;Young, Ian G.
通讯作者：
Young, Ian G.
AML1-ETO9a 与 C-KIT 过度表达/突变相关，表明 t(8;21) 急性髓系白血病-M2 的疾病结果不佳
影响因子：
11.4
作者：
Jiao, B.;Wu, C-F;Chen, S-J
通讯作者：
Chen, S-J
影响因子：
3.3
作者：
Chun, Justin;Shapovalova, Zoya;Melancon, Paul
通讯作者：
Melancon, Paul
影响因子：
4.8
作者：
Martinez-Nunez, Rocio T.;Louafi, Fethi;Sanchez-Elsner, Tilman
通讯作者：
Sanchez-Elsner, Tilman