Apolipoprotein B is a new target of the GDNF/RET and ET-3/EDNRB signalling pathways
Apolipoprotein B is a new target of the GDNF/RET and ET-3/EDNRB signalling pathways
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DOI：
10.1111/j.1365-2982.2012.01998.x
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发表时间：
2012-10-01
影响因子：
3.5
通讯作者：
Bonora, E.
中科院分区：
文献类型：
--
作者：
Evangelisti, C.;Bianco, F.;Bonora, E.
GDNF/RET和内皮素-3 (ET-3)/EDNRB调节神经嵴源性细胞的存活、分化、迁移和增殖。尽管一些RET和EDNRB信号介质已被表征，但这两种途径的大多数靶向基因仍在很大程度上是未知的。基于先前获得的哺乳动物ECE1同源的秀丽隐杆线虫菌株突变体的数据，我们重点研究了载脂蛋白B （APOB）作为RET和EDNRB途径的新靶基因。方法在小鼠神经2a细胞（一种用于研究神经嵴源性细胞发育的体外模型）中进行Apob的分子和细胞研究，同时在小鼠中敲入hirschsprung相关突变RetC620R。Apob和Ret的沉默通过shRNA进行。关键结果GDNF/RET和ET-3/EDNRB共同诱导神经元分化，导致Neuro2a细胞系Apob活化。在RetC620R突变纯合的小鼠胚胎中，Apob表达下调，呈现严重的巨结肠表型。Ret沉默阻止Apob表达增加。MAPK P38激酶激活通过GDNF/RET信号传导在Neuro2a细胞中诱导Apob表达。Apob启动子中的p53依赖性抑制元件导致Apob表达降低。沉默载脂蛋白可降低HuD蛋白的表达。Apob是RET/EDNRB通路的一个新的下游靶点，在神经元存活和维持中发挥作用，这一点通过其对HuD表达的影响得到了证实。我们的数据为研究和确定APOB基因在严重肠道运动障碍中的作用提供了一个概念框架。
Background GDNF/RET and Endothelin-3 (ET-3)/EDNRB regulate survival, differentiation, migration, and proliferation of neural crest-derived cells. Although several RET and EDNRB signalling mediators have been characterized, most of the genes targeted by these two pathways are still largely unknown. We focused our study on apolipoprotein B (APOB) as a novel target gene of the RET and EDNRB pathways, based on previous data obtained using a Caenorhabditis elegans strain mutant for the homologue of mammalian ECE1. Methods Molecular and cellular studies of Apob were performed in the murine Neuro2a cells, an in vitro model for studying neural crest-derived cell development, along with a mouse knock-in for the Hirschsprung-associated mutation RetC620R. Silencing for Apob and Ret has been performed via shRNA. Key Results GDNF/RET and ET-3/EDNRB cooperated in inducing neuronal differentiation resulting in Apob activation in Neuro2a cell line. Apob expression was downregulated in mouse embryos homozygous for the RetC620R mutation and presenting a severe Hirschsprung phenotype. Ret silencing prevented Apob expression increase. MAPK P38 kinase activation evoked Apob expression via GDNF/RET signalling in Neuro2a cells. A p53-dependent repressor element in Apob promoter resulted in a reduced Apob expression. Silencing of Apob reduced HuD protein expression. Conclusions & Inferences Apob is a novel downstream target of the RET/EDNRB pathways with a role in neuronal survival and maintenance, as indicated by its effect on HuD expression. Our data provide a conceptual framework to investigate and establish the role of APOB gene in severe gut dysmotility.