ARIP1,2 mRNA及其蛋白在小鼠脑组织表达和分布的比较研究

Expression and localization of mRNA and protein of activin receptor-interacting protein 1 and 2 in mouse brain

目的比较新发现的激活素受体相互作用蛋白1,2(ARIP1,2)在小鼠脑组织的表达与分布。方法采用Northern杂交检测ARIP1,2 mRNA,Western杂交及免疫组化染色检测ARIP1,2蛋白。结果Northern杂交显示ARIP1,2 mRNA在小鼠组织中的表达形式明显不同,ARIP1主要在脑组织表达,ARIP2组织表达广泛。Western杂交进一步揭示ARIP1在大脑、小脑、海马、下丘脑及垂体表达,而ARIP2在大脑、小脑、海马、下丘脑、垂体及脾脏均有不同程度表达。免疫组化染色显示,ARIP1,2成熟蛋白在大脑、小脑及垂体均有表达,ARIP1在大脑和小脑皮质主要表达在小细胞神经元,而ARIP2主要表达在大细胞神经元。ARIP1在神经垂体和腺垂体表达水平明显高于ARIP2。结论ARIP1,2均表达于脑和垂体,但其表达的细胞类型和强度明显不同,这种差异可能与其在神经细胞中介导激活素生物学活性差异有关。

Objective To compare the distributions and expressions of activin receptor-interacting protein 1 and 2 （ARIP1,2）in mouse brain. Method mRNA expressions of ARIP1,2 were analyzed by Northern blotting and their protein localizations were detected by Western blotting and immunohistochemical staining. Results Northern blotting showed that the expressions of ARIP1 and 2 mRNA were very different in mouse tissues. ARIP1 mRNA was highly expressed in brain, in contrast, ARIP2 mRNA was widely expressed in tissuses. Furthermore, Western blotting revealed that ARIP1 was expressed in cerebrum, cerebellum, hippocampus, hypothalamus and pituitary, and ARIP2 was expressed in cerebrum, cerebellum, hippocampu, hypothalamus, pituitary and spleen. The immunohistochemical staining showed that both mature ARIP1 and 2 proteins were detectable in eerebrnm, cerebellum, choroid and pituitary. In cerebral cortex and cerebellar cortex, ARIP1 was mainly expressed in the parvicellular neurons, but ARIP2 was high expressed in the megaeellular neurons. The immunoreactivity of ARIP1 was stronger than that of ARIP2 in neurohypophysis and adenohypophysis. Conclusion Both ARIP1 and 2 was expressed in brain and pituitary, but the types of positive cells and intensity of them were obviously different. The difference may be associate with the histological specificity of activin action in different cells.