摘要
目的:分析受体酪氨酸蛋白激酶(receptor tyrosine kinases,RTKs)亚家族TAM(Tyro3、Axl和Mer)在大鼠脑中的表达模式及细胞定位,并进一步探讨TAM在脑中表达的意义。方法:分别提取出生后3、9、15、30及52 d龄SD大鼠脑组织总RNA和总蛋白,实时定量PCR(real time quantitative PCR)检测TAM mRNA水平的表达,Westernblotting检测TAM蛋白水平的表达,免疫组织化学染色检测Tyro3蛋白在大鼠脑中的定位。结果:Tyro3 mRNA在脑的表达水平显著高于Axl及Mer,从生后15 d龄开始有明显表达,随后呈现明显上调趋势,至生后52 d龄Tyro3mRNA的表达量达到15 d的3.2倍。Tyro3蛋白的表达水平也呈明显上调趋势,从生后15 d龄开始到52 d龄,Ty-ro3蛋白的表达量显著增高,生后52 d龄Tyro3蛋白的表达量是15 d龄的1.3倍;免疫组织化学染色结果显示Ty-ro3蛋白主要分布于皮层细胞,梨状皮层和海马区细胞内有Tyro3蛋白的强阳性着色;在亚细胞水平,Tyro3蛋白存在于锥体神经元的胞质和树突部分。结论:TAM受体酪氨酸蛋白激酶家族Tyro3基因及其编码产物在大鼠脑组织发育过程中呈阶段性上调表达,并且Tyro3蛋白在海马神经元胞体及轴突有显著高表达,提示Tyro3蛋白可能通过受体酪氨酸蛋白激酶信号转导途径参与了脑突触功能的调控。
Objective：To detect the expression patterns and localization of the Tyro3,Axl,and Mer（TAM） receptor tyrosine kinases in the rat brain,and to understand the significance of this recepto family in the brain.Methods：Sprague Dawley rats aged P3（day 3 of postnatal development）,P9,P15,P30 and P52 were anesthetized and their brains removed.Real time quantitative PCR was used to deter mine mRNA expression levels of TAM.Western blotting was applied to analyze protein expression level of TAM peptides.The immunohistochemical stainings of Tyro3 protein in adult rat brains were detected by the avidin-biotin-peroxidase complex method.Results：Tyro3 was the most highly expressed and wide ly distributed receptor among TAM family.Its mRNA level increased dramatically during the second post natal week,reached at the highest level by P30,and remained at that level in the adult.The relative ex pression quantitative of Tyro3 mRNA in the adult rat brain increased about 3.2-fold than that at P15 stage.The expression of Tyro3 protein was detected faintly at early stage,gradually increased from P15,and reached maximal levels at adult stage.The relative density of immunoreactive product of Tyro3 pep tide in the rat brain was up-regulated 1.3-fold from P15 to adult（P52）.Immunohistochemical staining demonstrated that Tyro3 protein was detected in the majority of cells of all the cortical layers.Strong sig nals were observed in the piriform cortex and the hippocampus.At the subcellular level,Tyro3 was de tected both in the soma and dendrites of pyramidal neurons.Conclusion：The results imply that Tyro3 i the main TAM receptor tyrosine kinase expressed in adult rat brain that modulates signaling cascades in fluencing synaptic function in the brain.
出处
《北京大学学报（医学版）》
CAS
CSCD
北大核心
2012年第6期905-910,共6页
Journal of Peking University:Health Sciences
作者简介
Corresponding author’s:郭睿,e-mail,guoruipumc@yahoo.com.cn.
