T4 DNA连接酶介导的5'RACE法克隆大鼠Nor1全长cDNA

目的:克隆75AEST全长cDNA序列。方法:抽提在25mmol/LKCl条件下培养7d的大鼠小脑颗粒神经元的总RNA后,用DNA连接酶介导的5'RACE法克隆75A表达序列标签(EST)cDNA5'端未知序列,其产物亚克隆到pGEM-Teasy后进行序列测定以及同源性分性。结果:首轮5'RACE扩增出2.5kb序列后,75AEST鉴定为神经来源孤儿受体1(Nor1)基因的部分序列;再经过二次轮5'RACE,我们首次克隆Nor-1的全长cDNA序列。结论:T₄DNA连接酶介导的5'RACE是一种效率较高的克隆mRNA5'端未知序列的好方法,为进一步研究Nor1在小脑颗粒神经元存活或分化过程中的作用奠定基础。

Cloning of the full-length rat Nor1 cDNA using T4 DNA-ligase-mediated 5'RACE

AIM: To clone the full-length of 75A EST. METHODS: After the extraction of total RNA from primary cultured rat cerebellar granule cell of 7DIV in the medium containing 25 mmol/L KCl, T_4 DNA ligase-mediated 5' RACE was used to retrieve 5' unknown sequence of 75A EST, and the first round 5' RACE PCR product was subcloned into pGEM-T easy vector for sequence and homogeneous analysis. RESULTS: The first round of 5' RACE produce a 2.5 kb band, and 75A EST was identified to be partial sequence of Neuron-derived orphan receptor (Nor1) gene. After two more rounds RACE, we firstly cloned the full-length of Nor-1 cDNA. CONCLUSION: T_4 DNA ligase mediated 5' RACE is an efficient method to retrieve information about the 5' termini of mRNAs, and lay a foundation for further study which role Nor1 play in the cerebellar granule cell differentiation or survive.