轴突生长导向因子Sema 3A在鸡胚脊髓中的表达

为了探讨轴突生长导向因子 Sema 3 A在鸡胚脊髓中的表达 ,扩增含有 Sema 3 A编码序列的质粒并制备 RNA探针 ,应用原位杂交技术检测 Sema3 A m RNA在鸡胚不同发育期 ( E4、E6、E7、E8)脊髓中的表达。结果表明 ,在鸡胚发育的第 4d( E4) ,Sema 3 A m RNA表达在神经管周围和脊髓 ;在 E6期和 E7期 ,Sema 3 A表达在中央管周围和脊髓前角 ,以腹侧为著 ;在 E8期 ,表达主要集中在前角运动神经元 ,其它部位则信号明显较弱。结论 :Sema3 A在鸡胚不同发育期脊髓中的表达是动态的 ,呈现向腹侧集中的趋势 ;它可能在脊髓发育期轴突的投射中起着导向作用

THE EXPRESSION OF AN AXON GUIDANCE CUE SEMA 3A IN THE SPINAL CORD OF CHICK EMBRYO

To detect the expression of Sema 3A mRNA in the spinal cord of chick embryo, plasmid containing Sema 3A encoding sequence was amplified and RNA probe was produced. The expression of Sema 3A in the spinal cord of chick embryo was detected by in situ hybridization. The results showed that: on the 4th embryonic day (E4), Sema 3A mRNA was expressed around the neural tube and at the notocord. On E6 and E7, it was expressed in the ventral horn and around the central tube, appearing ventral dominance. On E8, the expression was mainly in the ventral horn, especially in the motor neurons. The results indicate that, the expression of Sema 3A in chick embryo shows a dynamic and ventral dominant tendency, and Sema 3A may play an important role in axon guidance in spinal cord development.