电压门控钠离子通道scn1Laa参与斑马鱼脑神经发育和运动行为调节的研究

Voltage-gated sodium channel scn1Laa is involved in the development of zebrafish cranial nerves and the regulation of motor behavior

电压门控钠离子通道对于脊椎动物脑神经起始、传播动作电位具有重要作用。为了解斑马鱼电压门控钠离子通道基因scn1Laa在脑神经中的作用,通过CRISPR/Cas9基因编辑技术,首次构建了可稳定遗传的生长没有受明显影响的scn1Laa缺陷型(scn1Laa)斑马鱼家系。相比野生型,受精后5 d scn1Laa缺陷型斑马鱼兴奋抑制性神经元(氨基丁酸类神经元)表达相对增加,兴奋类神经元(谷氨酸能类神经元)和成熟神经元显著减少,脑部细胞增殖也显著减少。受精后5 d和90 d的scn1Laa缺陷型斑马鱼的运动较同时期野生型斑马鱼更为活跃,受精后90 d的scn1Laa缺陷型斑马鱼的运动具有明显的爆发性。以上结果表明,scn1Laa缺失导致兴奋类神经元(谷氨酸能类神经元)以及神经细胞增殖减少,影响脑周围神经放电,导致运动神经调节障碍,出现运动行为异常活跃,即电压门控钠离子通道基因scn1Laa参与斑马鱼脑神经发育和生长,间接参与运动行为调节。

Voltage-gated sodium channels(VGSC)play an important role in the initiation and propagation of action potentials in vertebrate cranial nerves.To investigate the role of zebrafish voltage-gated sodium channel member scn1 Laa in cranial nerves,the CRISPR/Cas9 approach was used to establish a stable hereditary scn1 Laa-deficient(scn1 Laa)zebrafish without significant effect on growth.Compared with wild-type siblings,there were more GABAergic neurons(inhibitory neurons)in scn1 Laa-deficient larvae at 5 dpf(5 days post-fertilization),while glutamatergic(excitatory neurons)and mature neurons were significantly reduced.Besides,cell proliferation in the brain was also reduced at 5 dpf.The movement of scn1 Laa-deficient zebrafish at 5 or 90 dpf was more active than that of wild-type siblings at the same time,and the burst movement of scn1 Laa-deficient zebrafish was observed at 90 dpf.These results showed that loss of scn1 laa made excitatory neurons(glutamatergic neurons)decrease and reduced cell proliferation of cranial nerve,which affected the discharge of peripheral nerve,causing motor nerve dysfunction and abnormal motor behavior.Above all,the voltage-gated sodium channel scn1 Laa participates in the development and functional maintenance of the zebrafish cranial nerve and indirectly participates in the regulating behavior with limited influence on body growth.At the same time,this research also lays the foundation for further exploration of voltage-gated sodium channels in the cranial nerves.