5种南海产芋螺粗毒组分对α3β2和α4β2乙酰胆碱受体阻断活性研究

Blocking activity study of crude venom fractions of five cone snails from South China Sea againstα3β2 andα4β2 nAChRs

目的为南海产丰富的芋螺生物资源的深入挖掘和开发利用,为从毒液中发现和寻找新型活性强、选择性好的阻断α4β2 nAChR的芋螺毒素奠定基础。方法通过对5种南海常见芋螺(豹芋螺、黑芋螺、玉女芋螺、信号芋螺、和帝王芋螺)的毒液进行提取、分段,并采用双电极电压膜片钳技术测定了5种毒液各个组分对α4β2 nAChR和α3β2 nAChR的阻断活性。结果豹芋螺、黑芋螺、信号芋螺和帝王芋螺这4种芋螺毒液的部分组分表现出较好的α4β2 nAChR阻断活性,同时也对α3β2 nAChR具有一定的阻断作用。豹芋螺大部分组分和黑芋螺毒液Mar-2组分对α4β2 nAChR有明显的阻断作用,阻断率分别高达40%以上和73.6%,且这些组分未对α3β2 nAChR表现出阻断作用或作用很弱,即对α4β2 nAChR有良好活性且相比于α3β2 nAChR对α4β2 nAChR有较好的选择性。结论本研究结果为后续对豹芋螺粗毒组分进行活性跟踪的分离纯化,为获得豹芋螺来源的新型芋螺毒素并阐明其结构和功能提供理论依据,为后续寻找选择性阻断α4β2 nAChR的新型芋螺毒素指明了研究方向,为深入开发利用南海产芋螺生物资源奠定了坚实基础。

Objective To deeply develop and utilize the rich biological resources of cone snails in the South China Sea,and lay the foundation for the discovery of new conotoxins that blockα4β2 nAChR with potent activity and high selectivity from cone snail venom.Methods The crude venom of five common species of cone snails(Conus leopardus,Conus marmoreus,Conus virgo,Conus litteratus and Conus imperialis)from South China Sea were extracted and fractionated.The blocking activities of the five venom fractions onα4β2 andα3β2 nAChRs were evaluated by the two-electrode voltage patch clamp technique.Results Partial fractions of four cone snail venom from Conus leopardus,Conus marmoreus,Conus litteratus and Conus imperialis exhibited goodα4β2 nAChR blocking activity,and also showed a certain blocking effect onα3β2 nAChR.Significant blocking activities onα4β2 nAChR were demonstrated for most fractions of Conus leopardus and the fraction Mar-2 of Conus marmoreus,with the blocking rate were as high as more than 40%and 73.6%,respectively.These fractions presented a weak or barely no blocking effect onα3β2 nAChR,which meant they showed good activity and high selectivity onα4β2 nAChR rather than onα3β2 nAChR.Conclusion The results of this study had provided a theoretical basis for the follow-up bioactive-guided purification of the venom fraction of Conus leopardus to obtain Conus leopardus-derived new conotoxins for their structure and function study,and pointed out the research direction for discovering new conotoxins which potently and selectively blockα4β2 nAChR from cone snail venom,and laid a solid foundation for further development and utilization of the biological resources of cone snails derived from the South China Sea.