Soong Tuck Wah, Venkatesh Byrappa
Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597.
Trends Genet. 2006 Nov;22(11):621-6. doi: 10.1016/j.tig.2006.08.010. Epub 2006 Sep 7.
Tetrodotoxin (TTX), first isolated from pufferfish (tetraodontids), is a highly potent neurotoxin that selectively binds to voltage-gated sodium channels (Na(v)) in muscle and nerve tissues causing paralysis and death. Saxitoxin (STX) is a TTX-related neurotoxin produced by dinoflagellates. Recent investigations have implicated diverse substitutions in the P-loop regions of skeletal muscle and neuronal Na(v) channels in the convergent evolution of neurotoxin resistance in pufferfish, garter snakes and softshell clams, which has enabled them to feed on TTX- and STX-bearing organisms.
河豚毒素（TTX）最初是从河豚（鲀科鱼类）中分离出来的，是一种剧毒神经毒素，它选择性地与肌肉和神经组织中的电压门控钠通道（Na(v)）结合，导致麻痹和死亡。石房蛤毒素（STX）是一种由双鞭毛藻产生的与TTX相关的神经毒素。最近的研究表明，河豚、束带蛇和软壳蛤在对神经毒素产生抗性的趋同进化过程中，骨骼肌和神经元Na(v)通道的P环区域存在多种替代情况，这使它们能够以含有TTX和STX的生物为食。
