Beijing Institute of Biotechnology, China.
Acta Biochim Biophys Sin (Shanghai). 2010 Sep;42(9):656-61. doi: 10.1093/abbs/gmq066. Epub 2010 Aug 9.
In our efforts for cloning novel I(2)-superfamily conotoxins using the signal peptide sequence, we identified a novel conotoxin Lt12.4 from Conus litteratus. This gene has a framework XII (-C-C-C-C-CC-C-C-), which is distinct from the cysteine pattern I(2)-superfamily conotoxin (-C-C-CC-CC-C-C-). Subsequently, we found the signal peptide sequence of Lt12.4 by 5'-RACE. Using this new sequence, we identified another five novel conotoxins with this cysteine pattern from four Conus species (Conus eburneus, Conus imperialis, Conus marmoreus, and C. litteratus). These novel conotoxins have the same cysteine pattern as the reported Gla-TxX and Gla-MII, and may contain Gla residues. Furthermore, they have the highly conserved signal peptide and hypervariable mature peptide sequences, and widely exist in Conus species. Therefore, it could be defined as a new superfamily of E-conotoxins.
在使用信号肽序列克隆新型 I(2)-超家族芋螺毒素的努力中，我们从织纹芋螺（Conus litteratus）中鉴定出一种新型的芋螺毒素 Lt12.4。该基因具有框架 XII（-C-C-C-C-CC-C-C-），与半胱氨酸模式 I(2)-超家族芋螺毒素（-C-C-CC-CC-C-C-）不同。随后，我们通过 5'-RACE 找到了 Lt12.4 的信号肽序列。利用这条新序列，我们从四个芋螺物种（斑豹芋螺、帝王芋螺、织纹芋螺和织纹芋螺）中鉴定出另外五个具有这种半胱氨酸模式的新型芋螺毒素。这些新型芋螺毒素与报道的 Gla-TxX 和 Gla-MII 具有相同的半胱氨酸模式，可能含有 Gla 残基。此外，它们具有高度保守的信号肽和超变成熟肽序列，广泛存在于芋螺属物种中。因此，它可以被定义为一个新的 E-芋螺毒素超家族。
