Sequence Analysis of V-conotoxins Reveals Repeat Domain at 3' Untranlated Region

• 1、School of Life Sciences and Technology,Tongji University, Shanghai 200092

Abstract：V-conotoxin is so far a rare superfamily, however, 16 out of 69 sequences identified in conus flavidus belongs to this superfamily, which highly attached our interest on this superfamily. By homologous analysis of the translated region, 5' and 3' untranslated region (UTR), and cysteine codon in the cysteine framework, we found V-conotoxins share high sequence homologue in different species. Although both V and O2 superfamilies bear both XV and VI/VII cysteine frameworks, the cysteine codon applied in the same position of the framework is different, which may indicate the convergent evolution of the same cysteine framework in these two superfamilies. To our interest, it was the first time that identification of repeat domain at the 3' UTR of V-contoxins. The (TATC)n repeat in the 3' UTR is conserved in different species, and so far is a unique feature for V superfamily.

Keywords： conotoxins, V superfamily, repeat, TATC, 3' UTR