Fig. 1

Schematic cloning representation of α- and β-subunits of Sp-CTx. Forward and reverse primers are indicated by white and black arrows, respectively. The sequence of primers is shown in Table 1. Amino-acid positions are relative to the primary structures of cDNAs from Synanceia. The positions of the arrows indicate the approximate size of the putative fragment. Initiation codon (M) and stop codon (STOP). a: Union of putative fragments in α-subunit was obtained by PCRs (αT-f and Catαf-r, Catα-f and Catα-r, Deg2-f and Deg-r, Degr-f and Synα-r). b: Union of putative fragments in β-subunit (βT-f and CDβ-r were isolated from the cDNA library and CDβr-f and Synβ-r obtained by PCR)