Fig. 2. Schematic for production of chimeric cDNAs. (A ) Wild-type receptor cDNAs (GABA ρ1, dark gray; glycine α1, striped) in plasmid (pRK7, light gray). Note restriction enzyme recognition sites for Nde I and BssH II. 5′ and 3′ as defined in figure 1. (B ) Fragments formed after digest with Nde I and BssH II. (C ) Exchange of smaller fragments and ligation to generate two chimeric cDNAs.