Isolation of a cDNA clone for a catalytic subunit of Torpedo marmorata acetylcholinesterase.

We have constructed a cDNA library from Torpedo marmorata electric organ poly(A+) RNA in the lambda phage expression vector lambda gt11. This library has been screened with polyclonal anti-acetylcholinesterase antibodies. One clone, lambda AChE1, produced a fusion protein which was recognized by the antibodies and which prevented the binding of native acetylcholinesterase in an enzymatic immune assay. These results indicate that lambda AChE1 contains a cDNA insert coding for a part of a catalytic subunit of Torpedo acetylcholinesterase. The 200-base-pair cDNA insert hybridized to three mRNAs (14.5, 10.5 and 5.5 kb) from Torpedo electric organs. These mRNAs were also detected in Torpedo electric lobes.