Are different messenger RNA species translated in distinct, limited domains within a cell? For the particular case of the giant R2 neuron from Aplysia californica an answer to this question is possible for the more abundantly synthesized proteins. After brief labeling with 35S-methionine, the R2 neuron soma was frozen and divided into two or three parts. The newly synthesized proteins were analyzed following two-dimensional polyacrylamide gel electrophoresis. No evidence for limited domains of synthesis for 26 abundantly synthesized polypeptides in the R2 neuron was found.