AMPA receptors are ion channel tetramers that mediate fast excitatory neurotransmission in vertebrate brains. AMPAR functional properties as well as receptor biogenesis in the endoplasmic reticulum (ER) are shaped by RNA processing events, including adenosine-to-inosine RNA editing and alternative splicing. Recoded sites line interfaces of subunit polypeptides, and are therefore ideally positioned to modulate receptor assembly. Moreover, the genomic arrangement of the R/G editing site within the splice donor of the alternative flip/flop exons may facilitate a cross-talk between these genetic elements. Regulated mRNA recoding in response to neuronal activity would have the scope to sculpt AMPAR tetramers and in turn shape the response properties of a neuron.