The EAAT4 start codon, in exon 2, was mutated to TTG, and the EGFP cDNA (Clontech) was inserted downstream, after the end of the A-box, within the same exon. Lines 41 and 61 was generated with line 41 exhibiting higher expression levels. Line #a represents the unspecified line used at the Crick Institute. (J:270969)