The construct consisting of mAmetrine-2A-Neuropilin-1 was inserted in the ATG start codon within the Rosa26 locus downstream of the lox-stop-lox cassette. Ametrine is a long stokes shift (excitation at 406 nanometers and emission at 526 nanometers) yellow fluorescent protein derived from Aequorea victoria. The linearized targeting construct was electroporated into JM8A3.N1 embryonic stem. (J:299786)