A transgenic construct containing the entire open reading frame of the Yellow Fluorescent Protein gene fused in-frame with the mitochondrial targeting sequence of the mouse cytochrome c oxidase, subunit VIIIa, gene under the direction of regulatory elements derived from the rat enolase 2, gamma gene, Eno2, was injected into fertilized C57BL/6J donor mouse eggs. Founder line Z was established. YFP is specifically localized to the mitochondria by a mouse cytochrome c oxidase, subunit VIIIa, gene targeting signal fused to the N-terminus. Fluorescence is detected in many neuronal populations. (J:122259)