Nkx2-5 is a homeodomain-containing transcription factor that is involved in regulating the expression of genes that control heart formation, cardiac morphogenesis, and differentiation of cardiac progenitor cells. The Nkx2-5 luciferase reporter vector is designed to study the transcriptional activity of Nkx2-5. The vector contains an Nkx2-5 DNA consensus binding site and TA minimal promoter upstream of a firefly luciferase reporter gene, which can specifically report Nkx2-5 activity while maintaining a low basal level of transcription.