Zinc Finger Protein 703 (ZNF703)

The zebrafish nlz1/znf703 and nlz2/znf503 genes are closely related to the Drosophila noc and elbow genes, the C. elegans tlp-1 gene and several mammalian genes. Together these genes make up a subclass (the NET family) that is related to the Sp family of zinc finger transcription factors. Specifically, NET family proteins share three sequence motifs (a 'buttonhead box', an 'Sp motif' and a C₂H₂ zinc finger) with Sp family proteins. While Sp family transcription factors (Sp1–Sp8) are sequence-specific transcription factors acting as activators or repressors depending on the cellular context, it is unclear if NET proteins play a similar role. For instance, Sp proteins contain three C₂H₂ zinc fingers that bind DNA, but NET proteins contain only one zinc finger and this may not be sufficient to bind DNA.