Spatio-temporal over-representation of transcription factors in embryonic development. This figure uses the slim representation of the anatomical ontology from Tomancak et al.  with the same color codes. The number of TFs expressed at the given spatio-temporal coordinate is provided in brackets, and the decimal number indicates the Z score for the over-representation of TFs in comparison to non-TFs. Statistically significant enrichment of TFs versus non-TFs (Z > 3) is highlighted in red.