*4.1. Filtering of e7.5 and e9.5 Placenta RNA-seq Data*

We obtained previously analyzed and published e7.5 and e9.5 placenta RNA-seq data from the Gene Expression Omnibus (GSE65808) [13]. TFs were identified from the Animal Transcription Factor Database(v2.0) [101]. TFs were considered highly expressed and retained for analysis if they had an FPKM ≥ 10 at e9.5 and were significantly upregulated compared to e7.5 (fold ≥ 2 and *q*-value ≤ 0.05).
