Developmental stage-specific TF-miRNA co-regulatory network approach for studying craniofacial development. (A) Flowchart. (B-E) Candidate co-regulation types in FFLs. Arrows denote a directional regulation (either positive or negative role). The symbol ‘––|’ represents a repression role. DE, differentially expressed; DEG, differentially expressed gene; FDR, false discovery rate; FFL, feed-forward loop; miRNA, microRNA; PCC, Pearson's correlation coefficient; TF, transcriptional factor.