Figure 6.

Two-component reciprocal repression. A reciprocal repression subnetwork consists of pair of genes (X₁ and X₂) in which each gene's product blocks transcription of the other gene, either as a monomer (X_i + P_j ⇌ X_jP_j for i ≠ j) or a dimer (P_i + P_I ⇌ P_i P_i and X_i + P_j P_j ⇌ X_i P_j P_j for i ≠ j). Basal protein production (X_i → X_i + P_i) and protein degradation (P_i → ∅) are also included in specification of the subnetwork.