Before revision:  While many endogenous homeostatic motifs have been studied in living cells, synthetic homeostatic circuits have received far less attention. The tight regulation of the abundance of cellular products and intermediates in the noisy environment of the cell is now recognised as a critical requirement for several biotechnology and therapeutic applications .
After revision:  While many endogenous homeostatic motifs have been studied in living cells, some other motifs may remain under-explored or even undiscovered. At the same time, known regulatory motifs have been mostly analyzed at the deterministic level, and the effect of noise on their regulatory function has received low attention .