Backup machinery of yeast transcriptional regulatory network

Abstract

Several studies have suggested the existence of backup machinery of transcriptional regulatory networks (TRNs). Here, we have quantified the backup machinery of yeast gene's TRNs under five different conditions in terms of alternate paths and have revealed that a statistically significant (p<0.0001) stronger backup is maintained for endogenous processes (ENPs) than exogenous processes (EXPs). A number of biologically important genes (SUC2, MF(ALPHA)2, CLN2 etc) are observed that maintain a higher backup. Hub and random transcription factor (TF) knockouts in TRNs have showed ENPs are more robust to deletion than EXPs. While higher average connectivity of TFs in EXPs than ENPs can't explain the higher robustness in ENPs, we have found that the later have a densely interconnectedness explaining their specialized architecture that may have evolved due to evolutionary pressure. Some non-hub TFs identified here are more likely to be essential, and if not essential, have a larger impact on fitness.