Emergence of bimodal first passage time distributions from transcription translation coupling

Transcription and translation are fundamentally stochastic processes that drive significant variability in mRNA and protein levels within living cells. In certain cellular environments, these processes occur simultaneously, motivating the Transcription-Translation Coupled (TTC) model. We present a simple model of stochastic gene regulation incorporating TTC that yields bimodality in protein synthesis dynamics. By casting the estimation of protein synthesis times as a first-passage time (FPT) problem, we demonstrate that TTC generates robust bimodal FPT statistics with possible implications for bacterial survival strategies.