Mathematical modeling has played a pivotal role in advancing the understanding of gene expression regulation, operating at both the molecular and cellular levels. In this dissertation, stochastic models and simulations will be employed to explore the impact of various forms of cellular compartmentalization, such as the formation of functionally distinct RNA condensates or the establishment of nuclear territories in syncytia, on the robust spatiotemporal control of gene expression within cells. The highlighted model system, multinucleated filamentous fungi, serves as a prime example of global coordination and compartmentalization within expansive cytoplasmic environments. To complement these modeling efforts, image analysis on live cell data will be employed to quantify and localize RNAs, providing a means by which key model parameters can be inferred and the model's validity can be assessed within physiologically relevant contexts.