Adenoviruses contain the E3 region of genes which have immunomodulatory functions. One such protein is RID, the Receptor of Internalisation and Degradation which can target a small subset of structurally diverse membrane receptors for down~ modulation. This study focuses on the interactions(between RID molecules and two such target receptors, the Fas and the epidermal growth factor receptor (EGFR). Removal of Fas from the surface of Adenovirus infected cells protects them from adaptive immune responses. This study primarily focuses on the regions within the Fas receptor that are important for RID mediated down-modulation. The transmembrane and cytoplasmic tail are critical for the regulation, mutant Fas receptors have been generated and we have specifically identified the regions and amino acids involved with binding to RID, in the context of Adenovirus species 2 (Ad2) infection. Similarly, the EGFR is targeted by RID, this thesis studies the ability of Ad2 to target EGFR for down-regulation and destruction.