Rationalizing the effects of RNA modifications on protein interactions.

RNA modifications play a crucial role in regulating gene expression by altering RNA structure and modulating interactions with RNA-binding proteins (RBPs). In this study, we explore the impact of specific RNA chemical modifications-N-methyladenosine (m⁶A), A-to-I editing, and pseudouridine (Ψ)-on RNA secondary structure and protein-RNA interactions. Utilizing genome-wide data, including RNA secondary structure predictions and protein-RNA interaction datasets, we classify proteins into distinct categories based on their binding behaviors: modification specific and structure independent, or modification unspecific and structure dependent. For instance, m⁶A readers such as YTHDF2 exhibit modification-specific and structure-independent binding, consistently recognizing m⁶A regardless of structural changes. Conversely, proteins such as U2AF2 display modification-unspecific and structure-dependent behavior, altering their binding preferences in response to structural changes induced by different modifications. A-to-I editing, which causes significant structural changes, typically reduces protein interactions, while Ψ enhances RNA structural stability, albeit with variable effects on protein binding. To predict these interactions, we developed the RAPID 2.2 algorithm, which computes the effects of RNA modifications on protein-RNA binding propensities. This algorithm enables the prediction and analysis of RNA modifications' impact on protein interactions, offering new insights into RNA biology and engineering.