The RNA recognition motif (RRM), also known as RNA-binding domain (RBD) or ribonucleoprotein domain (RNP) is one of the most abundant protein domains in eukaryotes. Based on the comparison of more than 40 structures including 15 complexes (RRM–RNA or RRM–protein), we reviewed the structure–function relationships of this domain. We identified and classified the different structural elements of the RRM that are import-ant for binding a multitude of RNA sequences and proteins.
