SerineArginineRich

Serineargininerich refers to a class of proteins or peptides that contain a high proportion of the amino acids serine and arginine, typically forming characteristic RS or SR dipeptide repeats. These motifs are most commonly found in the SR protein family, which plays a central role in pre‑mRNA splicing, RNA export, and signal transduction. The RS domains of SR proteins are intrinsically disordered, allowing them to interact with components of the spliceosome such as small nuclear ribonucleoproteins (snRNPs) and splicing factors. Phosphorylation of serine residues within the RS domain serves as a key regulatory switch, influencing subcellular localization, protein‑protein interactions, and the assembly of splicing complexes.

Serineargininerich motifs are also present in other RNA‑binding proteins, including heterogeneous nuclear ribonucleoproteins (hnRNPs) and various splicing regulators, suggesting a broader role in RNA metabolism. In addition to splicing, these proteins participate in transcriptional regulation, mRNA stability, and the cellular stress response. Comparative genomic analyses reveal that serineargininerich proteins are conserved across eukaryotes, underscoring their fundamental importance to gene expression. Due to their low complexity and rich serine‑arginine content, serineargininerich proteins are often implicated in disease when aberrantly phosphorylated or mutated, contributing to cancer, neurodegeneration, and viral replication. Studying serineargininerich domains remains a key area of molecular biology research, offering insights into the regulation of gene expression and the dysregulation associated with human diseases.