SRProteine

SRProteine refers to a family of RNA-binding proteins characterized by arginine/serine-rich RS domains. They are involved in post-transcriptional RNA processing, particularly pre-mRNA splicing. Members are found across eukaryotes and are thought to act as splicing regulators that respond to cellular signals, stress, and development.

Structure: Most SRProteine contain one or more RNA recognition motifs (RRMs) that contact RNA, coupled with RS-rich regions that mediate protein–protein interactions and regulate activity through phosphorylation. The RS domain composition and motif arrangement vary among family members, conferring diverse interaction profiles.

Function: They recognize exonic splicing enhancers and promote assembly or activity of spliceosomal components at nearby sites. By modulating exon inclusion, alternative splicing patterns are adjusted in response to developmental cues or stress conditions. Subcellular localization can shift between nucleus and cytoplasm, influenced by phosphorylation status.

Regulation and evolution: Phosphorylation by SR protein kinases and CLK-like kinases modulates SRProteine localization and splicing activity. The gene family is broadly conserved, with lineage-specific expansions and extensive alternative splicing generating isoforms with distinct regulatory properties.

Clinical and research relevance: Altered SRProteine expression or function is associated with splicing-related disorders in model systems and, in principle, could contribute to human disease through splicing misregulation. SRProteine variants are used as experimental tools to study splicing control and as potential targets for therapeutic strategies that aim to influence exon choice.

Discovery and naming: The name derives from the RS (arginine–serine) dipeptide-rich domain that characterizes these proteins. The concept emerged during studies of spliceosome regulation in the late 20th century and has since guided investigations into RNA processing.