The Ro60-Ro52 Complex as a New Player in Intracellular Humoral Immunity

Abstract

The Ro/SSA antigen complex contains Ro60 (TROVE2), Ro52 (TRIM21), and Y-RNA molecules that have recently emerged as the cornerstone of intracellular immunity and are thought to be the main target of autoantibodies in systemic autoimmune diseases. For decades, the precise nature of the Ro60-Ro52 interaction has been a matter of controversy. We have recently shown that the Ro60-Ro52 complex is transient and dynamic under physiological conditions. These results not only improve our understanding of Ro antigen biology but also highlight the possibility of targeted modulation approaches for autoimmune diseases. This communication explores a fascinating and largely unexplored aspect of intracellular humoral immunity through the Ro60-Ro52 complex, aiming to deepen our understanding of this pivotal interaction and its implications for cellular processes and disease.

Keywords

intracellular humoral immunity / Ro60-Ro52 complex / Ro52/TRIM21 / Ro60/TROVE2 / proteasomal degradation / RNA quality control / ubiquitin E3 ligase / systemic autoimmune diseases

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