Retrotransposon Gag-like protein 8B (RTL8B)

Retrotransposon Gag-like protein 8B (RTL8B) is a small, eutherian-specific protein encoded by the RTL8B gene, which is clustered on the X chromosome alongside RTL8A and RTL8C. These proteins are derived from endogenous retroviral sequences and share high homology. RTL8B is expressed in both the nucleus and cytoplasm of neurons, with evidence for nucleolar localization and involvement in subnuclear protein quality control condensates, particularly by interacting with the ubiquitin receptor UBQLN2. In mouse models, deletion of Rtl8a and Rtl8b leads to neuropsychiatric-like behaviors, late-onset obesity, and reduced social response, recapitulating symptoms seen in human Prader–Willi syndrome and suggesting a role in neural gene regulation or maintenance. While its exact molecular function remains under investigation, RTL8B is implicated in the regulation of UBQLN2 nuclear translocation during cellular stress and is associated with certain neurodevelopmental and neurodegenerative diseases through expression or processing changes, but it is not established as a direct therapeutic target and has no current drug interactions.

Other names

CXX1CFAM127CMAR8BSIRH4CXX1cSushi-Ichi retrotransposon homolog 1mammalian retrotransposon derived protein 8Bmammalian retrotransposon-derived 2protein FAM127C