Related Experiment Video
Updated: Jun 28, 2026

Development and Application of Rapamycin-regulated Tyrosine Phosphatases
Published on: September 6, 2024
HSP90 beta regulates rapsyn turnover and subsequent AChR cluster formation and maintenance
Shiwen Luo1, Bin Zhang, Xian-Ping Dong
1Program of Developmental Neurobiology, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912, USA.
Abstract:
Rapsyn, an acetylcholine receptor (AChR)-interacting protein, is essential for synapse formation at the neuromuscular junction (NMJ). Like many synaptic proteins, rapsyn turns over rapidly at synapses. However, little is known about molecular mechanisms that govern rapsyn stability. Using a differential mass-spectrometry approach, we identified heat-shock protein 90beta (HSP90beta) as a component in surface AChR clusters. The HSP90beta-AChR interaction required rapsyn and was stimulated by agrin. Inhibition of HSP90beta activity or expression, or disruption of its interaction with rapsyn attenuated agrin-induced formation of AChR clusters in vitro and impaired the development and maintenance of the NMJ in vivo. Finally, we showed that HSP90beta was necessary for rapsyn stabilization and regulated its proteasome-dependent degradation. Together, these results indicate a role of HSP90beta in NMJ development by regulating rapsyn turnover and subsequent AChR cluster formation and maintenance.
Related Concept Videos
Regulation of Nuclear Protein Sorting
Chromatin Structure Regulates pre-mRNA Processing
The chromatin structure, especially...
Directing Proteins to the Rough Endoplasmic Reticulum
PI3K/mTOR/AKT Signaling Pathway
Regulation of the Unfolded Protein Response
Export of Misfolded Proteins out of the ER

