1681-Cargo Crosslinking and AP-1 Lattice Formation

Recent scientific research reveals that intracellular transport vesicles are actively shaped by their contents rather than relying solely on coat-driven mechanisms. By employing cryogenic-electron microscopy, investigators discovered that specific proteins containing tandem sorting motifs can directly bridge adjacent AP-1 adaptor complexes to nucleate lattice assembly. This crosslinking occurs through a newly identified μ1-σ1 inter-complex interface that transforms weak individual interactions into a stable architectural framework. Cellular assays and animal models further demonstrate that disrupting this specific interface impairs crucial intracellular cargo trafficking and leads to severe neurodevelopmental defects in zebrafish. Ultimately, these findings establish that cargo molecules play an active structural role in building their own transport machinery, fundamentally expanding our understanding of vesicle biogenesis.

References:

• Deng H, Jia G, Yang Q, et al. Cargo crosslinking nucleates AP-1 lattice formation[J]. Cell, 2026.