Related Experiment Video
Updated: May 5, 2026
11:09
Characterizing the Composition of Molecular Motors on Moving Axonal Cargo Using "Cargo Mapping" Analysis
Published on: October 30, 2014
9.2K
Structural basis of myosin V Rab GTPase-dependent cargo recognition
Olena Pylypenko1, Wikayatou Attanda, Charles Gauquelin
1Structural Motility, Institut Curie, 75248 Paris Cedex 05, France.
Summary
Molecular motors like myosin V use specific cargo recognition for cellular functions. Structural insights reveal conserved Rab11 binding and evolved melanophilin interaction sites in myosin V isoforms.
Area of Science:
- Cell Biology
- Structural Biology
- Molecular Evolution
Background:
- Molecular motors are essential for intracellular transport, linking cargo to cytoskeleton tracks.
- Isoform-specific functions arise from conserved and novel cargo recognition sites, but evolutionary mechanisms remain unclear.
Purpose of the Study:
- To investigate the structural basis of cargo recognition by myosin V motor domains.
- To understand how evolutionary divergence in myosin V isoforms generates specialized cellular functions.
Main Methods:
- X-ray crystallography to determine the structures of myosin Va and myosin Vb globular tail domains (GTDs).
- Structural analysis of GTD interactions with Rab11 and melanophilin.
Main Results:
- Crystal structures reveal how myosin V motors link to recycling endosomes via Rab11.
- Myosin Va specifically recognizes melanophilin, an adaptor for melanosome cargo, via an evolved GTD interaction site.
- The Rab11-binding site is evolutionarily conserved across myosin V isoforms.
Conclusions:
- Myosin V cargo specificity is achieved through a combination of conserved and divergent interaction sites within the GTD.
- Structural plasticity of the GTD or its binding partners is crucial for selective motor recruitment.
- Understanding these mechanisms provides insight into the evolution of specialized cellular functions.
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