Details

Autor(en) / Beteiligte

• Joensuu, Merja
• Padmanabhan, Pranesh
• Durisic, Nela
• Bademosi, Adekunle T D
• Cooper-Williams, Elizabeth
• Morrow, Isabel C
• Harper, Callista B
• Jung, WooRam
• Parton, Robert G
• Goodhill, Geoffrey J
• Papadopulos, Andreas
• Meunier, Frédéric A

Titel

Subdiffractional tracking of internalized molecules reveals heterogeneous motion states of synaptic vesicles

Ist Teil von

• The Journal of cell biology, 2016-10, Vol.215 (2), p.277-292

Ort / Verlag

United States: Rockefeller University Press

Erscheinungsjahr

2016

Quelle

MEDLINE

Beschreibungen/Notizen

• Our understanding of endocytic pathway dynamics is severely restricted by the diffraction limit of light microscopy. To address this, we implemented a novel technique based on the subdiffractional tracking of internalized molecules (sdTIM). This allowed us to image anti-green fluorescent protein Atto647N-tagged nanobodies trapped in synaptic vesicles (SVs) from live hippocampal nerve terminals expressing vesicle-associated membrane protein 2 (VAMP2)-pHluorin with 36-nm localization precision. Our results showed that, once internalized, VAMP2-pHluorin/Atto647N-tagged nanobodies exhibited a markedly lower mobility than on the plasma membrane, an effect that was reversed upon restimulation in presynapses but not in neighboring axons. Using Bayesian model selection applied to hidden Markov modeling, we found that SVs oscillated between diffusive states or a combination of diffusive and transport states with opposite directionality. Importantly, SVs exhibiting diffusive motion were relatively less likely to switch to the transport motion. These results highlight the potential of the sdTIM technique to provide new insights into the dynamics of endocytic pathways in a wide variety of cellular settings.