Figure 9. Load-Release-Transfer model for capsid traffic toward late-pachytene/diplotene nuclei.

Cartoon of capsids and microtubules as germ cells progress into late pachytene/diplotene. Capsids that had accumulated on stable microtubules (black) in the core (top) are released as these microtubules depolymerize. The released capsids transfer to surrounding labile, or dynamic, microtubules (red) and traffic into germ cells. In an alternative model, capsids could remain on the original microtubule as it becomes destabilized. Traffic could involve microtubule dynamics, or microtubule motor proteins.