Recombination nodules (RNs) are multicomponent proteinaceous ellipsoids found in association with the synaptonemal complex (SC) during prophase I of meiosis.
Location:
Electron micrographs of the synaptonemal complex disclose that many particles called early recombination nodules are found between the homologous as the complex assembles.
These nodules are similar in size and number to the recombination complexes that are seen in leptotene and that largely disappear by the end of zygotene.
It is expected, but unproven, that they constitute all recombination sites or possibly just the sites of non-crossover events.
A small number of nodules mature into much larger late recombination nodules that lie atop the synaptonemal complex and correspond to sites of crossover formation.