Abstract
The fate of the synaptonemal complex and its elements after pachytene has been studied by serial sectioning of diplotene nuclei in mouse spermatocytes. The lateral elements of the synaptonemal complex separate from each other during diplotene, and they form single axes, 300 Å wide, surrounded by chromatin fibrils. The single axes are continuous and end on the nuclear membrane by two different ends: the basal knob and the simple end. The single axes do not cross-over each other, but they remain approached at the convergence regions. In these regions a modified piece of synaptonemal complex is found. This piece changes into a chromatin bridge during diplotene. It has been inferred that the convergence regions represent chiasmata and that the single axes do not represent axial structures of chromatids.
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Solari, A.J. The behaviour of chromosomal axes during diplotene in mouse spermatocytes. Chromosoma 31, 217–230 (1970). https://doi.org/10.1007/BF00285149
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DOI: https://doi.org/10.1007/BF00285149