Multistranded organization of the lateral elements of the synaptonemal complex in the rat and mouse

Using electron microscopy, we have analyzed the structure of the lateral elements (LEs) of the synaptonemal complex (SC) in rat and mouse spermatocytes under different spreading conditions. Our observations indicate that in nearly 50% of the cells it is possible to detect more than one structural component of the LEs in the XY pair. When the same spreading conditions are used, the structure of the LEs is not the same in the autosomes and the XY pair. Moreover, the correlation between different spreading conditions and the detection of more than one sublateral element (subLE) was different in pachytene and diplotene spreads; it also varied depending on the species and meiotic stage. Our study supports the notion that the LEs of the SC are multistranded.