LOCALIZATION OF RECA-LIKE PROTEINS IN SPREAD NUCLEI OF MOUSE SPERMATOCYTES AT MEIOTIC PROPHASE-I

Earlier, polyclonal antibodies to Escherichia coli RecA protein were u sed to identify immunologically related proteins in meiotic spermatocy tes of different eukaryotes. At least one such protein proved to be a component of the synaptonemal complex (SC) [1]. Subsequent experiments on localization of RecA-like antigens in SCs of spermatocytes were pe rformed by indirect immunocytochemical methods and electron microscopy , which showed that RecA-like protein(s) at early leptotene are largel y associated with chromatin. During SC formation (at leptotene and zyg otene), they are found in both lateral elements and the central space of SC. In some cases, RecA-like proteins are associated with SC substr uctures that resemble recombination nodules. When spermatocytes enter late diplotene, RecA-like proteins cease to be detected in SC structur es.