title: Probing murine male meiosis using unique DNA flanking the immunoglobulin heavy chain genes.
abstract: Murine male meiotic preparations were probed by in situ hybridization to localize 10.5 kb of unique DNA which flanks the C gamma 1 heavy chain immunoglobulin gene on the 5' side. The probe, inserted into the plasmid vector pBR 322, was labelled with I125 dCTP using nick translation. After exposing autoradiographs, made by standard techniques of in situ hybridization, for 40 days, a strong signal was obtained on one bivalent of size appropriate to pair 12. The signal was in the distal position on chromosome 12 and it could be traced from spermatogonial divisions through to mature sperm. The signal was strongest in some well-spread stages of prophase of first spermatocytes, weakest in early spermatids, then surprisingly strong in sperm heads. This variation is probably due to differences in the packaging of the target sequence at the various stages of meiosis.
mesh_terms: D000818:Animals; D002455:Cell Division; D002875:Chromosomes / Q000032:analysis*; D003001:Cloning, Molecular / Q000379:methods; D004274:DNA, Recombinant; D005796:Genes; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007399:Interphase; D008297:Male; D008540:Meiosis; D051379:Mice; D009693:Nucleic Acid Hybridization; D013091:Spermatogenesis; D013093:Spermatogonia / Q000166:cytology
chemical_list: D004274:DNA, Recombinant; D007143:Immunoglobulin Heavy Chains