Demonstration of replication patterns in the last premeiotic S-phase of male Chinese hamsters after BrdU pulse labeling.
Chromosome replication in the last premeiotic S-phase of male mammals has been previously studied by [3H]thymidine autoradiography and by a 5-bromodeoxyuridine (BrdU)/Giemsa technique. We used a recently developed BrdU-antibody technique (BAT) in this study. The following conclusions were drawn: (1) The replication patterns observed are similar to that of somatic cells. (2) The heterochromatin starts replication in early S-phase. (3) The euchromatic part of the X chromosome of the male Chinese hamster replicates together with the autosomes and therefore behaves isocyclicly and not allocyclicly as hitherto assumed. Hence, genetic inactivity of the X chromosome may be brought about by a mechanism different from that in somatic cells.
Latos-Bielenska
A
A
Abteilung Klinische Genetik, Universität Ulm, Federal Republic of Germany.
Vogel
W
W
D000818:Animals; D001973:Bromodeoxyuridine; D002875:Chromosomes / Q000502:physiology*; D006224:Cricetinae; D003412:Cricetulus; D007150:Immunohistochemistry; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D016196:S Phase / Q000235:genetics*; D013737:Testis / Q000166:cytology; D014960:X Chromosome
D001973:Bromodeoxyuridine