Premium
Early replicating DNA involved in the G2 to M transition in Allium cepa L meristematic cells
Author(s) -
Concha Miguel L.,
Sans Jorge
Publication year - 1995
Publication title -
biology of the cell
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.543
H-Index - 85
eISSN - 1768-322X
pISSN - 0248-4900
DOI - 10.1016/0248-4900(96)89937-0
Subject(s) - mitosis , biology , interphase , meristem , cell cycle , microbiology and biotechnology , dna synthesis , cell division , dna , cell , genetics , gene
Summary— The involvement of genome portions replicating at different times of the S phase in the control of cell cycle events was analysed in Allium cepa L meristematic cells. 5‐Azacytidine (5‐azaC) was incorporated into discrete replicating DNA portions in synchronous cells. Cells treated with 5‐azaC during the late S phase went through normal cell cycles while cells treated with 5‐azaC during the early S phase were able to go through the immediately succeeding mitosis, as well as to begin the subsequent S phase. However, they were unable to enter a second mitosis. Thus, sequences replicating in the early S phase appear to code for a mitotic inhibitor which represses the emergence of a positive mitotic signal. This inhibition took place in the first half of the interphase ( ie during G1) and resulted in a cell cycle blockage in G2.