34 DNA Replication in Physarum
نویسنده
چکیده
The natural synchrony of the nuclear cycle within the plasmodium of the myxomycete Physarum polycephalum provides an opportunity to study, without the need for any cell treatment, the complex and transient patterns of replication intermediates generated during chromosomal replication. In this review, we focus on the parameters of replication kinetics from the synthesis of Okazaki fragments to the chromosome-sized progeny molecules and summarize data suggesting that their appearance at some specific loci is precisely programmed and intimately linked to the transcriptional activity of the cell.
منابع مشابه
Regulation of Dna Replication in the Nuclei of the Slime Mold Physarum Polycephalum
Nuclei in G2 phase of the slime mold Physarum polycephalum, when transplanted, by plasmodial coalescence, into an S-phase plasmodium, failed to start another round of DNA synthesis. In the reciprocal combination, S-phase nuclei in a G2-phase host continued DNA synthesis for several hours without appreciable decrease in rate. It is suggested that the beginning of DNA replication is determined by...
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The direction of replication of DNA within replicons of Physarum polycephalum was studied by pulse-labelling with 5-bromouracil-deoxyriboside (BrdUrd) and 3H-adenosine deoxyriboside (dAdo), followed by ultraviolet- (UV) -photolysis and analysis of molecular weights of single strand DNA fragments on alkaline sucrose gradients. Newly made DNA within replicons at all stages of completion is split ...
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