Selective tracking of template DNA strands after induction of mitosis with unreplicated genomes (MUGs) in Drosophila S2 cells

• Type: Article in International Scientific Journal
• Date: 2013

Authors

Drpic, D (Author) Other; Barisic, M (Author) Other; Pinheiro, D (Author) Other; Helder Maiato (Author) FMUP

Journal

Title: Chromosome Research

Vol. 21

Pages: 329-337

ISSN: 0967-3849

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 3 Citations

Other information

Authenticus ID: P-005-0X1

DOI: 10.1007/s10577-013-9354-z

Abstract (EN): According to the "immortal" DNA strand hypothesis (Cairns Nature 255:197-200, 1975), stem cells would keep their template strands in order to prevent the accumulation of mutations, which could occur during DNA replication. Despite the growing number of studies that attempt to test this hypothesis, the conclusions remain highly controversial. In the base of this controversy lie the current limitations of available methodology to selectively and faithfully track the fate of template DNA strands throughout and upon cell division. Here, we developed a method that allows the unequivocal tracking of single chromatids containing template DNA strands in Drosophila S2 cells in culture. This method consists in the induction of mitosis with unreplicated genomes (MUGs) in which cells are allowed to enter mitosis without prior DNA replication. This is achieved by RNAi-mediated knockdown of Double parked, a conserved protein required for the initiation of DNA replication and post-replication checkpoint response. The advantages of this system when compared with MUGs generated in mammalian cells is the preservation of chromatid morphology, the ease of loss-of-function studies and the possibility of in vivo applications. Altogether, this approach allows for the readily visualization and tracking of template DNA strands by simply monitoring cells stably expressing GFP-fusions with either Histone H2B or the centromeric Histone variant CID/CENP-A by time-lapse fluorescence microscopy. This might be useful for the dissection of the molecular mechanism behind asymmetric DNA strand segregation.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9