ISSN:
1365-2958
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
,
Medicine
Notes:
We describe the use of time-lapse fluorescence microscopy to visualize the movement of the DNA replication origin and terminus regions on the Bacillus subtilis chromosome during the course of the cell cycle. The origin and terminus regions were tagged with a cassette of tandem lac operator repeats and visualized through the use of a fusion of the green fluorescent protein to the LacI repressor. We have discovered that origin regions abruptly move apart towards the cell poles during a brief interval of the cell cycle. This movement was also seen in the absence of cell wall growth and in the absence of the product of the parB homologue spo0J. The origin regions moved apart an average distance of 1.4 μm in an 11 min period of abrupt movement, representing an average velocity of 0.17 μm min−1. and reaching a maximum velocity of greater than 0.27 μm min−1. The terminus region also exhibited a striking pattern of movement but not as far or a rapid as the origin region. These results provide evidence for a mitotic-like motor that is responsible for segregation of the origin regions of the chromosomes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-2958.1998.00808.x
