Date Published: November 24, 2009
Publisher: Public Library of Science
Author(s): Heidi M. Blank, Shefali Gajjar, Andrey Belyanin, Michael Polymenis, Paul Cobine. http://doi.org/10.1371/journal.pone.0008018
Abstract: Sulfur metabolism is required for initiation of cell division, but whether or not it can actively promote cell division remains unknown.
Partial Text: Growth is rate limiting for cell division. It has been known for some time that growth and metabolism are required for cell division to take place . However, whether metabolism can actively promote cell division remains largely unaddressed due to the previous use of loss-of-function metabolic mutants when studying the coordination of growth and division. The S. cerevisiae nuclear gene ABF2+ encodes a highly conserved mitochondrial DNA maintenance protein, called TFAM in animals, which binds to and bends mitochondrial DNA (mtDNA) , . Moderate over-expression of Abf2p, from a low copy number plasmid or from two extra copies integrated in the genome, increases the amount of mtDNA by 50–150% . We have previously shown that moderate over-expression of Abf2p causes cells to increase in size faster and accelerate initiation of DNA replication in the nucleus . Furthermore, cells with more mtDNA proliferate faster than their wild type counterparts when cultured under carbon limiting conditions . These unique properties of cells over-expressing Abf2p represent an experimental system that allows for the eventual dissection of how metabolism can promote cell division.