Abstract
Genome integrity is maintained by coupling DNA damage repair to the cell cycle arrest during the repair. The fact that plants do not possess orthologs of some of the key factors that are important for the cell-cycle arrest in animal cells, implies that they probably have different mechanisms to cope with DNA damage.
In plant cells, A- and B-type cyclin-dependent kinases (CDKA and CDKB) are assumed to mainly control cell cycle progression. CDKAs are expressed throughout the cell cycle, while CDKBs are plant-specific CDKs and expressed specifically from the late S- to the M-phase. Recently, we found that the expression of CDKB2 is specifically suppressed in response to DNA damage. Together with the results of cultured cells, we hypothesize that this quantitative regulation of CDKB2 is required for inhibiting progression into mitosis in response to DNA damage.
