Table 1.

Effect of PER 2 and CRY 2 on the cell cycle of MCF-7 cells

	G1	S	G2/M
GFP	7414	15.57	10.29
pCS2	65.36	18.03	16.61
PER2	82.24	7.16	10.60
pCS2 + pcDNA3.1	62.61	17.49	19.90
PER2 + CRY2	89.19	0.58	10.22

Cell cycle analyses were conducted on parental, vector-transfected, PER 2 overexpressing MCF-7 cells, CRY 2 overexpressing MCF-7 cells, and cells over expressing both PER 2 and CRY 2. After three days of expression, propidium iodide(PI) staining and samples were analyzed by flow cytometry.