Table 1.

Expression levels of cyclins, cyclin-dependent kinases (CDKs) and phosphorylation status of retinoblastoma protein (RB) in mESCs and hESCs during cell cycle progression.

	mESCs	hESCs
Cyclin expression levels
Cyclin A/E	High, non-oscillatory	High, oscillatory
Cyclin B	High, oscillatory	High, oscillatory
Cyclin D	Low, oscillatory	Intermediate, oscillatory
CDKs expression levels
CDK1	High, oscillatory	High, oscillatory
CDK2	High, non-oscillatory	High, oscillatory
CDK4	Low, oscillatory	Medium, oscillatory
CDK6	Medium, oscillatory	Low, oscillatory
RB phosphorylation
RB	Hyper-phosphorylated	Hypo-/Hyper-phosphorylated