(center map)
(1) DP2*:E2F4@nucleus+p107*@nucleus -> DP2*:E2F4:p107*@nucleus
(2) DP2*:E2F4:p107*@nucleus - CDK6_Thr_pho:cyclin D1*:p27Kip1*@nucleus - CDK4_Thr172_pho:cyclin D1*:p27Kip1*@nucleus - CDK4:cyclin D1*:p21Cip*@nucleus - CDK6:cyclin D1*:p21Cip*@nucleus - CDK6_Thr_pho:cyclin D1*:p27Kip1*@nucleus -> DP2*:E2F4:p107*__pho@nucleus