ERK1/2 MAP kinases promote cell cycle entry by rapid, kinase-independent disruption of retinoblastoma-lamin A complexes

作者：Rodriguez Javier; Calvo Fernando; Gonzalez Jose M; Casar Berta; Andres Vicente; Crespo Piero^*

来源：The Journal of Cell Biology, 2010, 191(5): 967-979.

DOI：10.1083/jcb.201004067

As orchestrators of essential cellular processes like proliferation, ERK1/2 mitogen-activated protein kinase signals impact on cell cycle regulation. A-type lamins are major constituents of the nuclear matrix that also control the cell cycle machinery by largely unknown mechanisms. In this paper, we disclose a functional liaison between ERK1/2 and lamin A whereby cell cycle progression is regulated. We demonstrate that lamin A serves as a mutually exclusive dock for ERK1/2 and the retinoblastoma (Rb) protein. Our results reveal that, immediately after their postactivation entrance in the nucleus, ERK1/2 dislodge Rb from its interaction with lamin A, thereby facilitating its rapid phosphorylation and consequently promoting E2F activation and cell cycle entry. Interestingly, these effects are independent of ERK1/2 kinase activity. We also show that cellular transformation and tumor cell proliferation are dependent on the balance between lamin A and nuclear ERK1/2 levels, which determines Rb accessibility for phosphorylation/inactivation.

• 出版日期2010-11-29