Nerve growth factor induces cell cycle arrest of astrocytes

ANDREA BEATRÍZ CRAGNOLINI; MARTA VOLOSIN; YANGYANG HUANG; WILMA J. FRIEDMAN

DEVELOPMENTAL NEUROBIOLOGY

JOHN WILEY & SONS INC

Año: 2012 vol. 72 p. 766 - 776

1932-8451

Neurotrophins can influence multiple cellular functions depending on the cellular context and the specific receptors they interact with. These neurotrophic factors have been extensively studied for their ability to support neuronal survival via Trk receptors, and to induce apoptosis via the p75(NTR) . However, the p75(NTR) is also detected on cell populations that do not undergo apoptosis in response to neurotrophins. In particular, we have detected p75(NTR) expression on astrocytes during development and after seizure-induced injury. In this study we the role of NGF in regulating astrocyte proliferation, and in influencing specific aspects of the cell cycle. We demonstrate that NGF prevents the induction of cyclins and their association with specific cyclin-dependent kinases, and thereby prevents progression through the G1 phase of the cell cycle. Since we have previously shown that p75(NTR) , but not TrkA, is expressed in astrocytes, these data suggest that activation of p75(NTR) promotes withdrawal of astrocytes from the cell cycle, which may have important consequences during development and after injury.