title: Evaluation of the role of Disabled-2 in nerve growth factor-mediated neurite outgrowth and cellular signalling.
abstract: Disabled-2 (DAB2) is an adapter protein that plays a key role in cell proliferation and differentiation. We reported here that DAB2 is expressed in various regions of rat central nervous system and is most abundant in the olfactory bulb. The up-regulation of DAB2 upon 5,7-dihydroxytryptamine-induced spinal cord lesion implicates that DAB2 may participate in the regulation of neuronal plasticity. To investigate DAB2 function in the regulation of neurite outgrowth, the rat p59 and p82 form of DAB2 was individually and stably expressed in the PC12 cells. Both p59 and p82 inhibited nerve growth factor (NGF)-induced neurite outgrowth concomitantly with a decrease in the expression of neuron-specific cytoskeleton protein beta-tubulin III. To unveil the molecular mechanism of DAB2 in NGF signaling, we found that RhoA-GTPase activity was up-regulated in DAB2 stable lines whereas the Ras/MAPK and PI3-kinase/Akt signaling was not affected. The inhibitory effect of DAB2 on NGF-mediated neurite outgrowth was reversed by the pretreatment of Rho-kinase (ROCK) inhibitor Y27632, implicating that DAB2 modulates RhoA/ROCK signaling. Together, this study defines a role of DAB2 in the control of neuronal plasticity and demonstrates for the first time that DAB2 is a negative regulator in NGF-mediated neurite outgrowth.
authors.affiliation: Graduate Institute of Basic Medical Sciences, Chang Gung University, Taoyuan 333, Taiwan, Republic of China.
authors.forename: Ching-Hui
authors.initials: CH
authors.lastname: Huang
authors.forename: Ju-Chien
authors.initials: JC
authors.lastname: Cheng
authors.forename: Jin-Chung
authors.initials: JC
authors.lastname: Chen
authors.forename: Ching-Ping
authors.initials: CP
authors.lastname: Tseng
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport / Q000378:metabolism*; D000577:Amides / Q000494:pharmacology; D000818:Animals; D051017:Apoptosis Regulatory Proteins; D002490:Central Nervous System / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D020932:Nerve Growth Factor / Q000494:pharmacology*; D016501:Neurites / Q000187:drug effects* / Q000378:metabolism*; D016716:PC12 Cells; D020033:Protein Isoforms / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects*; D014404:Tubulin / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D000577:Amides; D051017:Apoptosis Regulatory Proteins; C478773:Dab2 protein, mouse; D020033:Protein Isoforms; D011725:Pyridines; D014404:Tubulin; C108830:Y 27632; D020932:Nerve Growth Factor; D051057:Proto-Oncogene Proteins c-akt; D048052:Mitogen-Activated Protein Kinase 3; D020741:rho GTP-Binding Proteins