The TSC1 gene product hamartin interacts with NADE.
Hamartomatous brain lesions are a hallmark of brain pathology of tuberous sclerosis complex (TSC). To elucidate the mechanism of tumor development in the brain of TSC, we identified NADE (p75NTR-associated cell death executor) as an interactor for TSC1 gene product hamartin using a yeast two-hybrid system. In a pull-down assay, endogenous NADE was purified with the immobilized coiled-coil domain (CCD) of hamartin from the PC12h cell lysate. Immunofluorescence and immunoprecipitation confirmed the interaction of hamartin and NADE in cultured neurons and mouse brain lysate. Hamartin constitutively associated with NADE to prevent its proteasomal degradation. Suppression of hamartin with TSC1 small interfering RNA (siRNA) caused reduction of NADE and failed to lead to NGF-induced apoptosis in PC12h cells. These results indicate that hamartin binds to NADE to regulate neuronal cell function and loss of this association is likely to contribute to the brain pathology in TSC.
Yasui
Sakiko
S
Department of Neurobiology, School of Life Sciences, Tottori University Faculty of Medicine, Yonago 683-8503, Japan.
Tsuzaki
Kokoro
K
Ninomiya
Haruaki
H
Floricel
Florin
F
Asano
Yasuo
Y
Maki
Hirotoshi
H
Takamura
Ayumi
A
Nanba
Eiji
E
Higaki
Katsumi
K
Ohno
Kousaku
K
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D019556:COS Cells; D002531:Cerebellum / Q000166:cytology; D002522:Chlorocebus aethiops; D006801:Humans; D007668:Kidney / Q000166:cytology; D051379:Mice; D008810:Mice, Inbred C57BL; D020932:Nerve Growth Factor / Q000378:metabolism; D016716:PC12 Cells; D017434:Protein Structure, Tertiary; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D014402:Tuberous Sclerosis / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D000077004:Tuberous Sclerosis Complex 1 Protein; D025521:Tumor Suppressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
D051017:Apoptosis Regulatory Proteins; C410727:BEX3 protein, human; D011993:Recombinant Fusion Proteins; C000624650:TSC1 protein, human; C000624651:Tsc1 protein, mouse; C000624652:Tsc1 protein, rat; D000077004:Tuberous Sclerosis Complex 1 Protein; D025521:Tumor Suppressor Proteins; D020932:Nerve Growth Factor