Generation of dopamine neurons with improved cell survival and phenotype maintenance using a degradation-resistant nurr1 mutant.
Nurr1 is a transcription factor specific for the development and maintenance of the midbrain dopamine (DA) neurons. Exogenous Nurr1 in neural precursor (NP) cells induces the differentiation of DA neurons in vitro that are capable of reversing motor dysfunctions in a rodent model for Parkinson disease. The promise of this therapeutic approach, however, is unclear due to poor cell survival and phenotype loss of DA cells after transplantation. We herein demonstrate that Nurr1 proteins undergo ubiquitin-proteasome-system-mediated degradation in differentiating NP cells. The degradation process is activated by a direct Akt-mediated phosphorylation of Nurr1 proteins and can be prevented by abolishing the Akt-target sequence in Nurr1 (Nurr1(Akt)). Overexpression of Nurr1(Akt) in NP cells yielded DA neurons in which Nurr1 protein levels were maintained for prolonged periods. The sustained Nurr1 expression endowed the Nurr1(Akt)-induced DA neurons with resistance to toxic stimuli, enhanced survival, and sustained DA phenotypes in vitro and in vivo after transplantation.
Jo
A-Young
AY
Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul, Korea.
Kim
Mi-Young
MY
Lee
Hyun-Seob
HS
Rhee
Yong-Hee
YH
Lee
Jeong-Eun
JE
Baek
Kwang-Hyun
KH
Park
Chang-Hwan
CH
Koh
Hyun-Chul
HC
Shin
Incheol
I
Lee
Yong-Sung
YS
Lee
Sang-Hun
SH
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000494:pharmacology; D015153:Blotting, Western; D002070:Butadienes / Q000494:pharmacology; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000502:physiology; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D002460:Cell Line; D002470:Cell Survival / Q000235:genetics / Q000502:physiology; D002867:Chromones / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D047468:Immunoprecipitation; D008636:Mesencephalon / Q000166:cytology; D009025:Morpholines / Q000494:pharmacology; D009474:Neurons / Q000166:cytology* / Q000378:metabolism*; D009570:Nitriles / Q000494:pharmacology; D057126:Nuclear Receptor Subfamily 4, Group A, Member 2 / Q000235:genetics / Q000502:physiology*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D000081082:Phosphoinositide-3 Kinase Inhibitors; D055550:Protein Stability / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
D051792:Basic Helix-Loop-Helix Proteins; D002070:Butadienes; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D002867:Chromones; D004298:Dopamine; D004791:Enzyme Inhibitors; D005419:Flavonoids; D009025:Morpholines; D009570:Nitriles; D057126:Nuclear Receptor Subfamily 4, Group A, Member 2; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; C113580:U 0126; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one