Commitment of 1-Methyl-4-phenylpyrinidinium Ion-induced Neuronal Cell Death by Proteasome-mediated Degradation of p35 Cyclin-dependent Kinase 5 Activator

Endo, Ryo; Saito, Taro; Asada, Akiko; Kawahara, Hiroyuki; Ohshima, Toshio; Hisanaga, Shin Ichi

doi:10.1074/jbc.m109.026443

Cited by 28 publications

(26 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…cDNA encoding a small hairpin RNA (shRNA) against Rab11A (target sequence: 5Ј-TCTGGAAAGCAAGAGT ACC-3Ј) was inserted into pSilencer 2.1-U6 neo vector (Applied Biosystems). shRNA against p35 (target sequence; 5Ј-CAGCTACCAGAGCA ACATCGC-3Ј) has been described previously (Endo et al, 2009). The LMTK1 alanine mutant and the phosphorylation-mimic aspartic acid mutant at Ser34 have been described Tsutsumi et al, 2010).…”

Section: Methodsmentioning

confidence: 99%

“…If this were the case, then the downregulation of Cdk5 activity should change the axonal outgrowth activity of LMTK1-WT to that of LMTK1-S34A in neurons. We performed this experiment by the knockdown of p35, a major Cdk5 activator (Endo et al, 2009). Decreased Cdk5 activity by p35 knockdown indeed converted the axonal outgrowth activity of LMTK1-WT from the LMTK1-S34D type to the LMTK1-S34A type (Fig.…”

Section: Effect Of Phosphorylation Of Lmtk1 At Ser34 On Axonal Outgrowthmentioning

confidence: 99%

See 1 more Smart Citation

LMTK1/AATYK1 Is a Novel Regulator of Axonal Outgrowth That Acts via Rab11 in a Cdk5-Dependent Manner

et al. 2012

View full text Add to dashboard Cite

Axonal outgrowth is a coordinated process of cytoskeletal dynamics and membrane trafficking; however, little is known about proteins responsible for regulating the membrane supply. LMTK1 (lemur kinase 1)/AATYK1 (apoptosis-associated tyrosine kinase 1) is a serine/ threonine kinase that is highly expressed in neurons. We recently reported that LMTK1 plays a role in recycling endosomal trafficking in CHO-K1 cells. Here we explore the role of LMTK1 in axonal outgrowth and its regulation by Cdk5 using mouse brain cortical neurons. LMTK1 was expressed and was phosphorylated at Ser34, the Cdk5 phosphorylation site, at the time of axonal outgrowth in culture and colocalized with Rab11A, the small GTPase that regulates recycling endosome traffic, at the perinuclear region and in the axon. Overexpression of the unphosphorylated mutant LMTK1-S34A dramatically promoted axonal outgrowth in cultured neurons. Enhanced axonal outgrowth was diminished by the inactivation of Rab11A, placing LMTK1 upstream of Rab11A. Unexpectedly, the downregulation of LMTK1 by knockdown or gene targeting also significantly enhanced axonal elongation. Rab11A-positive vesicles were transported anterogradely more quickly in the axons of LMTK1-deficient neurons than in those of wild-type neurons. The enhanced axonal outgrowth was reversed by LMTK1-WT or the LMTK1-S34D mutant, which mimics the phosphorylated state, but not by LMTK1-S34A. Thus, LMTK1 can negatively control axonal outgrowth by regulating Rab11A activity in a Cdk5-dependent manner, and Cdk5-LMTK1-Rab11 is a novel signaling pathway involved in axonal outgrowth.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Effect Of Phosphorylation Of Lmtk1 At Ser34 On Axonal Outgrowthmentioning

confidence: 99%

LMTK1/AATYK1 Is a Novel Regulator of Axonal Outgrowth That Acts via Rab11 in a Cdk5-Dependent Manner

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Neurons (2 ϫ 10 5 per ml) were seeded on 35 mm glass-bottom dishes. The medium was then changed to neurobasal medium supplemented with B27 (Invitrogen) and 1 mM L-glutamine (Endo et al, 2009). Cells were transiently transfected with Tau WT, 3A, or 3D with Lipofectamine 2000 (Invitrogen).…”

Section: Construction Of Expression Vectors For Tau Proteinsmentioning

confidence: 99%

Regulation of Mitochondrial Transport and Inter-Microtubule Spacing by Tau Phosphorylation at the Sites Hyperphosphorylated in Alzheimer's Disease

Shahpasand

Uemura²,

Saito³

et al. 2012

J. Neurosci.

172

140

View full text Add to dashboard Cite

The microtubule-associated protein Tau is a major component of the neurofibrillary tangles that serve as a neuropathological hallmark of Alzheimer's disease. Tau is a substrate for protein phosphorylation at multiple sites and occurs in tangles in a hyperphosphorylated state. However, the physiological functions of Tau phosphorylation or how it may contribute mechanistically to Alzheimer's pathophysiology are not completely understood. Here, we examined the function of human Tau phosphorylation at three sites, Ser199, Ser202, and Thr205, which together comprise the AT8 sites that mark abnormal phosphorylation in Alzheimer's disease. Overexpression of wild-type Tau or mutated forms in which these sites had been changed to either unphosphorylatable alanines or phosphomimetic aspartates inhibited mitochondrial movement in the neurite processes of PC12 cells as well as the axons of mouse brain cortical neurons. However, the greatest effects on mitochondrial translocation were induced by phosphomimetic mutations. These mutations also caused expansion of the space between microtubules in cultured cells when membrane tension was reduced by disrupting actin filaments. Thus, Tau phosphorylation at the AT8 sites may have meaningful effects on mitochondrial movement, likely by controlling microtubule spacing. Hyperphosphorylation of the AT8 sites may contribute to axonal degeneration by disrupting mitochondrial transport in Alzheimer's disease.

show abstract

“…Cortical neurons were prepared from mouse brains at embryonic day 17 as described previously (Endo et al, 2009). The p35 knockdown vector was reported previously (Endo et al, 2009).…”

Section: Neuronal Cultures and Transfectionmentioning

confidence: 99%

Cdk5 phosphorylation of its activators p35 and p39 determines subcellular location of the holokinase in a phosphorylation site-specific manner

Asada¹,

Saito²,

Hisanaga³

2012

Journal of Cell Science

Self Cite

View full text Add to dashboard Cite

SummaryCdk5 is a member of the cyclin-dependent kinase (Cdk) family, which is activated by neuronal activators p35 or p39. Cdk5 regulates a variety of neuronal activities including migration, synaptic activity and neuronal death. p35 and p39 impart cytoplasmic membrane association of p35-Cdk5 and p39-Cdk5, respectively, through their myristoylation, but it is not clearly understood how the cellular localization is related to different functions. We investigated the role of Cdk5 activity in the subcellular localization of p35-Cdk5 and p39-Cdk5. Cdk5 activity affected the localization of p35-Cdk5 and p39-Cdk5 through phosphorylation of p35 or p39. Using unphosphorylated or phosphomimetic mutants of p35 and p39, we found that phosphorylation at Ser8, common to p35 and p39, by Cdk5 regulated the cytoplasmic localization and perinuclear accumulation of unphosphorylated S8A mutants, and whole cytoplasmic distribution of phosphomimetic S8E mutants. Cdk5 activity was necessary to retain Cdk5-activator complexes in the cytoplasm. Nevertheless, small but distinct amounts of p35 and p39 were detected in the nucleus. In particular, nuclear p35 and p39 were increased when the Cdk5 activity was inhibited. p39 had a greater propensity to accumulate in the nucleus than p35, and phosphorylation at Thr84, specific to p39, regulated the potential nuclear localization activity of the Lys cluster in p39. These results suggest that the subcellular localization of the Cdk5-activator complexes is determined by its kinase activity, and also implicate a role for p39-Cdk5 in the nucleus.

show abstract

Commitment of 1-Methyl-4-phenylpyrinidinium Ion-induced Neuronal Cell Death by Proteasome-mediated Degradation of p35 Cyclin-dependent Kinase 5 Activator

Abstract: The dysfunction of proteasomes and mitochondria has been implicated in the pathogenesis of Parkinson disease. However, the mechanism by which this dysfunction causes neuronal cell death is unknown. We studied the role of cyclin

Cited by 28 publications

References 53 publications

LMTK1/AATYK1 Is a Novel Regulator of Axonal Outgrowth That Acts via Rab11 in a Cdk5-Dependent Manner

LMTK1/AATYK1 Is a Novel Regulator of Axonal Outgrowth That Acts via Rab11 in a Cdk5-Dependent Manner

Regulation of Mitochondrial Transport and Inter-Microtubule Spacing by Tau Phosphorylation at the Sites Hyperphosphorylated in Alzheimer's Disease

Cdk5 phosphorylation of its activators p35 and p39 determines subcellular location of the holokinase in a phosphorylation site-specific manner

Contact Info

Product

Resources

About