Abnormal features in mutant cerebellar Purkinje cells lacking junctophilins.
Junctional membrane complexes (JMCs) generated by junctophilins are required for Ca(2+)-mediated communication between cell-surface and intracellular channels in excitable cells. Knockout mice lacking neural junctophilins (JP-DKO) show severe motor defects and irregular cerebellar plasticity due to abolished channel crosstalk in Purkinje cells (PCs). To precisely understand aberrations in JP-DKO mice, we further analyzed the mutant PCs. During the induction of cerebellar plasticity via electrical stimuli, JP-DKO PCs showed insufficient depolarizing responses. Immunochemistry detected mild impairment in synaptic maturation and hyperphosphorylation of protein kinase Cgamma in JP-DKO PCs. Moreover, gene expression was slightly altered in the JP-DKO cerebellum. Therefore, the mutant PCs bear marginal but widespread abnormalities, all of which likely cause cerebellar motor defects in JP-DKO mice.
Ikeda
Atsushi
A
Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan.
Miyazaki
Taisuke
T
Kakizawa
Sho
S
Okuno
Yasushi
Y
Tsuchiya
Soken
S
Myomoto
Akira
A
Saito
Shin-ya
SY
Yamamoto
Tetsuji
T
Yamazaki
Tetsuo
T
Iino
Masamitsu
M
Tsujimoto
Gozoh
G
Watanabe
Masahiko
M
Takeshima
Hiroshi
H
D000200:Action Potentials / Q000235:genetics / Q000502:physiology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002531:Cerebellum / Q000166:cytology / Q000378:metabolism; D004558:Electric Stimulation; D020869:Gene Expression Profiling; D015151:Immunoblotting; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism; D011689:Purkinje Cells / Q000378:metabolism / Q000502:physiology*
D008565:Membrane Proteins; C412507:junctophilin; C087857:protein kinase C gamma; D011493:Protein Kinase C; D002118:Calcium