Protein kinase C gamma mutations in spinocerebellar ataxia 14 increase kinase activity and alter membrane targeting.
The protein kinase C gamma (PKCgamma) gene is mutated in spinocerebellar ataxia type 14 (SCA14). In this study, we investigated the effects of two SCA14 missense mutations, G118D and C150F, on PKCgamma function. We found that these mutations increase the intrinsic activity of PKCgamma. Direct visualization of labelled PKCgamma in living cells demonstrates that the mutant protein translocates more rapidly to selected regions of the plasma membrane in response to Ca2+ influx. These results point to specific alterations in mutant PKCgamma function that could lead to the selective neuronal degeneration of SCA14.
Verbeek
D S
DS
Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda 20892, USA.
Knight
M A
MA
Harmison
G G
GG
Fischbeck
K H
KH
Howell
B W
BW
D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002118:Calcium / Q000494:pharmacology; D002462:Cell Membrane / Q000201:enzymology; D002522:Chlorocebus aethiops; D006801:Humans; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D010766:Phosphorylation; D011493:Protein Kinase C / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D020754:Spinocerebellar Ataxias / Q000201:enzymology / Q000235:genetics*; D014178:Translocation, Genetic / Q000187:drug effects
C087857:protein kinase C gamma; D011493:Protein Kinase C; D002118:Calcium