Neuronal intranuclear inclusions in spinocerebellar ataxia type 2: triple-labeling immunofluorescent study.
Spinocerebellar ataxia type 2 (SCA2) is associated with an expansion of CAG/polyglutamine-repeat of a gene of unknown function. We performed an immunohistochemical study to identify the immunolocalization of the disease protein ataxin-2 in normal and SCA2 patients. Although normal and expanded ataxin-2 were ubiquitously localized to the cytoplasm of neurons, ubiquitinated intranuclear inclusions were observed selectively in 1-2% of neurons of affected brain regions except the cerebellum. Triple-labeling immunofluorescence revealed that ataxin-2, expanded polyglutamine and ubiquitin were colocalized to these neuronal intranuclear inclusions (NIs), indicating that SCA2 shares morphological characteristics common to other neurological disorders associated with an expansion of CAG/polyglutamine-repeat. Lack of NIs in the cerebellar lesion, however, suggests the discrepancy between formation of NIs and neuronal degeneration in SCA2.
Koyano
S
S
Department of Neurology and Psychiatry, Kanagawa Rehabilitation Center, Atsugi, Japan.
Uchihara
T
T
Fujigasaki
H
H
Nakamura
A
A
Yagishita
S
S
Iwabuchi
K
K
D000067528:Ataxins; D002102:Cadaver; D006801:Humans; D007150:Immunohistochemistry; D002479:Inclusion Bodies / Q000473:pathology*; D009419:Nerve Tissue Proteins; D009474:Neurons / Q000473:pathology*; D010455:Peptides / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D012016:Reference Values; D020754:Spinocerebellar Ataxias / Q000378:metabolism / Q000473:pathology*; D014018:Tissue Distribution; D014452:Ubiquitins / Q000378:metabolism
D000067528:Ataxins; D009419:Nerve Tissue Proteins; D010455:Peptides; D011506:Proteins; D014452:Ubiquitins; C097188:polyglutamine