TY - JOUR
T1 - Expression of the huntington's disease (IT15) protein product in HD patients
AU - Schilling, Gabrlele
AU - Sharp, Alan H.
AU - Loev, Scott J.
AU - Wagster, Molly V.
AU - Li, Shi Hua
AU - Stine, O. Colin
AU - Ross, Christopher A.
N1 - Funding Information:
This research was supported by NS 16375, funds from the Departments of Psychiatry and Neuroscience, a bequest from the estate of Nora Mae Gee and funds from the Washington Chapter of the HDSA. We thank Dr Russ Margolis for expert advice on the scanner and quantification. We thank Dr Juan Troncoso of the Johns Hopkins Brain Research Center for providing brain tissues from control cases. We appreciate the assistance of Joyce Kotzuk in securing the human tissue samples. We thank Prof. Bartholmes of the private University of Witten/Herdecke, Germany, for discussions.
Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 1995/8
Y1 - 1995/8
N2 - Huntington's disease (HD) is an inherited, neurodegenerative disorder caused by expansion of a CAG repeat in the IT15 gene, leading to an expanded glutamine repeat in the HD protein. The mechanism by which the expanded repeat causes expression of the disease is not known, though there do not appear to be changes in the mRNA levels. We have conducted quantitative Western blot analyses of HD patients and controls. Expression of the IT15 protein is essentially equal in control and HD frontal cortex. In caudate from HD patients, IT15 protein is decreased in parallel with the decrease in a neuronal marker, suggesting that loss of IT15 protein is secondary to neuronal loss. In order to determine expression of the two alleles of the IT15 protein we used Western blots of 4% polyacrylamide gels. Both alleles of the IT15 protein were expressed at similar levels in HD lymphoblastoid cell lines and HD post-mortem hippocampus and cerebellum (regions relatively spared in HD), indicating that even very long CAG repeats can be translated into polyglutamine. In contrast, in cerebral cortex and caudate (regions severely affected in HD), in the longer expanded repeat cases the expanded allele of the IT15 protein was present at a significantly lower level (compared with the normal length allele), often with a smear of more slowly migrating reactivity above it. These data suggest the possibility of altered structure, abnormal processing or abnormality of protein-protein interactions involving the IT15 protein with the expanded glutamine repeat.
AB - Huntington's disease (HD) is an inherited, neurodegenerative disorder caused by expansion of a CAG repeat in the IT15 gene, leading to an expanded glutamine repeat in the HD protein. The mechanism by which the expanded repeat causes expression of the disease is not known, though there do not appear to be changes in the mRNA levels. We have conducted quantitative Western blot analyses of HD patients and controls. Expression of the IT15 protein is essentially equal in control and HD frontal cortex. In caudate from HD patients, IT15 protein is decreased in parallel with the decrease in a neuronal marker, suggesting that loss of IT15 protein is secondary to neuronal loss. In order to determine expression of the two alleles of the IT15 protein we used Western blots of 4% polyacrylamide gels. Both alleles of the IT15 protein were expressed at similar levels in HD lymphoblastoid cell lines and HD post-mortem hippocampus and cerebellum (regions relatively spared in HD), indicating that even very long CAG repeats can be translated into polyglutamine. In contrast, in cerebral cortex and caudate (regions severely affected in HD), in the longer expanded repeat cases the expanded allele of the IT15 protein was present at a significantly lower level (compared with the normal length allele), often with a smear of more slowly migrating reactivity above it. These data suggest the possibility of altered structure, abnormal processing or abnormality of protein-protein interactions involving the IT15 protein with the expanded glutamine repeat.
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U2 - 10.1093/hmg/4.8.1365
DO - 10.1093/hmg/4.8.1365
M3 - Article
C2 - 7581375
AN - SCOPUS:0029092340
SN - 0964-6906
VL - 4
SP - 1365
EP - 1371
JO - Human molecular genetics
JF - Human molecular genetics
IS - 8
ER -