Polyglutamine repeat length-dependent proteolysis of huntingtin.
Amino-terminal fragments of huntingtin, which contain the expanded polyglutamine repeat, have been proposed to contribute to the pathology of Huntington's disease (HD). Data supporting this claim have been generated from patients with HD in which truncated amino-terminal fragments forming intranuclear inclusions have been observed, and from animal and cell-based models of HD where it has been demonstrated that truncated polyglutamine-containing fragments of htt are more toxic than full-length huntingtin. We report here the identification of a region within huntingtin, spanning from amino acids 63 to 111, that is cleaved in cultured cells to generate a fragment of similar size to those observed in patients with HD. Importantly, proteolytic cleavage within this region appears dependent upon the length of the polyglutamine repeat within huntingtin, with pathological polyglutamine repeat-containing huntingtin being more efficiently cleaved than huntingtin containing polyglutamine repeats of nonpathological size.
Sun
Banghua
B
Amgen Inc., Thousand Oaks, California 91320, USA.
Fan
Wei
W
Balciunas
Aldona
A
Cooper
Jillian K
JK
Bitan
Gal
G
Steavenson
Shirley
S
Denis
Paul E
PE
Young
Yunjen
Y
Adler
Beverly
B
Daugherty
Larry
L
Manoukian
Raffi
R
Elliott
Gary
G
Shen
Wenyan
W
Talvenheimo
Jane
J
Teplow
David B
DB
Haniu
Mitsuru
M
Haldankar
Raj
R
Wypych
Jette
J
Ross
Christopher A
CA
Citron
Martin
M
Richards
William G
WG
D000595:Amino Acid Sequence; D000818:Animals; D002154:Calpain / Q000378:metabolism; D002460:Cell Line; D003342:Corpus Striatum / Q000166:cytology; D018604:Epitope Mapping; D017353:Gene Deletion; D000071058:Huntingtin Protein; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism*; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D010455:Peptides / Q000235:genetics* / Q000378:metabolism*; D012091:Repetitive Sequences, Nucleic Acid
C506812:Htt protein, mouse; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D010446:Peptide Fragments; D010455:Peptides; C097188:polyglutamine; D002154:Calpain