Single-step detection of mutant huntingtin in animal and human tissues: a bioassay for Huntington's disease.
The genetic mutation causing Huntington's disease is a polyglutamine expansion in the huntingtin protein where more than 37 glutamines cause disease by formation of toxic intracellular fragments, aggregates, and cell death. Despite a clear pathogenic role for mutant huntingtin, understanding huntingtin expression during the presymptomatic phase of the disease or during disease progression has remained obscure. Central to clarifying the role in the pathomechanism of disease is the ability to easily and accurately measure mutant huntingtin in accessible human tissue samples as well as cell and animal models. Here we describe a highly sensitive time-resolved Förster resonance energy transfer (FRET) assay for quantification of soluble mutant huntingtin in brain, plasma, and cerebrospinal fluid. Surprisingly, in mice, soluble huntingtin levels decrease during disease progression, inversely correlating with brain aggregate load. Mutant huntingtin is easily detected in human brain and blood-derived fractions, providing a utility to assess mutant huntingtin expression during disease course as well as a pharmacodynamic marker for disease-modifying therapeutics targeting expression, cleavage, or degradation of mutant huntingtin. The design of the homogeneous one-step method for huntingtin detection is such that it can be easily applied to measure other proteins of interest.
Weiss
Andreas
A
Novartis Institutes for BioMedical Research, Basel, Switzerland.
Abramowski
Dorothée
D
Bibel
Miriam
M
Bodner
Ruth
R
Chopra
Vanita
V
DiFiglia
Marian
M
Fox
Jonathan
J
Kegel
Kimberly
K
Klein
Corinna
C
Grueninger
Stephan
S
Hersch
Steven
S
Housman
David
D
Régulier
Etienne
E
Rosas
H Diana
HD
Stefani
Muriel
M
Zeitlin
Scott
S
Bilbe
Graeme
G
Paganetti
Paolo
P
D000328:Adult; D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000378:metabolism; D002460:Cell Line; D018450:Disease Progression; D053595:Embryonic Stem Cells / Q000378:metabolism; D005091:Exons; D005260:Female; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D015870:Gene Expression; D006801:Humans; D000071058:Huntingtin Protein; D006816:Huntington Disease / Q000097:blood / Q000134:cerebrospinal fluid / Q000175:diagnosis*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism; D050505:Mutant Proteins / Q000302:isolation & purification* / Q000378:metabolism; D019579:Neocortex / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D012680:Sensitivity and Specificity; D013997:Time Factors; D055815:Young Adult
C086055:HTT protein, human; C506812:Htt protein, mouse; D000071058:Huntingtin Protein; D050505:Mutant Proteins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins