A protein interaction network links GIT1, an enhancer of huntingtin aggregation, to Huntington's disease.
Analysis of protein-protein interactions (PPIs) is a valuable approach for characterizing proteins of unknown function. Here, we have developed a strategy combining library and matrix yeast two-hybrid screens to generate a highly connected PPI network for Huntington's disease (HD). The network contains 186 PPIs among 35 bait and 51 prey proteins. It revealed 165 new potential interactions, 32 of which were confirmed by independent binding experiments. The network also permitted the functional annotation of 16 uncharacterized proteins and facilitated the discovery of GIT1, a G protein-coupled receptor kinase-interacting protein, which enhances huntingtin aggregation by recruitment of the protein into membranous vesicles. Coimmunoprecipitations and immunofluorescence studies revealed that GIT1 and huntingtin associate in mammalian cells under physiological conditions. Moreover, GIT1 localizes to neuronal inclusions, and is selectively cleaved in HD brains, indicating that its distribution and function is altered during disease pathogenesis.
Goehler
Heike
H
Max-Delbrueck-Center for Molecular Medicine, 13125 Berlin-Buch, Germany.
Lalowski
Maciej
M
Stelzl
Ulrich
U
Waelter
Stephanie
S
Stroedicke
Martin
M
Worm
Uwe
U
Droege
Anja
A
Lindenberg
Katrin S
KS
Knoblich
Maria
M
Haenig
Christian
C
Herbst
Martin
M
Suopanki
Jaana
J
Scherzinger
Eberhard
E
Abraham
Claudia
C
Bauer
Bianca
B
Hasenbank
Renate
R
Fritzsche
Anja
A
Ludewig
Andreas H
AH
Büssow
Konrad
K
Buessow
Konrad
K
Coleman
Sarah H
SH
Gutekunst
Claire-Anne
CA
Landwehrmeyer
Bernhard G
BG
Lehrach
Hans
H
Wanker
Erich E
EE
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D001665:Binding Sites; D019556:COS Cells; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D002522:Chlorocebus aethiops; D020690:GTPase-Activating Proteins / Q000737:chemistry / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D000071058:Huntingtin Protein; D006816:Huntington Disease / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D016716:PC12 Cells; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism*; D011233:Precipitin Tests; D011392:Proline / Q000737:chemistry; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014018:Tissue Distribution; D020798:Two-Hybrid System Techniques
D048868:Adaptor Proteins, Signal Transducing; D000911:Antibodies, Monoclonal; D018797:Cell Cycle Proteins; C485647:GIT1 protein, human; D020690:GTPase-Activating Proteins; C120766:Git1 protein, mouse; C485648:Git1 protein, rat; C086055:HTT protein, human; C506812:Htt protein, mouse; C499524:Htt protein, rat; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; D011392:Proline; D005978:Glutathione