[Screening for proteins interacting with ataxin-3, the gene product of SCA3/MJD].
OBJECTIVE
To screen for proteins interacting with ataxin-3 by yeast two-hybrid system 3, and to discuss the function of ataxin-3 and pathogenesis of spinocerebellar ataxia type 3 and Machado-Joseph disease (SCA3/MJD).


METHODS
First we sub-cloned the full reading frame of both wild-type and mutant ataxin-3 into carrier pGBKT7 (ataxin-3-bait), and then screened human brain cDNA library with ataxin-3-bait.


RESULTS
We found five positive clones in 6.5 x 10(6) transformers. After sequencing, we knew all of them were novel ataxin-3 interacting proteins. Three were corresponded to the known sequences coding the known proteins, which were human Rho GDP dissociation inhibitor alpha, small ubiquitin-like modifier 1, and human neuronal amiloride-sensitive cation channel 2. Another two of the five were unknown.


CONCLUSIONS
Small ubiquitin-like modifier 1 probably interacted with ataxin-3, suggesting that the sumoylation probably participated in post-translation modifying of ataxin-3 and pathogenesis of SCA3/MJD.
Department of Neurology, Xiangya Hospital, China. shenlu2505@yahoo.com.cn
Lu
L
Shen
Bei-sha
BS
Tang
Jian-guang
JG
Tang
Hong
H
Jiang
Cheng
C
Wang
Hai-yan
HY
Fang
D000067699:Ataxin-3; D001921:Brain / Q000378:metabolism*; D015723:Gene Library; D006801:Humans; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D025941:Protein Interaction Mapping; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D013132:Spinocerebellar Degenerations / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques; D015003:Yeasts / Q000235:genetics
D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D012097:Repressor Proteins; C092341:ATXN3 protein, human; D000067699:Ataxin-3