Structure and function of the C-terminal PABC domain of human poly(A)-binding protein.
We have determined the solution structure of the C-terminal quarter of human poly(A)-binding protein (hPABP). The protein fragment contains a protein domain, PABC [for poly(A)-binding protein C-terminal domain], which is also found associated with the HECT family of ubiquitin ligases. By using peptides derived from PABP interacting protein (Paip) 1, Paip2, and eRF3, we show that PABC functions as a peptide binding domain. We use chemical shift perturbation analysis to identify the peptide binding site in PABC and the major elements involved in peptide recognition. From comparative sequence analysis of PABC-binding peptides, we formulate a preliminary PABC consensus sequence and identify human ataxin-2, the protein responsible for type 2 spinocerebellar ataxia (SCA2), as a potential PABC ligand.
Kozlov
G
G
Department of Biochemistry, McGill University and Montreal Joint Center for Structural Biology, 3655 Promenade Sir William Osler, Montreal, QC, Canada H3G 1Y6.
Trempe
J F
JF
Khaleghpour
K
K
Kahvejian
A
A
Ekiel
I
I
Gehring
K
K
D000595:Amino Acid Sequence; D000818:Animals; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D039102:Poly(A)-Binding Proteins; D011487:Protein Conformation; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
D039102:Poly(A)-Binding Proteins; D016601:RNA-Binding Proteins