Characterization of the protein phosphatase 1-binding motifs of inhibitor-2 and DARPP-32 by surface plasmon resonance.
KLHY is a short amino-acid sequence of inhibitor-2. This sequence is highly conserved with the protein phosphatase 1 (PP1)-binding consensus motif, RVXF. The role of this segment in binding with PP1 is ambiguous. By using surface plasmon resonance we have characterized its binding ability to PP1. Either site-directed mutagenesis or deletion of KLHY did not significantly affect the dissociation constant between PP1 and inhibitor-2. In comparison with DARPP-32, the deletion of KKIQF, a PP1-binding motif of DARPP-32, resulted in a remarkable reduction in its affinity with PP1. Our results suggested that, compared with the common RVXF motif, the KLHY sequence in intact inhibitor-2 binds weakly to PP1.
Lin
Ta-Hsien
TH
Institute of Biochemistry and Molecular Biology and Structural Biology Program, National Yang-Ming University, Taipei 11221, Taiwan, ROC.
Tsai
Pai-Chi
PC
Liu
Hsin-Tzu
HT
Chen
Yi-Chen
YC
Wang
Lan-Hsin
LH
Hsieh
Fu-Kai
FK
Huang
Hsien-Bin
HB
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32 / Q000378:metabolism*; D006801:Humans; D011485:Protein Binding; D054645:Protein Phosphatase 1 / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D011817:Rabbits; D051381:Rats; D020349:Surface Plasmon Resonance; D000097847:Protein Phosphatase Inhibitory Proteins
D051937:Dopamine and cAMP-Regulated Phosphoprotein 32; D054645:Protein Phosphatase 1; D011506:Proteins; C024833:protein phosphatase inhibitor-2; D000097847:Protein Phosphatase Inhibitory Proteins