Defining a Two-pronged Structural Model for PB1 (Phox/Bem1p) Domain Interaction in Plant Auxin Responses [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 574.19 [Unassigned]
• Thông tin xuất bản: Bethesda, Md. : Oak Ridge, Tenn. : National Institutes of Health (U.S.) ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2015
• Mô tả vật lý: Size: p. 12868-12878 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 261199
• Chủ đề: 1. 59 basic biological sciences; 2. 60 applied life sciences; 3. Nuclear magnetic resonance (nmr); 4. Plant biochemistry; 5. Plant hormone; 6. Protein structure; 7. Protein-protein interaction

Tóm tắt

Phox/Bem1p (PB1) domains are universal structural modules that use surfaces of different charge for protein-protein association. In plants, PB1-mediated interactions of auxin response factors (ARF) and auxin/indole 3-acetic acid inducible proteins regulate transcriptional events modulated by the phytohormone auxin. Here we investigate the thermodynamic and structural basis for Arabidopsis thaliana ARF7 PB1 domain self-interaction. Isothermal titration calorimetry and NMR experiments indicate that key residues on both the basic and acidic faces of the PB1 domain contribute to and organize coordinately to stabilize protein-protein interactions. Calorimetric analysis of ARF7PB1 site-directed mutants defines a two-pronged electrostatic interaction. Furthermore, the canonical PB1 interaction between a lysine and a cluster of acidic residues provides one prong with an arginine and a second cluster of acidic residues defining the other prong. Evolutionary conservation of this core recognition feature and other co-varying interface sequences allows for versatile PB1-mediated interactions in auxin signaling.