Arg 901 in the AE1 C-terminal tail is involved in conformational change but not in substrate binding

作者：Takazaki Shinya; Abe Yoshito^*; Yamaguchi Tomohiro; Yagi Mikako; Ueda Tadashi; Kang Dongchon; Hamasaki Naotaka

来源：Biochimica et Biophysica Acta-Biomembranes, 2012, 1818(3): 658-665.

DOI：10.1016/j.bbamem.2011.11.019

• Band 3 protein
• Anion exchange
• Membrane protein structure

In our previous paper, we demonstrated that Arg 901 in the C-terminal tail of human AE1 (band 3, anion exchanger 1) had a functional role in conformational change during anion exchange. To further examine how Arg 901 is involved in conformational change, we expressed various Arg 901 mutants and alanine mutants of the C-terminal tail (from Leu 886 to Val 911) on the plasma membrane of Saccharomyces cerevisiae and evaluated the kinetic parameters of sulfate ion transport. As a result, Vmax decreased as the hydrophobicities of the 901st and peripheral hydrophilic residues increased, indicating that the hydrophobicity of the C-terminal residue is involved in the conformational change. We also found the alkali and protease resistance of the C-terminal region after Arg 901 modification with hydroxyphenylglyoxal (HPG) or phenylglyoxal (PG), a hydrophobic reagent. These results suggested that the increased hydrophobicity of the C-terminal region around Arg 901 leads to inefficient conformational change by the newly produced hydrophobic interaction.

• 出版日期2012-3