title: Auxin Extraction and Purification Based on Recombinant Aux/IAA Proteins.
abstract: BACKGROUND
  Indole-3-acetic acid (IAA) extraction and purification are of great importance in auxin research, which is a hot topic in the plant growth and development field. Solid-phase extraction (SPE) is frequently used for IAA extraction and purification. However, no IAA-specific SPE columns are commercially available at the moment. Therefore, the development of IAA-specific recognition materials and IAA extraction and purification methods will help researchers meet the need for more precise analytical methods for research on phytohormones.
  
  
  RESULTS
  Since the AUXIN RESISTANT/INDOLE-3-ACETIC ACID INDUCIBLE (Aux/IAA) proteins show higher specific binding capability with auxin, recombinant IAA1, IAA7 and IAA28 proteins were used as sorbents to develop an IAA extraction and purification method. A GST tag was used to solidify the recombinant protein in a column. Aux/IAA proteins solidified in a column have successfully trapped trace IAA in aqueous solutions. The IAA7 protein showed higher IAA binding capability than the other proteins tested. In addition, expression of the IAA7 protein inDrosophilaSchneider 2 (S2) cells produced better levels of binding than IAA7 expressed inE. coli.
  
  
  CONCLUSIONS
  This work validated the potential of Aux/IAA proteins to extract and purify IAA from crude plant extracts once we refined the techniques for these processes.
authors.affiliation: Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Su
authors.affiliation: Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha, China.
authors.forename: Weigui
authors.initials: W
authors.lastname: Luo
authors.affiliation: Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha, China.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Chen
authors.affiliation: Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha, China.
authors.forename: Huizhen
authors.initials: H
authors.lastname: Liu
authors.affiliation: Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha, China.
authors.forename: Yueqing
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha, China ; Hunan Co-Innovation Center for Utilization of Botanical Functional Ingredients, Changsha, China.
authors.forename: Wanhuang
authors.initials: W
authors.lastname: Lin
authors.affiliation: Hunan Provincial Key Laboratory of Phytohormones and Growth Development, Hunan Agricultural University, Changsha, China ; Hunan Co-Innovation Center for Utilization of Botanical Functional Ingredients, Changsha, China.
authors.forename: Langtao
authors.initials: L
authors.lastname: Xiao
keywords: Aux/IAA; Binding Capability; Extraction and Purification; IAA; SPE