title: Development of 4-methoxy-7-nitroindolinyl (MNI)-caged auxins which are extremely stable in planta.
abstract: Phytohormone auxin is a master regulator in plant growth and development. Regulation of cellular auxin level plays a central role in plant development. Auxin polar transport system modulates an auxin gradient that determines plant developmental process in response to environmental conditions and developmental programs. Photolabile caged auxins allow optical control of artificial auxin gradients at cellular resolution. Especially, two-photon uncaging system achieves high spatiotemporal control of photolysis reaction at two-photon cross-section. However, the development of caged versions of auxin has been limited by the instability of the caged auxins to higher plant metabolic activities. Here, we describe the synthesis and application of highly stable caged auxins, 4-methoxy-7-nitroindolinyl (MNI)-caged auxins. Natural auxin, indole 3-acetic acid, and two synthetic auxins, 1-NAA and 2,4-D were caged by MNI caging group. MNI-caged auxins showed a high stability in planta and a rapid release the original auxin when photolyzed. We demonstrated that optical control of auxin-responsive gene expression and auxin-related physiological responses by using MNI-caged auxins. We anticipate that MNI-caged auxins will be an effective tool for high-resolution control of endogenous auxin level.
authors.affiliation: Department of Biochemistry, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan. Electronic address: hayashi@dbc.ous.ac.jp.
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Hayashi
authors.affiliation: Department of Biochemistry, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Kusaka
authors.affiliation: Department of Biochemistry, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan.
authors.forename: Soma
authors.initials: S
authors.lastname: Yamasaki
authors.affiliation: Section of Cell and Developmental Biology, University of California at San Diego, La Jolla, CA 92093-0116, United States.
authors.forename: Yunde
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Biochemistry, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nozaki
mesh_terms: D017360:Arabidopsis / Q000737:chemistry* / Q000378:metabolism; D007210:Indoleacetic Acids / Q000737:chemistry* / Q000378:metabolism; D007211:Indoles / Q000737:chemistry*; D010782:Photolysis; D010937:Plant Growth Regulators / Q000737:chemistry* / Q000378:metabolism
chemical_list: D007210:Indoleacetic Acids; D007211:Indoles; D010937:Plant Growth Regulators
keywords: Auxin; Caged auxin; Plant hormone; Two-photon uncaging