title: Structure of the Arabidopsis thaliana TOP2 oligopeptidase.
abstract: Thimet oligopeptidase (TOP) is a zinc-dependent metallopeptidase. Recent studies suggest that Arabidopsis thaliana TOP1 and TOP2 are targets for salicylic acid (SA) binding and participate in SA-mediated plant innate immunity. The crystal structure of A. thaliana TOP2 has been determined at 3.0 Å resolution. Comparisons to the structure of human TOP revealed good overall structural conservation, especially in the active-site region, despite their weak sequence conservation. The protein sample was incubated with the photo-activated SA analog 4-azido-SA and exposed to UV irradiation before crystallization. However, there was no conclusive evidence for the binding of SA based on the X-ray diffraction data. Further studies are needed to elucidate the molecular mechanism of how SA regulates the activity of A. thaliana TOP1 and TOP2.
authors.affiliation: Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
authors.forename: Ruiying
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
authors.forename: Krithika
authors.initials: K
authors.lastname: Rajagopalan
authors.affiliation: Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
authors.forename: Kianoush
authors.initials: K
authors.lastname: Sadre-Bazzaz
authors.affiliation: The Boyce Thompson Institute for Plant Research, Tower Road, Ithaca, NY 14850, USA.
authors.forename: Magali
authors.initials: M
authors.lastname: Moreau
authors.affiliation: The Boyce Thompson Institute for Plant Research, Tower Road, Ithaca, NY 14850, USA.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Klessig
authors.affiliation: Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
authors.forename: Liang
authors.initials: L
authors.lastname: Tong
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000235:genetics; D006801:Humans; D008666:Metalloendopeptidases / Q000737:chemistry* / Q000235:genetics; D017433:Protein Structure, Secondary; D014961:X-Ray Diffraction
chemical_list: D029681:Arabidopsis Proteins; D008666:Metalloendopeptidases; C022510:thimet oligopeptidase
keywords: Arabidopsis thaliana; thimet oligopeptidase (TOP)