Reference - Detail
|Author||Templeton GW, Nimick M, Morrice N, Campbell D, Goudreault M, Gingras AC, Takemiya A, Shimazaki K, Moorhead GB.|
|Title||Identification and characterization of AtI-2, an Arabidopsis homologue of an ancient protein phosphatase 1 (PP1) regulatory subunit.|
PP1 (protein phosphatase 1) is among the most conserved enzymes known, with one or more isoforms present in all sequenced eukaryotic genomes. PP1 dephosphorylates specific serine/threonine phosphoproteins as defined by associated regulatory or targeting subunits. In the present study we performed a PP1-binding screen to find putative PP1 interactors in Arabidopsis thaliana and uncovered a homologue of the ancient PP1 interactor, I-2 (inhibitor-2). Bioinformatic analysis revealed remarkable conservation of three regions of plant I-2 that play key roles in binding to PP1 and regulating its function. The sequence-related properties of plant I-2 were compared across eukaryotes, indicating a lack of I-2 in some species and the emergence points from key motifs during the evolution of this ancient regulator. Biochemical characterization of AtI-2 (Arabidopsis I-2) revealed its ability to inhibit all plant PP1 isoforms and inhibitory dependence requiring the primary interaction motif known as RVXF. Arabidopsis I-2 was shown to be a phosphoprotein in vivo that was enriched in the nucleus. TAP (tandem affinity purification)-tag experiments with plant I-2 showed in vivo association with several Arabidopsis PP1 isoforms and identified other potential I-2 binding proteins.
|MeSH||Amino Acid Sequence Arabidopsis / genetics Arabidopsis / metabolism* Arabidopsis Proteins / chemistry* Arabidopsis Proteins / genetics Arabidopsis Proteins / isolation & purification Arabidopsis Proteins / metabolism Cell Line Cell Nucleus / metabolism Computational Biology / methods Databases, Protein Molecular Sequence Data Phosphoproteins / chemistry Phosphoproteins / genetics Phosphoproteins / isolation & purification Phosphoproteins / metabolism Phylogeny Plant Epidermis / cytology Plant Epidermis / metabolism Plant Leaves / cytology Plant Leaves / metabolism Plant Structures / metabolism Protein Isoforms / genetics Protein Isoforms / isolation & purification Protein Isoforms / metabolism Protein Phosphatase 1 / chemistry* Protein Phosphatase 1 / genetics Protein Phosphatase 1 / isolation & purification Protein Phosphatase 1 / metabolism Protein Subunits / chemistry Protein Subunits / genetics Protein Subunits / isolation & purification Protein Subunits / metabolism Protein Transport Recombinant Fusion Proteins / metabolism Sequence Alignment Sequence Homology, Amino Acid|
|WOS Category||BIOCHEMISTRY & MOLECULAR BIOLOGY|
|Arabidopsis / Cultured plant cells, genes||pda02740|