title: Functional conservation of phosphorylation-specific prolyl isomerases in plants.
abstract: The phosphorylation-specific peptidyl prolyl cis/trans isomerase (PPIase) Pin1 in humans and its homologues in yeast and animal species play an important role in cell cycle regulation. These PPIases consist of an NH(2)-terminal WW domain that binds to specific phosphoserine- or phosphothreonine-proline motifs present in a subset of phosphoproteins and a COOH-terminal PPIase domain that specifically isomerizes the phosphorylated serine/threonine-proline peptide bonds. Here, we describe the isolation of MdPin1, a Pin1 homologue from the plant species apple (Malus domestica) and show that it has the same phosphorylation-specific substrate specificity and can be inhibited by juglone in vitro, as is the case for Pin1. A search in the plant expressed sequence tag data bases reveals that the Pin1-type PPIases are present in various plants, and there are multiple genes in one organism, such as soybean (Glycine max) and tomato (Lycopersicon esculentum). Furthermore, all these plant Pin1-type PPIases, including AtPin1 in Arabidopsis thaliana, do not have a WW domain, but all contain a four-amino acid insertion next to the phospho-specific recognition site of the active site. Interestingly, like Pin1, both MdPin1 and AtPin1 are able to rescue the lethal mitotic phenotype of a temperature-sensitive mutation in the Pin1 homologue ESS1/PTF1 gene in Saccharomyces cerevisiae. However, deleting the extra four amino acid residues abolished the ability of AtPin1 to rescue the yeast mutation under non-overexpression conditions, indicating that these extra amino acids may be important for mediating the substrate interaction of plant enzymes. Finally, expression of MdPin1 is tightly associated with cell division both during apple fruit development in vivo and during cell cultures in vitro. These results have demonstrated that phosphorylation-specific PPIases are highly conserved functionally in yeast, animal, and plant species. Furthermore, the experiments suggest that although plant Pin1-type enzymes do not have a WW domain, they may fulfill the same functions as Pin1 and its homologues do in other organisms.
authors: Horticulture and Food Research Institute of New Zealand, Private Bag, 92169 Auckland, New Zealand.
authors: J L
authors: JL
authors: Yao
authors: O
authors: O
authors: Kops
authors: P J
authors: PJ
authors: Lu
authors: K P
authors: KP
authors: Lu
mesh_terms: D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins; D001483:Base Sequence; D001665:Binding Sites; D015152:Blotting, Northern; D003001:Cloning, Molecular; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000378:metabolism; D016208:Databases, Factual; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007700:Kinetics; D008938:Mitosis; D008969:Molecular Sequence Data; D009154:Mutation; D000072340:NIMA-Interacting Peptidylprolyl Isomerase; D009285:Naphthoquinones / Q000494:pharmacology; D019696:Peptidylprolyl Isomerase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D010641:Phenotype; D010766:Phosphorylation; D010940:Plant Proteins / Q000737:chemistry*; D010944:Plants / Q000201:enzymology*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D013696:Temperature; D013997:Time Factors; D019076:Transgenes
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D004791:Enzyme Inhibitors; D000072340:NIMA-Interacting Peptidylprolyl Isomerase; D009285:Naphthoquinones; C000606847:PIN1AT protein, Arabidopsis; D010940:Plant Proteins; D029701:Saccharomyces cerevisiae Proteins; D012313:RNA; C427747:Pin1 protein, Malus domestica; C000606845:ESS1 protein, S cerevisiae; C000606846:PIN1 protein, human; D019696:Peptidylprolyl Isomerase; C005134:juglone