title: Structure and backbone dynamics of vanadate-bound PRL-3: comparison of 15N nuclear magnetic resonance relaxation profiles of free and vanadate-bound PRL-3.
abstract: Phosphatases of regenerating liver (PRLs) constitute a novel class of small, prenylated phosphatases with oncogenic activity. PRL-3 is particularly important in cancer metastasis and represents a potential therapeutic target. The flexibility of the WPD loop as well as the P-loop of protein tyrosine phosphatases is closely related to their catalytic activity. Using nuclear magnetic resonance spectroscopy, we studied the structure of vanadate-bound PRL-3, which was generated by addition of sodium orthovanadate to PRL-3. The WPD loop of free PRL-3 extended outside of the active site, forming an open conformation, whereas that of vanadate-bound PRL-3 was directed into the active site by a large movement, resulting in a closed conformation. We suggest that vanadate binding induced structural changes in the WPD loop, P-loop, helices α4-α6, and the polybasic region. Compared to free PRL-3, vanadate-bound PRL-3 has a longer α4 helix, where the catalytic R110 residue coordinates with vanadate in the active site. In addition, the hydrophobic cavity formed by helices α4-α6 with a depth of 14-15 Å can accommodate a farnesyl chain at the truncated prenylation motif of PRL-3, i.e., from R169 to M173. Conformational exchange data suggested that the WPD loop moves between open and closed conformations with a closing rate constant k(close) of 7 s(-1). This intrinsic loop flexibility of PRL-3 may be related to their catalytic rate and may play a role in substrate recognition.
authors.affiliation: Department of Bioscience and Biotechnology and BioMolecular Informatics Center, Konkuk University , Seoul 143-701, South Korea.
authors.forename: Ki-Woong
authors.initials: KW
authors.lastname: Jeong
authors.forename: Dong-Il
authors.initials: DI
authors.lastname: Kang
authors.forename: Eunjung
authors.initials: E
authors.lastname: Lee
authors.forename: Areum
authors.initials: A
authors.lastname: Shin
authors.forename: Bonghwan
authors.initials: B
authors.lastname: Jin
authors.forename: Young-Guen
authors.initials: YG
authors.lastname: Park
authors.forename: Chung-Kyoung
authors.initials: CK
authors.lastname: Lee
authors.forename: Eun-Hee
authors.initials: EH
authors.lastname: Kim
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Jeon
authors.forename: Eunice Eunkyeong
authors.initials: EE
authors.lastname: Kim
authors.forename: Yangmee
authors.initials: Y
authors.lastname: Kim
mesh_terms: D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors / Q000737:chemistry*; D014638:Vanadates / Q000737:chemistry*
chemical_list: D009363:Neoplasm Proteins; D014638:Vanadates; C484730:PTP4A3 protein, human; D017027:Protein Tyrosine Phosphatases