Structure and Backbone Dynamics of Vanadate-Bound PRL-3: Comparison of 15N Nuclear Magnetic Resonance Relaxation Profiles of Free and Vanadate-Bound PRL-3
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- 作者：Ki-Woong Jeong ; Dong-Il Kang ; Eunjung Lee ; Areum Shin ; Bonghwan Jin ; Young-Guen Park ; Chung-Kyoung Lee ; Eun-Hee Kim ; Young Ho Jeon ; Eunice Eunkyeong Kim ; Yangmee Kim
- 刊名：Biochemistry
- 出版年：2014
- 出版时间：July 29, 2014
- 年：2014
- 卷：53
- 期：29
- 页码：4814-4825
- 全文大小：601K
- ISSN：1520-4995
文摘
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 伪4鈭捨?, and the polybasic region. Compared to free PRL-3, vanadate-bound PRL-3 has a longer 伪4 helix, where the catalytic R110 residue coordinates with vanadate in the active site. In addition, the hydrophobic cavity formed by helices 伪4鈭捨? with a depth of 14鈥?5 脜 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 kclose of 7 s鈥?. This intrinsic loop flexibility of PRL-3 may be related to their catalytic rate and may play a role in substrate recognition.