Choi Insup, Byun Ji-Won, Park Sang Myun, Jou Ilo, Joe Eun-Hye
Department of Biomedical Sciences, Neuroscience Graduate Program, Ajou University School of Medicine, Suwon 16499, Korea.; Department of Pharmacology, Ajou University School of Medicine, Suwon 16499, Korea.; Department of Brain Science, Ajou University School of Medicine, Suwon 16499, Korea.; Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon 16499, Korea.
Department of Biomedical Sciences, Neuroscience Graduate Program, Ajou University School of Medicine, Suwon 16499, Korea.
Exp Neurobiol. 2016 Oct;25(5):269-276. doi: 10.5607/en.2016.25.5.269. Epub 2016 Oct 26.
Mutation of leucine-rich repeat kinase 2 (LRRK2) causes an autosomal dominant and late-onset familial Parkinson's disease (PD). Recently, we reported that LRRK2 directly binds to and phosphorylates the threonine 474 (T474)-containing Thr-X-Arg(Lys) (TXR) motif of focal adhesion kinase (FAK), thereby inhibiting the phosphorylation of FAK at tyrosine (Y) 397 residue (pY397-FAK), which is a marker of its activation. Mechanistically, however, it remained unclear how T474-FAK phosphorylation suppressed FAK activation. Here, we report that T474-FAK phosphorylation could inhibit FAK activation via at least two different mechanisms. First, T474 phosphorylation appears to induce a conformational change of FAK, enabling its N-terminal FERM domain to autoinhibit Y397 phosphorylation. This is supported by the observation that the levels of pY397-FAK were increased by deletion of the FERM domain and/or mutation of the FERM domain to prevent its interaction with the kinase domain of FAK. Second, pT474-FAK appears to recruit SHP-2, which is a phosphatase responsible for dephosphorylating pY397-FAK. We found that mutation of T474 into glutamate (T474E-FAK) to mimic phosphorylation induced more strong interaction with SHP-2 than WT-FAK, and that pharmacological inhibition of SHP-2 with NSC-87877 rescued the level of pY397 in HEK293T cells. These results collectively show that LRRK2 suppresses FAK activation through diverse mechanisms that include the promotion of autoinhibition and/or the recruitment of phosphatases, such as SHP-2.
富含亮氨酸重复激酶2(LRRK2)的突变会导致常染色体显性和迟发性家族性帕金森病(PD)。最近,我们报道LRRK2直接结合并磷酸化粘着斑激酶(FAK)中含苏氨酸474(T474)的苏氨酸- X - 精氨酸(赖氨酸)(TXR)基序,从而抑制FAK在酪氨酸(Y)397残基处的磷酸化(pY397-FAK),pY397-FAK是其激活的标志物。然而,从机制上来说,T474-FAK磷酸化如何抑制FAK激活仍不清楚。在此,我们报道T474-FAK磷酸化可通过至少两种不同机制抑制FAK激活。首先,T474磷酸化似乎会诱导FAK的构象变化,使其N端的FERM结构域能够自动抑制Y397磷酸化。FERM结构域缺失和/或FERM结构域发生突变以阻止其与FAK激酶结构域相互作用时,pY397-FAK水平升高,这一观察结果支持了这一点。其次,pT474-FAK似乎会募集SHP-2,SHP-2是一种负责使pY397-FAK去磷酸化的磷酸酶。我们发现将T474突变为谷氨酸(T474E-FAK)以模拟磷酸化会比野生型FAK诱导更强的与SHP-2的相互作用,并且用NSC-87877对SHP-2进行药理学抑制可挽救HEK293T细胞中pY397的水平。这些结果共同表明,LRRK2通过多种机制抑制FAK激活,这些机制包括促进自动抑制和/或募集磷酸酶,如SHP-2。