Park Hyunju, Ahn Keun Jae, Lee Kang Jihee, Choi Youn-Hee
Department of Physiology, Tissue Injury Defense Research Center, Ewha Womans University School of Medicine, Seoul 158-710, Korea.
Department of Science Education, Jeju National University, Jeju 690-756, Korea.
BMB Rep. 2015 Mar;48(3):184-9. doi: 10.5483/bmbrep.2015.48.3.249.
Src homology 2-containing protein tyrosine phosphatase 2 (SHP-2) is known to protect neurons from neurodegeneration during ischemia/reperfusion injury. We recently reported that ROS-mediated oxidative stress promotes phosphorylation of endogenous SHP-2 in astrocytes and complex formation between caveolin-1 and SHP-2 in response to oxidative stress. To examine the region of SHP-2 participating in complex formation with caveolin-1, we generated three deletion mutant constructs and six point mutation constructs of SHP-2. Compared with wild-type SHP-2, binding of the N-SH2 domain deletion mutant of SHP-2 to p-caveolin-1 was reduced greatly, using flow cytometric competitive binding assays and surface plasmon resonance (SPR). Moreover, deletion of the N-SH2 domain of SHP-2 affected H2O2-mediated ERK phosphorylation and Src phosphorylation at Tyr 419 in primary astrocytes, suggesting that N-SH2 domain of SHP-2 is responsible for the binding of caveolin-1 and contributes to the regulation of Src phosphorylation and activation following ROS-induced oxidative stress in brain astrocytes.
含Src同源2结构域的蛋白酪氨酸磷酸酶2(SHP - 2)已知可在缺血/再灌注损伤期间保护神经元免受神经退行性变。我们最近报道,ROS介导的氧化应激促进星形胶质细胞内源性SHP - 2的磷酸化以及在氧化应激反应中窖蛋白 - 1与SHP - 2之间形成复合物。为了研究SHP - 2中参与与窖蛋白 - 1形成复合物的区域,我们构建了三个SHP - 2缺失突变体构建体和六个点突变构建体。使用流式细胞术竞争结合测定和表面等离子体共振(SPR),与野生型SHP - 2相比,SHP - 2的N - SH2结构域缺失突变体与磷酸化窖蛋白 - 1的结合大大减少。此外,SHP - 2的N - SH2结构域缺失影响原代星形胶质细胞中H2O2介导的ERK磷酸化和Tyr 419处的Src磷酸化,表明SHP - 2的N - SH2结构域负责窖蛋白 - 1的结合,并有助于在脑星形胶质细胞中ROS诱导的氧化应激后调节Src磷酸化和激活。