MAP kinase-interacting kinase-2 (Mnk2) is one of the downstream kinasesactivated by MAP kinases. It phosphorylates the eukaryotic initiation factor 4E (elF4E), althoughthe role of elF4E phosphorylation and the role of...MAP kinase-interacting kinase-2 (Mnk2) is one of the downstream kinasesactivated by MAP kinases. It phosphorylates the eukaryotic initiation factor 4E (elF4E), althoughthe role of elF4E phosphorylation and the role of Mnk2 in the process of proteintranslation are notwell understood. Except for elF4E, other physiological substrates of Mnk2 are still unidentified. Tolook for these unidentified substrates and to reveal the physiological function of Mnk2, weperformed a yeast two-hybrid screening with Mnk2 as the bait. The results demonstrated Mnk2 couldinteract with VHL (von Hippel-Lindau tumor suppressor), Rbx1 (ring-box1) and Cul2 (Cullin2) proteinsin yeast cells. Furthermore, we validated the interaction between Mnk2 and VHL proteins inmammalian cells by co-immunoprecipitation analysis. Because the three proteins VHL, Rbx1 and Cul2are all components of the CBC^(VHL) ubiquitin ligase E3 complex, it has been shown that Mnk2 caninteract with CBC^(VHL) complex, and is probably one of the newsubstrates of the CBC^(VHL) complex.Furthermore, during the interaction of Mnk2 with von Hippel-Lindau (VHL) tumor suppressor- bindingprotein 1 (VBP1), it appears that Mnk2 also joins to modulate cell shape as VBP1 plays an importantrole in the process of the maturation of the cytoskeleton and in the process of morphogenesis.展开更多
文摘MAP kinase-interacting kinase-2 (Mnk2) is one of the downstream kinasesactivated by MAP kinases. It phosphorylates the eukaryotic initiation factor 4E (elF4E), althoughthe role of elF4E phosphorylation and the role of Mnk2 in the process of proteintranslation are notwell understood. Except for elF4E, other physiological substrates of Mnk2 are still unidentified. Tolook for these unidentified substrates and to reveal the physiological function of Mnk2, weperformed a yeast two-hybrid screening with Mnk2 as the bait. The results demonstrated Mnk2 couldinteract with VHL (von Hippel-Lindau tumor suppressor), Rbx1 (ring-box1) and Cul2 (Cullin2) proteinsin yeast cells. Furthermore, we validated the interaction between Mnk2 and VHL proteins inmammalian cells by co-immunoprecipitation analysis. Because the three proteins VHL, Rbx1 and Cul2are all components of the CBC^(VHL) ubiquitin ligase E3 complex, it has been shown that Mnk2 caninteract with CBC^(VHL) complex, and is probably one of the newsubstrates of the CBC^(VHL) complex.Furthermore, during the interaction of Mnk2 with von Hippel-Lindau (VHL) tumor suppressor- bindingprotein 1 (VBP1), it appears that Mnk2 also joins to modulate cell shape as VBP1 plays an importantrole in the process of the maturation of the cytoskeleton and in the process of morphogenesis.