Cloning and characterization of microbial activated Aedes aegypti MEK4 (AaMEK4): influences of noncatalytic domains on enzymatic activity
Autor(es): Wu, R. C-C.; Cho, W-L.
Resumo: Protein kinases are known to be involved in a number of signal transduction cascades. Both the stress-activated Jun N-terminal kinase (JNK) and mitogen-activated protein kinase (MAPK) p38 pathways have been shown to correlate with the insect immune response to microbial infection. MAP kinase kinase 4 (MEK4) is an upstream kinase of JNK and p38 kinase. The cDNA of AaMEK4 was cloned and characterized. AaMEK4 was activated by microbial lysates of Gram-positive, Gram-negative bacteria and yeast. The conserved lysine (K-112) and the putative phosphorylation sites (S-238 and T-242) were shown to be important for kinase activity by site-directed mutagenesis. A common MAPK docking site (MAPK_dsA) was found and in addition, a new nearby docking site, MAPK_dsB, was identified in the N-terminal noncatalytic domain of AaMEK4. MAPK_dsB was shown to be a unique element in the MEK4 family. In this study, both MAPK_dsA and _dsB were demonstrated to be important to AaMEK4 enzymatic activity for the downstream protein kinase, Aap38.
Palavras-Chave: Aedes aegypti; Protein kinase; Innate immunity; Signal transduction; MAPK docking site
Imprenta: Insect Molecular Biology, v. 23, n. 5, p. 644-655, 2014
Identificador do objeto digital: 10.1111/imb.12116
Descritores: Aedes aegypti - DNA ; Aedes aegypti - Immune response ; Aedes aegypti - Molecular structure ; Aedes aegypti - Proteins
Data de publicação: 2014
