PUBLICATION
Autoactivation of C-terminally truncated Ca2+/calmodulin-dependent protein kinase (CaMK) Iδ via CaMK kinase-independent autophosphorylation
- Authors
- Akizuki, K., Kinumi, T., Ono, A., Senga, Y., Osawa, J., Shigeri, Y., Ishida, A., Kameshita, I., Sueyoshi, N.
- ID
- ZDB-PUB-190510-15
- Date
- 2019
- Source
- Archives of biochemistry and biophysics 668: 29-38 (Journal)
- Registered Authors
- Keywords
- Autoactivation, CaMKI, Isozyme, Phosphorylation mimic, Truncation, λPPase
- MeSH Terms
-
- Amino Acid Sequence
- Isoenzymes/chemistry
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Escherichia coli/enzymology
- Rats
- Mutagenesis, Site-Directed
- Protein Processing, Post-Translational
- Enzyme Activation/physiology*
- Mutation
- Zebrafish Proteins/chemistry
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism*
- Animals
- Mice, Inbred BALB C
- Calcium-Calmodulin-Dependent Protein Kinase Type 1/chemistry
- Calcium-Calmodulin-Dependent Protein Kinase Type 1/genetics
- Calcium-Calmodulin-Dependent Protein Kinase Type 1/metabolism*
- Phosphorylation
- Sequence Alignment
- Zebrafish
- Calcium-Calmodulin-Dependent Protein Kinase Kinase/metabolism*
- Serine/chemistry
- PubMed
- 31071303 Full text @ Arch. Biochem. Biophys.
Citation
Akizuki, K., Kinumi, T., Ono, A., Senga, Y., Osawa, J., Shigeri, Y., Ishida, A., Kameshita, I., Sueyoshi, N. (2019) Autoactivation of C-terminally truncated Ca2+/calmodulin-dependent protein kinase (CaMK) Iδ via CaMK kinase-independent autophosphorylation. Archives of biochemistry and biophysics. 668:29-38.
Abstract
Ca2+/calmodulin-dependent protein kinase I isoforms (CaMKIα, β, γ, and δ) play important roles in Ca2+ signaling in eukaryotic cells by being activated by CaMK kinase (CaMKK) through phosphorylation at a Thr residue in the activation loop. However, we have recently found that, unlike rat CaMKIα (rCaMKIα), C-terminally truncated fragments of zebrafish and mouse CaMKIδ [zCaMKIδ(1-299) and mCaMKIδ(1-297)] produced by Escherichia coli exhibit almost full activity in the absence of CaMKK. To address the CaMKK-independent activation mechanism of CaMKIδ in E. coli cells, here we performed comparative analyses between recombinant zCaMKIδ(1-299) and rCaMKIα(1-294) in vitro. By using a kinase-dead mutant of zCaMKIδ(1-299) and λ phosphatase coexpression method, we elucidated that zCaMKIδ(1-299) was highly autophosphorylated and activated in E. coli during cell culture, but rCaMKIα(1-294) was not. The major autophosphorylation site leading to activation of the kinase was Ser296, determined using mass spectrometry analysis in conjunction with site-directed mutagenesis. Furthermore, mimicking phosphorylation at Ser296 in full-length zCaMKIδ resulted in additional activation of the kinase compared with CaMKI fully activated by CaMKK. Our results provide the first evidence that CaMKIδ is activated through CaMKK-independent phosphorylation at Ser296, which might be a clue to understand the physiological regulation of CaMKIδ isoform.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping