ID 58585
Author
Takabatake, Shota Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University
Fukumoto, Yusei Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University
Ohtsuka, Satomi Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University
Kanayama, Naoki Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University ORCID Kaken ID
Magari, Masaki Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University
Sakagami, Hiroyuki Department of Anatomy, Kitasato University School of Medicine
Hatano, Naoya Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University
Tokumitsu, Hiroshi pplied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University ORCID Kaken ID publons researchmap
Abstract
Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ) acts as a regulatory kinase that phosphorylates and activates multiple downstream kinases including CaMKI, CaMKIV, 5′AMP-activated protein kinase (AMPK) and protein kinase B (PKB), resulting in regulation of wide variety of Ca2+-dependent physiological responses under normal and pathological conditions. CaMKKβ is regulated by Ca2+/calmodulin-binding, autophosphorylation, and transphosphorylation by multiple protein kinases including cAMP-dependent protein kinase (PKA). In this report, we found that phosphorylation of CaMKKβ is dynamically regulated by protein phosphatase/kinase system in HeLa cells. Global phosphoproteomic analysis revealed the constitutive phosphorylation at 8 Ser residues including Ser128, 132, and 136 in the N-terminal regulatory domain of rat CaMKKβ in unstimulated HeLa cells as well as inducible phosphorylation of Thr144 in the cells treated with a phosphatase inhibitor, okadaic acid (OA). Thr144 phosphorylation in CaMKKβ has shown to be rapidly induced by OA treatment in a time- and dose-dependent manner in transfected HeLa cells, indicating that Thr144 in CaMKKβ is maintained unphosphorylated state by protein phosphatase(s). We confirmed that in vitro dephosphorylation of pThr144 in CaMKKβ by protein phosphatase 2A and 1. We also found that the pharmacological inhibition of protein phosphatase(s) significantly induces CaMKKβ-phosphorylating activity (at Thr144) in HeLa cell lysates as well as in intact cells; however, it was unlikely that this activity was catalyzed by previously identified Thr144-kinases, such as AMPK and PKA. Taken together, these results suggest that the phosphorylation and dephosphorylation of Thr144 in CaMKKβ is dynamically regulated by multiple kinases/phosphatases signaling resulting in fine-tuning of the enzymatic property.
Keywords
CaMKKβ
Phosphorylation
Dephosphorylation
PP1
PP2A
Okadaic acid
Note
This fulltext is available in Feb. 2021.
Published Date
2020-04-23
Publication Title
Biochemical and Biophysical Research Communications
Volume
volume525
Issue
issue1
Publisher
Academic Press
Start Page
251
End Page
257
ISSN
0006-291X
NCID
AA00564395
Content Type
Journal Article
language
英語
OAI-PMH Set
岡山大学
File Version
author
PubMed ID
DOI
Web of Science KeyUT
Related Url
isVersionOf https://doi.org/10.1016/j.bbrc.2020.02.056
Funder Name
Ministry of Education, Culture, Sports, Science and Technology
助成番号
JP18K06113
JP18K02255