|
||
Article |
CaM kinase I
–induced phosphorylation of Drp1 regulates mitochondrial morphology
Correspondence to Masayuki Matsushita: masayuki{at}mitils.jp
Mitochondria are dynamic organelles that frequently move, divide, and fuse with one another to maintain their architecture and functions. However, the signaling mechanisms involved in these processes are still not well characterized. In this study, we analyze mitochondrial dynamics and morphology in neurons. Using time-lapse imaging, we find that Ca2+ influx through voltage-dependent Ca2+ channels (VDCCs) causes a rapid halt in mitochondrial movement and induces mitochondrial fission. VDCC-associated Ca2+ signaling stimulates phosphorylation of dynamin-related protein 1 (Drp1) at serine 600 via activation of Ca2+/calmodulin-dependent protein kinase I
(CaMKI
). In neurons and HeLa cells, phosphorylation of Drp1 at serine 600 is associated with an increase in Drp1 translocation to mitochondria, whereas in vitro, phosphorylation of Drp1 results in an increase in its affinity for Fis1. CaMKI
is a widely expressed protein kinase, suggesting that Ca2+ is likely to be functionally important in the control of mitochondrial dynamics through regulation of Drp1 phosphorylation in neurons and other cell types.
-CA, constitutively active CaMKI
; CaMKI
-DN, dominant-negative CaMKI
; DIV, days in vitro; Drp1, dynamin-related protein 1; GED, GTPase effector domain; VDCC, voltage-dependent Ca2+ channel. © 2008 Han et al. This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.jcb.org/misc/terms.shtml). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 3.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/3.0/).
Related In this Issue article
This article has been cited by other articles:
|
|