Deficiency of the 15-kDa selenoprotein led to cytoskeleton remodeling and non-apoptotic membrane blebbing through a RhoA/ROCK pathway

Jeyoung Bang; Mihyun Jang; Jang Hoe Huh; Ji-Woon Na; Myoungsup Shim; Bradley A Carlson; Ryuta Tobe; Petra A Tsuji; Vadim N Gladyshev; Dolph L Hatfield; Byeong Jae Lee

doi:10.1016/j.bbrc.2014.12.059

Deficiency of the 15-kDa selenoprotein led to cytoskeleton remodeling and non-apoptotic membrane blebbing through a RhoA/ROCK pathway

Biochem Biophys Res Commun. 2015 Jan 24;456(4):884-90. doi: 10.1016/j.bbrc.2014.12.059. Epub 2014 Dec 18.

Authors

Affiliations

¹ School of Biological Sciences, Seoul National University, Seoul 151-742, Republic of Korea; Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul 151-742, Republic of Korea.
² School of Biological Sciences, Seoul National University, Seoul 151-742, Republic of Korea.
³ School of Biological Sciences, Seoul National University, Seoul 151-742, Republic of Korea; Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Republic of Korea.
⁴ Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
⁵ Department of Biological Sciences, Towson University, Towson, MD 21252, USA.
⁶ Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
⁷ School of Biological Sciences, Seoul National University, Seoul 151-742, Republic of Korea; Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul 151-742, Republic of Korea; Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Republic of Korea. Electronic address: imbglmg@snu.ac.kr.

Abstract

The 15-kDa selenoprotein (Sep15) has been implicated in etiology of some types of cancer. Herein, inducible RNAi cell lines were established and cell morphology and motility were analyzed. The majority of Sep15-deficient cells (>95%) formed membrane blebs in a dynamic manner. Blebbing cells transformed cell morphology from a normal flat spindle shape to a spherical morphology. In blebbing cells, actin fibers moved to the cell periphery, covering and obscuring visualization of α-tubulin. Bleb formation was suppressed by the inhibitors of Rho-associated protein kinase (ROCK), RhoA or myosin light chain (MLC), restoring blebbing cells to wild-type morphology. RhoA activation and phosphorylation of myosin phosphatase target subunit 1 was induced by Sep15 knockdown. Sep15-deficient cells were non-apoptotic, and displayed a distinct relative localization of F-actin and α-tubulin from typical apoptotic blebbing cells. Our data suggest that Sep15 in Chang liver cells regulates the pathway that antagonizes RhoA/ROCK/MLC-dependent non-apoptotic bleb formation.

Keywords: 15-kDa selenoprotein; Apoptosis; Cytoskeletal protein; Membrane blebbing; Selenium.

Publication types

Research Support, N.I.H., Intramural
Research Support, Non-U.S. Gov't

MeSH terms

Amides / pharmacology
Apoptosis* / drug effects
Cell Line, Tumor
Cell Membrane Structures / drug effects
Cell Membrane Structures / metabolism*
Cytoskeleton / drug effects
Cytoskeleton / metabolism*
Gene Knockdown Techniques
Humans
Myosin-Light-Chain Kinase / antagonists & inhibitors
Pyridines / pharmacology
Selenoproteins / deficiency*
Selenoproteins / metabolism
Signal Transduction* / drug effects
rho-Associated Kinases / metabolism*
rhoA GTP-Binding Protein / metabolism*

Substances

Amides
Pyridines
SELENOF protein, human
Selenoproteins
Y 27632
rho-Associated Kinases
Myosin-Light-Chain Kinase
rhoA GTP-Binding Protein

Abstract

Publication types

MeSH terms

Substances

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