Limits...
Spatial and temporal regulation of cofilin activity by LIM kinase and Slingshot is critical for directional cell migration.

Nishita M, Tomizawa C, Yamamoto M, Horita Y, Ohashi K, Mizuno K - J. Cell Biol. (2005)

Bottom Line: Cofilin is inactivated by LIM kinase (LIMK)-1-mediated phosphorylation and is reactivated by cofilin phosphatase Slingshot (SSH)-1L.In this study, we show that cofilin activity is temporally and spatially regulated by LIMK1 and SSH1L in chemokine-stimulated Jurkat T cells.We propose that LIMK1- and SSH1L-mediated spatiotemporal regulation of cofilin activity is critical for chemokine-induced polarized lamellipodium formation and directional cell movement.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomolecular Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan.

ABSTRACT
Cofilin mediates lamellipodium extension and polarized cell migration by accelerating actin filament dynamics at the leading edge of migrating cells. Cofilin is inactivated by LIM kinase (LIMK)-1-mediated phosphorylation and is reactivated by cofilin phosphatase Slingshot (SSH)-1L. In this study, we show that cofilin activity is temporally and spatially regulated by LIMK1 and SSH1L in chemokine-stimulated Jurkat T cells. The knockdown of LIMK1 suppressed chemokine-induced lamellipodium formation and cell migration, whereas SSH1L knockdown produced and retained multiple lamellipodial protrusions around the cell after cell stimulation and impaired directional cell migration. Our results indicate that LIMK1 is required for cell migration by stimulating lamellipodium formation in the initial stages of cell response and that SSH1L is crucially involved in directional cell migration by restricting the membrane protrusion to one direction and locally stimulating cofilin activity in the lamellipodium in the front of the migrating cell. We propose that LIMK1- and SSH1L-mediated spatiotemporal regulation of cofilin activity is critical for chemokine-induced polarized lamellipodium formation and directional cell movement.

Show MeSH

Related in: MedlinePlus

Cofilin, but not P-cofilin, accumulates in the SDF-1α–induced lamellipodial membrane protrusion in Jurkat cells. Jurkat cells were left unstimulated (0 min) or were stimulated with 5 nM SDF-1α for the indicated periods of time. Cells were costained with anti–β-actin mAb (red) and anticofilin (A) or anti–P-cofilin (B) pAbs (green). Merged images are shown in the bottom panels. Bars, 5 μm.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2171197&req=5

fig3: Cofilin, but not P-cofilin, accumulates in the SDF-1α–induced lamellipodial membrane protrusion in Jurkat cells. Jurkat cells were left unstimulated (0 min) or were stimulated with 5 nM SDF-1α for the indicated periods of time. Cells were costained with anti–β-actin mAb (red) and anticofilin (A) or anti–P-cofilin (B) pAbs (green). Merged images are shown in the bottom panels. Bars, 5 μm.

Mentions: We next examined the temporal distribution of cofilin and P-cofilin in Jurkat cells before and after SDF-1α stimulation (Fig. 3). Cell staining with cofilin- or P-cofilin–specific antibodies and β-actin antibody revealed that cofilin, but not P-cofilin, accumulated in F-actin–rich membrane protrusions after SDF-1α stimulation. In unstimulated cells, both cofilin and P-cofilin diffusely distributed in the cytoplasm. These data indicate that the active (unphosphorylated) form of cofilin is preferentially concentrated in the lamellipodium after SDF-1α stimulation. Localization of cofilin, but not P-cofilin, in the lamellipodium was also noted in migrating fibroblasts and carcinoma cells (Dawe et al., 2003; Nagata-Ohashi et al., 2004). Because SSH1L is activated by associating with F-actin, these findings suggest that the SSH1L molecules recruited to the F-actin–rich lamellipodium are activated and may be involved in local dephosphorylation/activation of cofilin in this region.


Spatial and temporal regulation of cofilin activity by LIM kinase and Slingshot is critical for directional cell migration.

Nishita M, Tomizawa C, Yamamoto M, Horita Y, Ohashi K, Mizuno K - J. Cell Biol. (2005)

Cofilin, but not P-cofilin, accumulates in the SDF-1α–induced lamellipodial membrane protrusion in Jurkat cells. Jurkat cells were left unstimulated (0 min) or were stimulated with 5 nM SDF-1α for the indicated periods of time. Cells were costained with anti–β-actin mAb (red) and anticofilin (A) or anti–P-cofilin (B) pAbs (green). Merged images are shown in the bottom panels. Bars, 5 μm.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2171197&req=5

fig3: Cofilin, but not P-cofilin, accumulates in the SDF-1α–induced lamellipodial membrane protrusion in Jurkat cells. Jurkat cells were left unstimulated (0 min) or were stimulated with 5 nM SDF-1α for the indicated periods of time. Cells were costained with anti–β-actin mAb (red) and anticofilin (A) or anti–P-cofilin (B) pAbs (green). Merged images are shown in the bottom panels. Bars, 5 μm.
Mentions: We next examined the temporal distribution of cofilin and P-cofilin in Jurkat cells before and after SDF-1α stimulation (Fig. 3). Cell staining with cofilin- or P-cofilin–specific antibodies and β-actin antibody revealed that cofilin, but not P-cofilin, accumulated in F-actin–rich membrane protrusions after SDF-1α stimulation. In unstimulated cells, both cofilin and P-cofilin diffusely distributed in the cytoplasm. These data indicate that the active (unphosphorylated) form of cofilin is preferentially concentrated in the lamellipodium after SDF-1α stimulation. Localization of cofilin, but not P-cofilin, in the lamellipodium was also noted in migrating fibroblasts and carcinoma cells (Dawe et al., 2003; Nagata-Ohashi et al., 2004). Because SSH1L is activated by associating with F-actin, these findings suggest that the SSH1L molecules recruited to the F-actin–rich lamellipodium are activated and may be involved in local dephosphorylation/activation of cofilin in this region.

Bottom Line: Cofilin is inactivated by LIM kinase (LIMK)-1-mediated phosphorylation and is reactivated by cofilin phosphatase Slingshot (SSH)-1L.In this study, we show that cofilin activity is temporally and spatially regulated by LIMK1 and SSH1L in chemokine-stimulated Jurkat T cells.We propose that LIMK1- and SSH1L-mediated spatiotemporal regulation of cofilin activity is critical for chemokine-induced polarized lamellipodium formation and directional cell movement.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomolecular Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan.

ABSTRACT
Cofilin mediates lamellipodium extension and polarized cell migration by accelerating actin filament dynamics at the leading edge of migrating cells. Cofilin is inactivated by LIM kinase (LIMK)-1-mediated phosphorylation and is reactivated by cofilin phosphatase Slingshot (SSH)-1L. In this study, we show that cofilin activity is temporally and spatially regulated by LIMK1 and SSH1L in chemokine-stimulated Jurkat T cells. The knockdown of LIMK1 suppressed chemokine-induced lamellipodium formation and cell migration, whereas SSH1L knockdown produced and retained multiple lamellipodial protrusions around the cell after cell stimulation and impaired directional cell migration. Our results indicate that LIMK1 is required for cell migration by stimulating lamellipodium formation in the initial stages of cell response and that SSH1L is crucially involved in directional cell migration by restricting the membrane protrusion to one direction and locally stimulating cofilin activity in the lamellipodium in the front of the migrating cell. We propose that LIMK1- and SSH1L-mediated spatiotemporal regulation of cofilin activity is critical for chemokine-induced polarized lamellipodium formation and directional cell movement.

Show MeSH
Related in: MedlinePlus