PKC Regulation of Microfilament Network Organization in Keratinocytes Defined by a Pharmacological Study with PKC Activators and Inhibitors

Masson-Gadais, Bénédicte; Salers, P.; Bongrand, Pierre; Lissitzky, Jean‐Claude

doi:10.1006/excr.1997.3721

Cited by 30 publications

(20 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is not known which isotype of PKC is involved in the PKC-dependent migration, because GF109203X at the concentration used in the present study (5 M) attenuates the PKC activation of various subfamilies found in keratinocytes (24,25). Activation of PKC has been reported to play an important role in keratinocyte migration through enhancement of the specific integrin-mediated mo- tility (26), microfilament organization (27), or up-regulation of proteinases such as metalloproteinases (28) and urokinase (29). Requirement of PI3K activation for the Stat3-independent PKC-dependent signaling pathway toward migration was clearly demonstrated by in vitro studies by using wortmannin, a specific inhibitor of PI3K (Fig.…”

Section: Discussionmentioning

confidence: 85%

Two distinct signaling pathways in hair cycle induction: Stat3-dependent and -independent pathways

Sano

Kira

Takagi

et al. 2000

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The hair follicle is an epidermal derivative that undergoes cycles of growth, involution, and rest. The hair cycle has well-orchestrated kinetics regulated by interactions between mesenchymal and epithelial cells, although the intracellular signals remain unclear. We previously established keratinocyte-specific Stat3-disrupted mice, by which we demonstrated that signal transducer and activator of transcription 3 (Stat3) is required for wound healing and anagen progression in the hair cycle. Growth factor-dependent migration of Stat3-disrupted keratinocytes was severely impaired, suggesting that not only wound healing but also telogen-to-anagen progression required organized keratinocyte migration in response to mesenchymal stimuli. In the present study, to examine whether Stat3 activation in keratinocytes is a prerequisite for hair cycle progression, we applied methods for experimental anagen induction to Stat3-disrupted mice. It was demonstrated that anagen was successfully induced in Stat3-disrupted as well as wild-type mice by chemical or mechanical stimulation, i.e., by topical application of phorbol 12-myristate 13-acetate (PMA) or by hair plucking, respectively. This result indicated that anagen in these methods occurred in the absence of Stat3. Furthermore, PMA stimulated the migration of Stat3-disrupted keratinocytes in vitro , supporting a hypothesis that the protein kinase C (PKC) and Stat3 pathways occur independently in the postnatal anagen induction. Both Stat3-dependent and -independent migration of keratinocytes was inhibited by a phosphoinositide 3-kinase (PI3K) inhibitor, wortmannin. Therefore, we infer that entry into anagen is mediated by at least two distinct signaling pathways: Stat3-dependent pathway for spontaneous hair cycling and Stat3-independent (probably PKC-dependent) pathway for exogenously induced hair cycling, whereas both pathways require PI3K activation.

show abstract

Section: Discussionmentioning

confidence: 85%

Two distinct signaling pathways in hair cycle induction: Stat3-dependent and -independent pathways

Sano

Kira

Takagi

et al. 2000

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Microfilament organization of RF/6A cells was assessed by a modification of the immunofluorescence analysis protocol with rhodamine-phalloidin as described elsewhere [19] . After transfection, cells were trypsinized and seeded onto coverslips for 6 h at 37 ° C in 5% CO 2 .…”

Section: Immunofluorescence Analysis Of Microfilamentsmentioning

confidence: 99%

Targeting of Integrin-Linked Kinase with a Small Interfering RNA Inhibits Endothelial Cell Migration, Proliferation and Tube Formation in vitro

Guo

Yu²,

Li³

et al. 2009

Ophthalmic Res

View full text Add to dashboard Cite

Purpose: To investigate the role of integrin-linked kinase (ILK) in endothelial cell migration, proliferation and tube formation in vitro. Materials and Methods: Cultured RF/6A cells were knocked down for ILK using small interfering RNA (siRNA). Cellular ILK expression was quantified by real-time quantitative PCR and Western blot analysis. Cell migration was measured by cell counting in modified Boyden chambers, while microfilament dynamics were assessed by immunofluorescence analysis. Cell cycling was determined using a FACS Calibur flow cytometer, and the expression of cyclin D₁ was also measured by the Western blot assay. The secretion of vascular endothelial growth factor (VEGF) in culture medium samples was assessed by ELISA, and capillary/tube-like network formation assays were performed using matrigel. Results: Both ILK mRNA and protein levels were vir- tually undetectable after transfection with ILK siRNA. In addition, there was a significant accumulation of cells in the G₀–G₁ phase and a marked decrease in cell numbers in the S phase in ILK-specific siRNA-transfected cells, and the expression of cyclin D₁ was decreased after transfection. The knockdown of ILK significantly inhibited cell migration ability by disturbing F actin assembly, and VEGF secretion in conditioned medium was also reduced by 33%. Furthermore, treatment with ILK siRNA suppressed tube formation in RF/6A cells and significantly reduced the overall length of the tubes. Conclusions: Knockdown of ILK with siRNA effectively inhibits endothelial cell migration, proliferation and tube formation in vitro.

show abstract

“…Protein kinase C isoforms are another group of signaling molecules that may be relevant with respect to ALCAMmediated adhesion. They were shown to significantly contribute to cytoskeletal rearrangements (Masson-Gadais et al, 1997;Keenan and Kelleher, 1998) and even bind filamentous actin (Slater et al, 2000). In locomotory T cells, PKCβ is involved in LFA-1-mediated signaling and cytoskeletal scaffolding (Altman and Villalba, 2002).…”

mentioning

confidence: 99%

Cytoskeletal restraints regulate homotypic ALCAM-mediated adhesion through PKCα independently of Rho-like GTPases

Zimmerman

Nelissen

Vries³

et al. 2004

Journal of Cell Science

View full text Add to dashboard Cite

The activated leukocyte cell adhesion molecule (ALCAM) is dynamically regulated by the actin cytoskeleton. In this study we explored the molecular mechanisms and signaling pathways underlying the cytoskeletal restraints of this homotypic adhesion molecule. We observed that ALCAM-mediated adhesion induced by cytoskeleton-disrupting agents is accompanied by activation of the small GTPases RhoA, Rac1 and Cdc42. Interestingly, unlike adhesion mediated by integrins or cadherins, ALCAM-mediated adhesion appears to be independent of Rho-like GTPase activity. By contrast, we demonstrated that protein kinase C (PKC) plays a major role in ALCAM-mediated adhesion. PKC inhibition by chelerythrine chloride and myristoylated PKC pseudosubstrate, as well as PKC downregulation by PMA strongly reduce cytoskeleton-dependent ALCAM-mediated adhesion. Since serine and threonine residues are dispensable for ALCAM-mediated adhesion and ALCAM is not phosphorylated, we can rule out that ALCAM itself is a direct PKC substrate. We conclude that PKCα plays a dominant role in cytoskeleton-dependent avidity modulation of ALCAM.

show abstract

PKC Regulation of Microfilament Network Organization in Keratinocytes Defined by a Pharmacological Study with PKC Activators and Inhibitors

Cited by 30 publications

References 48 publications

Two distinct signaling pathways in hair cycle induction: Stat3-dependent and -independent pathways

Two distinct signaling pathways in hair cycle induction: Stat3-dependent and -independent pathways

Targeting of Integrin-Linked Kinase with a Small Interfering RNA Inhibits Endothelial Cell Migration, Proliferation and Tube Formation in vitro

Cytoskeletal restraints regulate homotypic ALCAM-mediated adhesion through PKCα independently of Rho-like GTPases

Contact Info

Product

Resources

About