Saltar al contenido
Merck
  • Apigenin inhibition of involucrin gene expression is associated with a specific reduction in phosphorylation of protein kinase Cdelta Tyr311.

Apigenin inhibition of involucrin gene expression is associated with a specific reduction in phosphorylation of protein kinase Cdelta Tyr311.

The Journal of biological chemistry (2006-09-20)
Sivaprakasam Balasubramanian, Ling Zhu, Richard L Eckert
RESUMEN

Apigenin is a plant-derived flavanoid that has significant promise as a skin cancer chemopreventive agent. In the present study, we examine the mechanism whereby apigenin regulates normal human keratinocyte differentiation. Expression of involucrin (hINV), a marker of keratinocyte differentiation, is increased by differentiating agents via a protein kinase Cdelta (PKCdelta), Ras, MEKK1, MEK3 cascade that increases AP1 factor level and AP1 factor binding to DNA elements in the hINV promoter. We show that apigenin inhibits this response. Apigenin suppresses the 12-O-tetradeconylphorbol-13-acetate-dependent increase in AP1 factor expression and binding to the hINV promoter and the increase in hINV promoter activity. Apigenin also inhibits the increase in promoter activity observed following overexpression of PKCdelta, constitutively active Ras, or MEKK1. The suppression of PKCdelta activity is associated with reduced phosphorylation of PKCdelta-Y311. The physiological importance of this phosphorylation event was confirmed by showing that the PKCdelta phosphorylation-defective mutant, PKCdelta-Y311F, is less able to increase hINV promoter activity. Activation of hINV promoter activity by the green tea polyphenol, (-)-epigellocathecin-3-gallate, is also inhibited by apigenin, suggesting that the two chemopreventive agents can produce opposing actions in keratinocytes. Additional studies show that the apigenin-dependent suppression of differentiation is associated with reduced cell proliferation but that there is no evidence of apoptosis.

MATERIALES
Referencia del producto
Marca
Descripción del producto

Sigma-Aldrich
Anti-β-actina monoclonal antibody produced in mouse, clone AC-15, ascites fluid
Número de referencia del producto (SKU)
Tamaño de envase
Disponibilidad
Precio
Cantidad
Sigma-Aldrich
Apigenin, ≥95.0% (HPLC)
Número de referencia del producto (SKU)
Tamaño de envase
Disponibilidad
Precio
Cantidad
Sigma-Aldrich
Anti-MAP Kinase (ERK-1, ERK-2) antibody produced in rabbit, whole antiserum
Número de referencia del producto (SKU)
Tamaño de envase
Disponibilidad
Precio
Cantidad
Sigma-Aldrich
Anti-p38 MAP Kinase, Activated (Diphosphorylated p38) antibody, Mouse monoclonal, clone P38-TY, purified from hybridoma cell culture, buffered aqueous solution
Número de referencia del producto (SKU)
Tamaño de envase
Disponibilidad
Precio
Cantidad
Supelco
Apigenin, analytical standard
Número de referencia del producto (SKU)
Tamaño de envase
Disponibilidad
Precio
Cantidad