Phosphorylation of Zona Occludens-2 by Protein Kinase C epsilon Regulates Its Nuclear Exportation
Por:
Chamorro D., Alarcón L., Ponce A., Tapia R., González-Aguilar H., Robles-Flores M., Mejía-Castillo T., Segovia J., Bandala Y., Juaristi E., González-Mariscal L.
Publicada:
15 sep 2009
Resumen:
Here, we have analyzed the subcellular destiny of newly synthesized tight junction protein zona occludens (ZO)-2. After transfection in sparse cells, 74% of cells exhibit ZO-2 at the nucleus, and after 18 h the value decreases to 17%. The mutation S369A located within the nuclear exportation signal 1 of ZO-2 impairs the nuclear export of the protein. Because Ser369 represents a putative protein kinase C (PKC) phosphorylation site, we tested the effect of PKC inhibition and stimulation on the nuclear export of ZO-2. Our results strongly suggest that the departure of ZO-2 from the nucleus is regulated by phosphorylation at Ser369 by novel PKC epsilon. To test the route taken by ZO-2 from synthesis to the plasma membrane, we devised a novel nuclear microinjection assay in which the nucleus served as a reservoir for anti-ZO-2 antibody. Through this assay, we demonstrate that a significant amount of newly synthesized ZO-2 goes into the nucleus and is later relocated to the plasma membrane.
Filiaciones:
Chamorro D.:
Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
Alarcón L.:
Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
Ponce A.:
Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
Tapia R.:
Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
González-Aguilar H.:
Univ Nacl Autonoma Mexico, Fac Med, Dept Biochem, Mexico City 04510, DF, Mexico
Robles-Flores M.:
Univ Nacl Autonoma Mexico, Fac Med, Dept Biochem, Mexico City 04510, DF, Mexico
Mejía-Castillo T.:
Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
Segovia J.:
Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
Bandala Y.:
Department of Chemistry, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
Juaristi E.:
Department of Chemistry, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
González-Mariscal L.:
Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico, D.F., 07360, Mexico
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