Purchase this article with an account.
IS Zagon, JW Sassani, TB Ruth, AE Leure-duPree, PJ McLaughlin; Nucleocytoplasmic Distribution Of Opioid Growth Factor (OGF) And OGF Receptor In Rat Cornea . Invest. Ophthalmol. Vis. Sci. 2002;43(13):1654.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
The native opioid growth factor (OGF), [Met5]-enkephalin, is a tonic inhibitory peptide that modulates cell proliferation and migration, as well as tissue organization, during development, homeostatic cellular renewal, and wound healing. OGF action is mediated by the OGF receptor (OGFr). Purpose: To determine the subcellular location(s) of OGFr and OGF in rat corneal epithelium. Method: Immunoelectron microscopic studies were performed using a postembedding procedure and immunogold labeling of epithelium from peripheral rat cornea. Following fixation and embedding in Unicryl, sections were stained with antibodies to OGFr and/or OGF; secondary antibodies were conjugated to 6 or 10 nm gold particles. Both single and double-face labeling studies were performed. Results: Immunogold labeling of OGFr was detected proximal to the outer nuclear envelope, in putative nuclear pores, within the inner nuclear matrix, in a paranuclear position, and at the periphery of heterochromatin. OGF was found in locations similar to OGFr, as well as in aggregates extending from the plasma membrane to the nuclear envelope. OGFr and OGF were localized in both the basal and suprabasal layers. Double labeling experiments revealed OGFr-OGF complexes that were colocalized on the outer nuclear envelope, in the paranuclear cytoplasm, extending across the nuclear envelope, and in the nucleus. Conclusion: These results are consistent with previous pharmacological, biochemical, and structural studies indicating a nuclear association of OGFr, and show that the receptor is located on the outer nuclear envelope. It appears that OGF is an autocrine produced peptide that is secreted into the extracellular milieu, and imported to the outer nuclear envelope where it interacts with the OGF receptor. The OGF-OGFr complex translocates across the nuclear pore where OGF-OGFr becomes associated at the heterochromatin-euchromatin margin, and thereby presumably participates in the governing of DNA synthesis.
This PDF is available to Subscribers Only