The Journal of Experimental Medicine
Fluorescence In Vivo Endomicroscopy
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
This Article
Right arrow Full Text (PDF, 1427K)
Right arrow Alert me when this article is cited
Right arrow Citation Map
Services
Right arrow Email this article
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new content in the JEM
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Woods, J. W.
Right arrow Articles by Singer, I. I.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Woods, J. W.
Right arrow Articles by Singer, I. I.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

Journal of Experimental Medicine, Vol 178, 1935-1946, Copyright © 1993 by Rockefeller University Press

ARTICLES

5-lipoxygenase and 5-lipoxygenase-activating protein are localized in the nuclear envelope of activated human leukocytes

JW Woods, JF Evans, D Ethier, S Scott, PJ Vickers, L Hearn, JA Heibein, S Charleson and II Singer
Department of Biochemical and Molecular Pathology, Merck Research Laboratories, Rahway, New Jersey 07065.

The intracellular distribution of the enzyme 5-lipoxygenase (5-LO) and 5-lipoxygenase-activating protein (FLAP) in resting and ionophore- activated human leukocytes has been determined using immuno- electronmicroscopic labeling of ultrathin frozen sections and subcellular fractionation techniques. 5-LO is a 78-kD protein that catalyzes the conversion of arachidonic acid to leukotrienes. FLAP is an 18-kD membrane bound protein that is essential for leukotriene synthesis in cells. In response to ionophore stimulation, 5-LO translocates from a soluble to a sedimentable fraction of cell homogenates. In activated leukocytes, both FLAP and 5-LO were localized in the lumen of the nuclear envelope. Neither protein could be detected in any other cell compartment or along the plasma membrane. In resting cells, the FLAP distribution was identical to that observed in activated cells. In addition, subcellular fractionation techniques showed > 83% of immunoblot-detectable FLAP protein and approximately 64% of the FLAP ligand binding activity was found in the nuclear membrane fraction. A fractionation control demonstrated that a plasma membrane marker, detected by a monoclonal antibody PMN13F6, was not detectable in the nuclear membrane fraction. In contrast to FLAP, 5-LO in resting cells could not be visualized along the nuclear envelope. Except for weak labeling of the euchromatin region of the nucleus, 5-LO could not be readily detected in any other cellular compartment. These results demonstrate that the nuclear envelope is the intracellular site at which 5-LO and FLAP act to metabolize arachidonic acid, and that ionophore activation of neutrophils and monocytes results in the translocation of 5-LO from a nonsedimentable location to the nuclear envelope.
Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:



  Home | Help | Feedback | Subscriptions | Archive | Search
TABLE OF CONTENTS