JCB logo
Accuri Cytometers
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents
This Article
Right arrow Full Text (PDF, 2180K)
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 JCB
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 Meldolesi, J.
Right arrow Articles by Palade, G. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Meldolesi, J.
Right arrow Articles by Palade, G. E.
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?
The Journal of Cell Biology, Vol 49, 109-129, Copyright © 1971 by Rockefeller University Press

ARTICLE

COMPOSITION OF CELLULAR MEMBRANES IN THE PANCREAS OF THE GUINEA PIG : I. Isolation of Membrane Fractions



J. Meldolesi 1, J. D. Jamieson 1, and G. E. Palade 1

1 From The Rockefeller University, New York 10021.

Dr. Meldolesi's present address is the Università degli Studi, Instituto di Farmacologia e di Terapia, Milan, Italy

The subcellular components involved in the synthesis, transport, and discharge of secretory proteins in the guinea pig pancreatic exocrine cell have been isolated from gland homogenates by differential and gradient centrifugation. They include rough and smooth microsomes derived respectively from the rough endoplasmic reticulum and Golgi periphery, a zymogen granule fraction consisting mainly of mature zymogen granules and a smaller population of condensing vacuoles, and a plasmalemmal fraction. Membrane subfractions were obtained from the particulate components by treatment with mild (pH 7.8) alkaline buffers which extract the majority (>95%) of the content of secretory proteins, allowing the membranes to be recovered from the extracting fluid by centrifugation. The purity of the fractions was assessed by electron microscopy and by assaying marker enzymes for cross-contaminants. The rough and smooth microsomes were essentially free of mitochondrial contamination; the smooth microsomes contained <15% rough contaminants. The zymogen granule fraction and its derived membranes were free of rough microsomes and contained <3% contaminant mitochondria. The plasmalemmal fraction was heterogeneous as to origin (deriving from basal, lateral, and apical poles of the cell) and contained varying amounts of adherent fibrillar material arising from the basement membrane and terminal web. The lipid and enzymatic composition of the membrane fractions are described in the following reports.

Submitted on July 20, 1970
Revised on October 14, 1970


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