Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published April 1986 | Published
Journal Article Open

Assembly of Protein 4.1 during Chicken Erythroid Differentiation

Abstract

Protein 4.1 is a peripheral membrane protein that strengthens the actin-spectrin based membrane skeleton of the red blood cell and also serves to attach this structure to the plasma membrane. In avian erythrocytes it exists as a family of closely related polypeptides that are differentially expressed during erythropoiesis. We have analyzed the synthesis and assembly onto the membrane skeleton of protein 4.1 and in this paper we show that its assembly is extremely rapid and highly efficient since greater than 95% of the molecules synthesized are assembled in less than 1 min. The remaining minor fraction of unassembled protein 4.1 differs kinetically and is either degraded or assembled with slower kinetics. All protein 4.1 variants exhibit a similar kinetic behavior irrespective of the stage of erythroid differentiation. Thus, the amount and the variants ratio of protein 4.1 assembled are determined largely at the transcriptional or at the translational level and not posttranslationally. During erythroid terminal differentiation the molar amounts of protein 4.1 and spectrin assembled change. In postmitotic cells, as compared with proliferative cells, far more protein 4.1 than spectrin is assembled onto the membrane-skeleton. This modulation may permit the assembly of an initially flexible membrane skeleton in mitotic erythroid cells. As cells become postmitotic and undergo the final steps of maturation the membrane skeleton may be gradually stabilized by the assembly of protein 4.1.

Additional Information

© 1986 Rockefeller University Press. After the Initial Publication Period, RUP will grant to the public the non-exclusive right to copy, distribute, or display the Article under a Creative Commons Attribution-Noncommercial-Share Alike 4.0 International license, as described at https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode, or updates thereof. Received for publication 25 October 1985, and in revised form 25 November 1985. We thank Shelly Diamond (California Institute of Technology) for performing the centrifugal elutriation. We also thank Dr. John Ngai (California Institute of Technology) for his valuable comments on the manuscript. This work was supported by grants from the National Institutes of Health, National Science Foundation, and Muscular Dystrophy Association. M. Staufenbiel was also supported by Cancer Research Campaign International Fellowship awarded by the International Union Against Cancer and a Senior lnvestigatorship of the American Heart Association, Greater Los Angeles Affiliate.

Attached Files

Published - STAjcb86.pdf

Files

STAjcb86.pdf
Files (3.5 MB)
Name Size Download all
md5:71239812f67f2048e222053a4cf283f4
3.5 MB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 17, 2023