Inhibition of the binding of low-density lipoprotein to its cell surface receptor in human fibroblasts by positively charged proteins

M. S. Brown, T. F. Deuel, S. K. Basu, J. L. Goldstein

Research output: Chapter in Book/Report/Conference proceedingChapter

45 Scopus citations

Abstract

A group of proteins and polyamino acids with positively charged domains were shown to inhibit the binding of 125I-LDL to its receptor on the surface of human fibroblasts. The list of inhibitory proteins included platelet factor 4 (which has a cluster of lysine residues at its carboxyl terminus), two lysine-rich histones, poly-L-lysines of chain length greater than 4, and protamine. These proteins were effective in the concentration range of 5-50 μg/ml. Two other positively charged proteins, lysozyme and avidin, did not inhibit 125I-LDL binding. Kinetic studies suggested that protamine was not acting simply as a competitive inhibitor with regard to the LDL receptor. In light of previous data showing that polyanions such as heparin and polyphosphates also inhibit 125I-LDL binding to its cell surface receptor, the current findings suggest that charge interactions are important in this binding reaction. In a related series of studies, a number of glycoproteins and their asialo derivatives as well as a number of sugar phosphates failed to inhibit 125I-LDL binding to its receptor in fibroblasts.

Original languageEnglish (US)
Title of host publicationJournal of Supramolecular and Cellular Biochemistry
Pages223-234
Number of pages12
Volume8
Edition3
StatePublished - 1978

ASJC Scopus subject areas

  • Biochemistry

Fingerprint Dive into the research topics of 'Inhibition of the binding of low-density lipoprotein to its cell surface receptor in human fibroblasts by positively charged proteins'. Together they form a unique fingerprint.

  • Cite this

    Brown, M. S., Deuel, T. F., Basu, S. K., & Goldstein, J. L. (1978). Inhibition of the binding of low-density lipoprotein to its cell surface receptor in human fibroblasts by positively charged proteins. In Journal of Supramolecular and Cellular Biochemistry (3 ed., Vol. 8, pp. 223-234)