arrow
Return

Protein shape modulates crowding effects

delete2018-10-09
delete82
delete
OA
AI
A
Alex J. Guseman
G
Gerardo M. Perez Goncalves
S
Shannon L. Speer
G
Gregory B. Young
G
Gary J. Pielak *
DOI:10.1073/pnas.1810054115delete
deleteOriginal
deleteShare
deleteSave
View PDF
Abstract

Abstract

En 中文
Protein-protein interactions are usually studied in dilute buffered solutions with macromolecule concentrations of <10 g/L. In cells, however, the macromolecule concentration can exceed 300 g/L, resulting in nonspecific interactions between macromolecules. These interactions can be divided into hard-core steric repulsions and soft chemical interactions. Here, we test a hypothesis from scaled particle theory; the influence of hard-core repulsions on a protein dimer depends on its shape. We tested the idea using a side-by-side dumbbell-shaped dimer and a domain-swapped ellipsoidal dimer. Both dimers are variants of the B1 domain of protein G and differ by only three residues. The results from the relatively inert synthetic polymer crowding molecules, Ficoll and PEG, support the hypothesis, indicating that the domain-swapped dimer is stabilized by hard-core repulsions while the side-by-side dimer shows little to no stabilization. We also show that protein cosolutes, which interact primarily through nonspecific chemical interactions, have the same small effect on both dimers. Our results suggest that the shape of the protein dimer determines the influence of hard-core repulsions, providing cells with a mechanism for regulating protein-protein interactions.
Keywords:
macromolecular crowding
protein-protein interactions
scaled particle theory
AI Summary

AI Summary

Key information extracted from the uploaded paper, including a brief overview, abstract, background, key highlights, visual analysis, and future outlook.

Journal

P
Proceedings of the National Academy of Sciences of the United States of America
IF:
9.1
Papers:
10.8W
Citations:
73.5W

Organization

U
university of north carolina
Scholars:
7.4W
Papers: 6.5W
Citations: 93
U
University of North Carolina School of Medicine
Scholars:
1.6W
Papers: 1.1W
Citations: 20